Autologous osteochondral grafting has demonstrated positive outcomes for treating articular cartilage defects by replacing the damaged region with a cylindrical graft consisting of bone with a layer of cartilage, taken from a non-loadbearing region of the knee. Despite positive clinical use, factors that cause graft subsidence or poor integration are relatively unknown. The aim of this study was to develop finite element (FE) models of osteochondral grafts within a tibiofemoral joint and to investigate parameters affecting osteochondral graft stability.

Initial experimental tests on cadaveric femurs were performed to calibrate the bone properties and graft-bone frictional forces for use in corresponding FE models, generated from µCT scan data. The effects of cartilage defects and osteochondral graft repair were measured by examining contact pressure changes using in vitro tests on a single cadaveric human tibiofemoral joint. Six defects were created in the femoral condyles which were subsequently treated with osteochondral autografts or metal pins. Matching µCT scan-based FE models were created, and the contact patches were compared. Sensitivity to graft bone properties was investigated.

The bone material properties and graft-bone frictional forces were successfully calibrated from the initial tests with good resulting levels of agreement (CCC=0.87). The tibiofemoral joint experiment provided a range of cases to model. These cases were well captured experimentally and represented accurately in the FE models. Graft properties relative to host bone had large effects on immediate graft stability despite limited changes to resultant cartilage contact pressure.

Model confidence was built through extensive validation and sensitivity testing, and demonstrated that specimen-specific properties were required to accurately represent graft behaviour. The results indicate that graft bone properties affect the immediate stability, which is important for the selection of allografts and design of future synthetic grafts.

The aim of this work was to develop a novel, accessible and low-cost method, which is sufficient to measure changes in meniscal position in a whole-knee joint model performing dynamic motion in a knee simulator.

An optical tracking method using motion markers, MATLAB (MATLAB, The MathWorks Inc.) and a miniature camera system (Raspberry Pi, UK) was developed. Method feasibility was assessed on porcine whole joint knee samples (n = 4) dissected and cemented to be used in the simulator (1). Markers were placed on three regions (medial, posterior, anterior) of the medial meniscus with corresponding reference markers on the tibial plateau, so the relative meniscal position could be calculated. The Leeds high kinematics gait profile scaled to the parameters of a pig (1, 2) was driven in displacement control at 0.5 Hz. Videos were recorded at cycle-3 and cycle-50. Conditions tested were the capsule retained (intact), capsule removed and a medial posterior root tear. Mean relative displacement values were taken at time-points relating to the peaks of the axial force and flexion-extension gait inputs, as well as the range between the maximum and minimum values. A one-way ANOVA followed by Tukey post hoc analysis were used to assess differences (p = 0.05).

The method was able to measure relative meniscal displacement for all three meniscal regions. The medial region showed the greatest difference between the conditions. A significant increase (p < 0.05) for the root tear condition was found at 0.28s and 0.90s (axial load peaks) during cycle-3. Mean relative displacement for the root tear condition decreased by 0.29 mm between cycle-3 and cycle-50 at the 0.28s time-point. No statistically significant differences were found when ranges were compared at cycle-3 and cycle-50.

The method was sensitive to measure a substantial difference in medial-lateral relative displacement between an intact and a torn state. Meniscus extrusion was detected for the root tear condition throughout test duration. Further work will progress onto human specimens and apply an intervention condition.

Cam-type femoroacetabular impingement is caused by bone excess on the femoral neck abutting the acetabular rim. This can cause cartilage and labral damage due to increased contact pressure as the cam moves into the acetabulum. However, the damage mechanism and the influence of individual mechanical factors (such as sliding distance) are poorly understood. The aim of this study was to identify the cam sliding distance during impingement for different activities in the hip joint.

Motion data for 12 different motion activities from 18 subjects, were applied to a hip shape model (selected as most likely to cause damage, anteriorly positioned with a maximum alpha angle of 80°). The model comprised of a pointwise representation of the acetabular rim and points on the femoral head and neck where the shape deviated from a sphere (software:Matlab).

The movement of each femoral point was tracked in 3D while an activity motion was applied, and impingement recorded when overlap between a cam point and the acetabular rim occurred. Sliding distance was recorded during impingement for each relevant femoral point.

Angular sliding distances varied for different activities. The highest mean (±SD) sliding distance was for leg-crossing (42.62±17.96mm) and lowest the trailing hip in golf swing (2.17±1.11mm). The high standard deviation in the leg crossing sliding distances, indicates subjects may perform this activity in a different manner.

This study quantified sliding distance during cam impingement for different activities. This is an important parameter for determining how much the hip moves during activities that may cause damage and will provide information for future experimental studies.

Variations in component positioning of total hip replacements can lead to edge loading of the liner, and potentially affect device longevity. These effects are evaluated using ISO 14242:4 edge loading test results in a dynamic system. Mediolateral translation of one of the components during testing is caused by a compressed spring, and therefore the kinematics will depend on the spring stiffness and damping coefficient, and the mass of the translating component and fixture. This study aims to describe the sensitivity of the liner plastic strain to these variables, to better understand how tests using different simulator designs might produce different amounts of liner rim deformation.

A dynamic explicit deformable finite element model with 36mm Pinnacle metal-on-polyethylene bearing geometry (DePuy Synthes, Leeds, UK) was used with material properties for conventional UHMWPE. Setup was 65° clinical inclination, 4mm mismatch, 70N swing phase load, and 100N/mm spring. Fixture mass was varied from 0.5-5kg, spring damping coefficient was varied from 0-2Ns/mm. They were changed independently, and in combination.

Maximum separation values were relatively insensitive to changes in the mass, damping coefficient, or both. The sensitivity of peak plastic strain, to this range of inputs, was similar to changing the swing phase load from 70N to approximately 150N – 200N. Increasing the fixture mass and/or damping coefficient increased the peak plastic strain, with values from 0.15-0.19.

Liner plastic deformation was sensitive to the spring damping and fixture mass, which may explain some of the differences in fatigue and deformation results in UHMWPE liners tested on different machines or with modified fixtures. These values should be described when reporting the results of ISO14242:4 testing.

Acknowledgements

Funded by EPSRC grant EP/N02480X/1; CAD supplied by DePuy Synthes.

The Exeter^™ V40 cemented polished tapered stem system has demonstrated excellent long-term outcomes. This paper presents a systematic review of the existing literature and reports on a large case series comparing implant fractures between the Exeter V40 series; 125 mm and conventional length stem systems.

A systematic literature search was performed adhering to PRISMA criteria. In parallel we performed a retrospective single centre study of Exeter^™ V40 femoral stem prosthetic fractures between April 2003– June 2020.

There are 25 reported cases of such prosthetic fractures confined to small case series and case reports within the literature. We report an additional 19 cases to the literature (mean age 66.3 ± 11.7 years; 12 female [63%]; body mass index 32.9 ± 5.9 kg/m²). The mean time from index procedure to fracture was 7.8 years (2.5–16.3, ±3.6). Exeter V40 stem fracture incidence was 0.27%. Incidence was significantly higher in 125 mm length stems compared to ≥150 mm length stems (1.26% vs 0.13%, respectively, p <0.001) and revision arthroplasty (1.209% vs 0.149%, p <0.001). When comparing different stem length cohorts, 125-mm short-stem were associated with stem body fractures (92% vs 29%, p = 0.0095), earlier time to fracture (6.2 vs 11.0 years, p = 0.0018), younger patient age at time of fracture (62.7 vs 72.6 years old, p = 0.037) and female sex (75% vs 43%, p = 0.33).

This case series in conjunction with the systematic review provides evidence stem morphology plays a role in femoral implant fracture. This complication remains rare, although we report a significantly higher incidence at up to 17 years follow-up than in the literature. As femoral geometries remain the same, increasing BMIs in THR patients should raise concern. Short 125 mm length Exeter V40 stems undoubtedly have a role in restoring anatomy and biomechanics in smaller femoral geometries, although the surgeon has to appreciate the higher risk of stem fracture and the associated predisposing factors which may necessitate meticulous surgical technique and planning.

Aims

The Exeter V40 cemented polished tapered stem system has demonstrated excellent long-term outcomes. This paper presents a systematic review of the existing literature and reports on a large case series comparing implant fractures between the Exeter V40 series; 125 mm and conventional length stem systems.

Abstract

Abstract

INTRODUCTION

There is great potential for the use of computational tools within the design and test cycle for joint replacement devices.

The increasing need for stratified treatments that are more relevant to specific patients, and implant testing under more realistic, less idealised, conditions, will progressively increase the pre-clinical experimental testing work load. If the outcomes of experimental tests can be predicted using low cost computational tools, then these tools can be embedded early in the design cycle, e.g. benchmarking various design concepts, optimising component geometrical features and virtually predicting factors affecting the implant performance. Rapid, predictive tools could also allow population-stratified scenario testing at an early design stage, resulting in devices which are better suited to a patient-specific approach to treatment.

The aim of the current study was to demonstrate the ability of a rapid computational analysis tool to predict the behaviour of a total hip replacement (THR) device, specifically the risk of edge loading due to separation under experimental conditions.

Introduction

One of the known mechanisms which could contribute to the failure of total hip replacements (THR) is edge contact. Failures associated with edge contact include rim damage and lysis due to altered loading and torques. Recent study on four THR patients showed that the inclusion of pelvic motions in a contact model increased the risk of edge contact in some patients. The aim of current study was to determine whether pelvic motions have the same effect on contact location for a larger patient cohort and determine the contribution of each of the pelvic rotations to this effect.

Acetabular tissue damage is implicated in osteoarthritis (OA) and investigation of in situ acetabular soft tissues behaviour will improve understanding of tissue properties and interconnections. The study aim was to visualise acetabular soft tissues under load and to quantify displacements using computed tomography (CT) scans (XtremeCT, Scano Medical).

A CT scan (resolution 82 μm) was performed on the disarticulated, unloaded porcine acetabulum. The femoral head was soaked in Sodium Iodide (NaI) solution and cling film wrapped to prevent transfer to the acetabular side. The joint was realigned, compressed using cable ties and re-scanned. The two images were down-sampled to 0.3 mm. Acetabular bone and soft tissues were segmented. Bony features were used to register the two background images, using Simpleware ScanIP 7.0 (Synopsys), to the same position and orientation (volume difference < 5%). Acetabular soft tissues displacements were measured by tracking the same points at the tissue edges on the two acetabular masks, along with difference in bone position as an additional error assessment.

The use of radiopaque solution provided a clear contrast allowing separation of the femoral and acetabular soft tissues in the loaded image. The image registration process resulted in a difference in bone position in the areas of interest equivalent to image resolution (0.3 mm, a mean of 3 repeats by same user). A labral tip displacement of 1.7 mm and a cartilage thickness change from 1.5 mm unloaded to 0.9 mm loaded, were recorded.

The combination of contrast enhancement, registration and focused local measurement was precise enough to reduce bone alignment error to that of image resolution and reveal local soft tissue displacements. These measurement methods can be used to develop models of soft tissues properties and behaviour, and therapy for hip tissue damage at early stage may be reviewed and optimised.

Introduction

Up to 60% of total hip arthroplasties (THA) in Asian populations arise from avascular necrosis (AVN), a bone disease that can lead to femoral head collapse. Current diagnostic methods to classify AVN have poor reproducibility and are not reliable in assessing the fracture risk. Femoral heads with an immediate fracture risk should be treated with a THA, conservative treatments are only successful in some cases and cause unnecessary patient suffering if used inappropriately. There is potential to improve the assessment of the fracture risk by using a combination of density-calibrated computed tomographic (QCT) imaging and engineering beam theory. The aim of this study was to validate the novel fracture prediction method against in-vitro compression tests on a series of six human femur specimens.

Introduction

Geometric variations of the hip joint can give rise to repeated abnormal contact between the femur and acetabular rim, resulting in cartilage and labrum damage. Population-based geometric parameterisation can facilitate the flexible and automated in silico generation of a range of clinically relevant hip geometries, allowing the position and size of cams to be defined precisely in three dimensions. This is advantageous compared to alpha angles, which are unreliable for stratifying populations by cam type. Alpha angles provide an indication of cam size in a single two-dimensional view, and high alpha angles have been observed in asymptomatic individuals.

Parametric geometries can be developed into finite element models to assess the potential effects of morphological variations in bone on soft tissue strains. The aim of this study was to demonstrate the capabilities of our parameterisation research tool by assessing impingement severity resulting from a range of parametrically varied femoral and acetabular geometries.

Aims

To investigate whether the duration of pain has an influence on the clinical outcomes of patients with low back pain (LBP) managed through the North East of England Regional Back Pain and Radicular Pain Pathway (NERBPP).

Background

Conservative treatment of acute AT ruptures with functional rehabilitation has demonstrated superior results with equal reported re-rupture rates but without the added complications of surgical treatment.

There is no consensus on the duration and method of treatment using functional rehabilitation regimes.

The purpose of this paper is to define our treatment regime, the Leicester Achilles Management Protocol (LAMP), supported with patient reported outcomes and objective measures of assessment.

Introduction

The stability of the elbow joint following an acute elbow dislocation is dependent on associated injuries. The ability to identify these concomitant injuries correctly directs management and improves the chances of a successful outcome. Interpretation of plain radiographs in the presence of either a dislocation or post-reduction films with plaster in-situ is difficult. This study aimed to assess the ability of orthopaedic registrars to accurately identify associated bony injuries on initial plain radiographs using CT as the gold standard for comparison.

INTRODUCTION

Mal-positioning of the acetabular component in total hip replacement (THR) could lead to edge loading, accelerated component wear, impingement and dislocation [1,2]. In order to achieve a successful position for the acetabular component, the assessment of the acetabular orientation with reference to different coordinate systems is important [3]. The aims of the present study were to establish a pelvic coordinate system and a global body coordinate system, and to assess the acetabular orientations of natural hips with reference to the two coordinate systems.

Introduction

The performance of total hip replacement (THR) devices can be affected by the quality of the tissues surrounding the joint or the mismatch of the component centres during hip replacement surgery. Experimental studies have shown that these factors can cause the separation of the two components during walking cycle (dynamic separation) and the contact of the femoral head with the rim of the acetabular liner (edge loading), which can lead to increased wear and shortened implant lifespan¹. There is a need for flexible pre-clinical testing tools which allow THR devices to be assessed under these adverse conditions. In this work, a novel dynamic finite element model was developed that is able to generate dynamic separation as it occurs during the gait cycle. In addition, the ability to interrogate contact mechanics and material strain under separation conditions provides a unique means of assessing the severity of edge loading. This study demonstrates these model capabilities for a range of simulated surgical translational mismatch values, for ceramic-on-polyethylene implants.

Aims

The importance of accurate identification and reporting of surgical site infection (SSI) is well recognised but poorly defined. Public Health England (PHE) mandated collection of orthopaedic SSI data in 2004. Data submission is required in one of four categories (hip prosthesis, knee prosthesis, repair of neck of femur, reduction of long bone fracture) for one quarter per year. Trusts are encouraged to carry out post-discharge surveillance but this is not mandatory. Recent papers in the orthopaedic literature have highlighted the importance of SSI surveillance and the heterogeneity of surveillance methods. However, details of current orthopaedic SSI surveillance practice has not been described or quantified.

Aims

We present a case series of five patients who had revision surgery following magnetic controlled growing rods (MGCR) for early onset scoliosis. Metallosis was found during revision in four out of five patients and we postulated a mechanism for rod failure based on retrieval analysis.

Acute Achilles tendon (AT) rupture management remains debatable but non-operative functional regimes are beginning to dominate current treatment algorithms. The aim of this study was to identify predictors of functional outcome in patients with AT ruptures treated non-operatively with an immediate weight bearing functional regime in an orthosis.

Analysis of prospectively gathered data from a local database of all patients treated non-operativelyat our institution with anAT rupture was performed. Inclusion criteria required a completed Achilles Tendon Rupture Score (ATRS) at a minimum of 8 months post rupture. The ATRS score was correlated against age, gender, time following rupture, duration of treatment in a functional orthoses (8- and 11-week regimes) and complications. 236 patients of average age 49.5 years were included.

The mean ATRS on completion of rehabilitation was 74 points. The mean ATRS was significantly lower in the 37 females as compared to the 199 males, 65.8 vs 75.6 (p = 0.013). Age inversely affected ATRS with a Pearsons correlation of −0.2. There was no significant difference in the ATRS score when comparing the two different treatment regime durations. There were 12 episodes of VTE and 4 episodes of re-rupture. The ATRS does not change significantly after 8 months of rupture.

Patients with AT ruptures treated non-operatively with a functional rehabilitation regime demonstrate good function with low re-rupture rates. Increasing age and female gender demonstrate inferior functional outcomes.

Introduction

The number of total hip replacements taking place across the UK continues to grow. In an ageing population, with people living longer and placing greater strain on their prostheses, the number of peri-prosthetic femoral fractures is increasing. We studied the economic impact this has on a large university teaching hospital.

The K2M MESA Rail is a new implant with a unique beam-like design which provides increased rigidity compared with a standard circular rod of equivalent diameter potentially allowing greater control and maintenance of correction. The aim of this study was to review our early experience of this implant.

We retrospectively reviewed the case notes and radiographs of all consecutive cases of spinal deformity correction in which at least one rail was used. All radiological measurements were made according to the Scoliosis Research Society definitions.

Since June 2012 thirty-three cases of spinal deformity correction were performed using the K2M Rail system. One case was excluded as there were no pre-operative radiographs. Median age was 15 years; there were 23 females. There were 26 scoliosis cases of which two had associated Chiari malformation, three were neuromuscular, and the remainder were adolescent idiopathic cases. Six patients had kyphotic deformity secondary to Scheuermann's disease. Mean length of follow-up was 16 months. In the scoliosis cases the mean pre-operative Cobb angle of the major curve was 58.6° with a mean correction of 35.6°. The mean post-operative thoracic kyphosis was 21.1°. The median number of levels included in the correction was 13. Bilateral rails were used in four cases, the remainder had one rail on the concave side and a contralateral rod. No patients required an anterior release or staged surgery. All kyphosis cases had posterior apical corrective osteotomies. The mean pre-operative thoracic kyphosis was 75.5° with a mean correction of 31°. The median number of levels included in the correction was 11. Four patients had bilateral rails. No patients required anterior release. Complications: two patients had prominent hardware. One patient had a malpositioned screw causing nerve root irritation, which was removed. There were three superficial infections, which settled with antibiotics. There were no cases of implant breakage, screw pull-out, or loss of correction.

The K2M MESA Rail is a powerful new implant design which helps to achieve and maintain satisfactory correction of complex spinal deformity, and is particularly strong at correcting kyphotic deformity. It also enables restoration of normal thoracic kyphosis, particularly in idiopathic thoracic curves, which tend to be lordosing. This may prevent thoracic flat back and potential long-term sequelae. Early results show that the system is as safe and effective as other posterior deformity correction implants on the market, however, it requires further prospective follow-up to ascertain its outcomes in the long-term.

Aim:

To determine the efficacy and safety of the Magec system in early onset scoliosis (EOS).

Aim:

To measure truncal parameters for patients treated with growing rod systems for early onset scoliosis (EOS).

Introduction and aims

Low back pain is a common complaint, affecting up to one third of the adult population costing over £1 billion to the NHS each year and £3.5 billion to the UK economy in lost production. The demand for spinal injections is increasing allowing for advanced spinal physiotherapists to perform the procedure. The objective of this study was to investigate outcome following spinal injections performed by consultant spinal surgeon (n=40) and advanced spinal physiotherapists (ASP) (n=40) at our centre.

Fractures of the femoral head are a challenging problem. The most often performed head preserving procedure worldwide is closed reduction and insertion of cannulated screws under fluoroscopic control. The use of navigation is still experimental in general trauma since rigid reference markers must be attached to all fragments. The examined system (Surgix®, Tel Aviv, Israel) is a fluoroscopy based image analysing system. It consists of a workstation and X-ray opaque markers in surgical tools. When the tool is visible in a C-arm shot a trajectory is displayed as additional layer in the image to serve as guidance for the surgeon.

Forty synthetic femurs (Synbone®, Malans, Switzerland) were used and placed inside foam to simulate the soft tissue of the thigh. The models were equipped with 4.5mm radio-opaque markers at the fovea capitis femoris as target point. The aim was to bring the tip of a K-wire as close as possible to the target point entering the bone at the lateral base of the greater trochanter in a center-center position. Twenty were done under image guidance and 20 were operated the conventional way. Outcome measures included the accuracy (the distance between the tip of the wire and the target in a CT), the number of guide wire insertions, procedure duration, radiation exposure and learning curve.

In the image guided group optimal guide wire placement was accomplished on first pass in 65% of the cases as compared to 5% in the conventional group (p = < 0.0001). The average number of trial and error was significantly lower in the guided group (1.7 vs. 5.8, p = < 0.0001). Consequently the average duration of the guided procedure was significantly shorter (p = 0.0008) along with radiation exposure time reduced by over 70% (p = 0.0002). The guidance system hit averaged 5.8 mm off target as compared to 5.3 mm for the freehand method (p = 0.3319).

Image based guidance significantly shortened the procedure, reduced the radiation exposure and the number of trials without changing the surgeons workflow and can be used in trauma cases were reference marker based navigation is not applicable.

Computer assisted surgery (CAS) is used in trauma surgery to reduce radiation and improve accuracy but it is time consuming. Some trials for navigation in small bone fractures were made, but they are still experimental. One major problem is the fixation of the dynamic reference base for navigation. We evaluated the benefit of a new image based guidance-system (Surgix®, Tel Aviv, Israel) for fracture treatment in scaphoid bones compared to the conventional method without navigation. The system consists of a workstation and surgical devices with embedded radio opaque markers. These markers as well as the object of interest must be on the same C-arm shot. If a tool is detected in an image by the attached workstation additional information such as trajectories are displayed in the original fluoroscopic image to serve the surgeon as aiming device. The system needs no referencing and no change of the workflow.

For this study 20 synthetic hand models (Synbone®, Malans, Switzerland) were randomised in two groups. Aim of this study was a central guide-wire placement in the scaphoid bone, which was blindly measured by using postoperative CT-scans. Significant distinctions related to the duration of surgery, emission of radiation, radiation dose, and trials of guide-wire positioning were observed.

By using the system the surgery duration was with 50 % shortened (p = 0.0054) compared to the conventional group. One reason might be the significant reduction of trials to achieve a central guide-wire placement in the bone (p = 0.0032). Consequently the radiation exposure for the surgeon and the patient could be shortened by reduction of radiation emission (p = 0.0014) and radiation dose (p = 0.0019).

By using the imaged based guidance system a reduction of surgery duration, radiation exposure for the patient and the surgeon can be achieved. By a reduced number of trials for achieving a central guide-wire position the risk of weakening the bone structure can be minimised as well by using the system. The system seems helpful where navigation is not applicable up to now. The surgical workflow does not have to be chanced.

Background

Replacing bone lost as a consequence of trauma or disease is a major challenge in the treatment of musculoskeletal disorders. Tissue engineering strategies seek to harness the potential of stem cells to regenerate lost or damaged tissue. Bone marrow aspirate (BMA) provides a promising autologous source of skeletal stem cells (SSCs) however, previous studies have demonstrated that the concentration of SSCs required for robust tissue regeneration is below levels present in iliac crest BMA, emphasising the need for cell enrichment strategies prior to clinical application.

Background

Skeletal stem cells (SSCs) have been used for the treatment of osteonecrosis of the femoral head to prevent subsequent collapse. In isolation SSCs do not provide structural support but an innovative case series in Southampton, UK, has used SSCs in combination with impaction bone grafting (IBG) to improve both the biological and mechanical environment and to regenerate new bone at the necrotic site.

Background

Skeletal stem cells can be combined with human allograft, and impacted to produce a mechanically stable living bone composite. This strategy has been used for the treatment of femoral head avascular necrosis, and has been translated to four patients, of which three remain asymptomatic at up to three year follow-up. In one patient collapse occurred in both hips due to widely distributed and advanced AVN disease, necessitating bilateral hip arthroplasty. However this has provided the opportunity to retrieve the femoral heads and analyse human tissue engineered bone.

Recent approaches have sought to harness the potential of stem cells to regenerate bone lost as a consequence of trauma or disease. Bone marrow aspirate (BMA) provides an autologous source of skeletal stem cells (SSCs) for such applications, however previous studies have demonstrated that the concentration of SSCs present in iliac crest BMA is below that required for robust bone regeneration. Here we present a novel acoustic-facilitated filtration strategy to concentrate BMA for SSCs, clinically applicable for intra-operative orthopaedic use.

The aim of this study was to demonstrate the efficacy of this strategy in concentrating SSCs from iliac crest bone marrow, as well as femoral canal BMA from older patients.

Iliac crest BMA (Lonza, Rockville, MD, USA) and femoral canal BMA was obtained with informed consent from older patients during total hip replacement. 5 to 40ml of BMA was processed via the acoustically-aided exclusion filtration process to obtain 2-8 fold volume reductions. SSC concentration and function was assessed by flow-cytometry, assays for fibroblastic colony-forming units (CFU-F) and multi-lineage differentiation along chondrogenic, osteogenic and adipogenic pathways examined. Seeding efficiency of enriched and unprocessed BMA (normalised to cell number) onto allograft was assessed.

Iliac crest BMA from 15 patients was enriched for SSCs in a processing time of only 15 minutes. Femoral BMA from 15 patients in the elderly cohort was concentrated up to 5-fold with a corresponding enrichment of viable and functional SSCs, confirmed by flow cytometry and assays for CFU-F. Enhanced osteogenic (P<0.05) and chondrogenic (P<0.001) differentiation was observed using concentrated aspirate, as evidenced by biochemical assay and semi-quantitative histological analysis. Furthermore, enhanced cell seeding efficiency onto allograft was seen as an effect of SSC concentration per ml of aspirate (P<0.001), confirming the utility of this approach for application to bone regeneration.

The ability to rapidly enrich BMA demonstrates potential for intra-operative application to enhance bone healing and offers immediate capacity for clinical application to treat many scenarios associated with local bone stock loss. Further in vivo analysis is ongoing prior to clinical tests.

Periprosthetic femoral fractures can occur as a complication of total hip arthroplasty and are often challenging to treat as the mechanical scenario is influenced by the presence of the metal prosthesis within the bone. This research focuses on finding the optimum fixation for transverse, Vancouver type B1 periprosthetic fractures, stabilised using locking plates and secured using screws. The aim of this study was to experimentally validate a computer model of a human femur, develop that model to represent a periprosthetic femoral fracture fixation and show how the model could be used to indicate differences between plating techniques.

In the first development stage, both a laboratory model and a finite element model were developed to evaluate the mechanical behaviour of an intact composite femur under axial loading. Axial strains were recorded along the medial length of the femur in both cases and compared to provide validation for the computational model predications. The computational intact femur model was then modified to include a cemented total hip replacement, and further adapted to include a periprosthetic fracture stabilised using a locking plate, with unicortical screws above, and bicortical screws below the transverse fracture.

For the intact femur case, the experimental and computational strain patterns correlated well with an average difference of 16%. Following the inclusion of the stem, there was a reduction in the strain in the region of the prosthesis reducing by an average of 45%. There was also a large increase in bulk stiffness with the introduction of the prosthesis. When the fracture and plate fixation were included, there was little difference in the proximal strain where the stem dominated, and the strains in the distal region were found to be highly sensitive to the distribution of the screws.

The results of this study indicate that screw configuration is an important factor in periprosthetic fracture fixation. A laboratory model of the periprosthetic facture case is now under development to further validate the computational models and the two approaches will then be used to determine optimum fixation methods for a range of clinical scenarios.

Purpose

Retrospective review of growth sparing spinal instrumentation.

Purpose

To evaluate efficacy of blood conservation strategies on transfusion requirements in adult scoliosis surgery and establish a protocol for cross matching.

AIM

Avascular necrosis (AVN) of the femoral head is a potentially debilitating disease of the hip in young adults. Impaction bone grafting (IBG) of morcellised fresh frozen allograft is used in a number of orthopaedic conditions. This study has examined the potential of skeletal stem cells (SSC) to augment the mechanical properties of impacted bone graft and we translate these findings into clinical practice.

Background, Context and Motivation

“Increases in reconstructive orthopaedic surgery, resulting from advances in surgical practice and the ageing population, have lead to a demand for bone graft that far exceeds supply.”…Traditional bone grafting methods have been linked with a number of negative issues including increased morbidity due to secondary operation site and action as a vector for spread of disease. (Hing 2004). A solution to these insufficiencies would be the creation of a synthetic osteoinductive bone graft material. This would vastly improve bone graft surgery success rates and expedite post-op recovery times. The aim of this study was to classify then explore the dissolution rates of three experimental hydroxyapatite/silicate apatite synthetic bonegrafts in physiological solutions, (phosphate buffered saline, (PBS) +/− serum proteins, (PBS +FCS). The overall objective being to identify whether there is an explainable significant difference in ion exchange that could be behind the osteoinductive phenomena.

Spinal cord injury following trauma is initially dealt with by acute hospitals. The early management including stabilization is usually performed by these centres. This is followed by onward referral to one of the Regional Spinal Injury Units.

There is concern of both sides of the fence regarding mobilization following spinal cord injury. The acute hospitals want to avoid the problems of prolonged recumbency and the Regional Spinal Injury Units wish to avoid the problems of early aggressive mobilization.

Therefore, we set out to discover if there was a standard approach to mobilising these patients following surgical stabilization, because of the oversubscribed resources of the spinal injury units and the wish to start mobilizing the injured as soon as possible.

A comparative audit of the Regional Spinal Injury Units in the UK and North American Units.

Regional Spinal Injury Units in United Kingdom and North America

Clear Management Plan

Mobilisation Schedule

We had replies from all Regional Spinal Injury Units in the UK and from seven in North America.

The Regional Spinal Injury Units all had differing approaches. Only a few were able to convey a clear management plan and mobilization schedule. Whereas the North American Units provided a ‘mobilize as able’ plan in all cases.

The North American Units had a ‘mobilize as able’ policy, whereas the UK units had a mixed approach. A coherent collaboration between the spinal surgeons stabilizing these injuries and the spinal injury units providing rehabilitation would improve patient management.

To assess adverse events related to XLIF approach in lumbar degenerative disease.

Recently novel minimally disruptive spine procedure eXtreme lateral Interbody Fusion i.e XLIF has been developed. It is 90 (off the midline true lateral approach, which allows large graft placement, excellent disc height restoration and indirect decompression at the stenotic motion segment. We describe our experience in 28 patients.

Retrospective review of records of patients undergoing surgery between July 2008- Jan 2010. Presenting complaints, number of levels performed and complications (medical, approach, or implant related) were audited.

Results: 28 patients (17 female: 11 male) with median age of 47 yrs, range (38-75) formed the study group. Average stay was 4 days. All patients had MRI of lumbar spine. 2/3 rd patients had low back pain as their presenting complaint. All patients had nerve monitoring through out the procedure. There were 12 single, 15 two level and 1 three level cases (total 45 levels). 14/28 patients underwent plating at the same time. EBL was 100ml. There were 11/45 adverse events (24.4%). 6 events were approach, 4 were implant bone interface and 1 medical related. Major complication occurred in 1 patient (3.6%).

2/3 rd of patients, were better after the surgery. Almost negligible blood loss, low infection rate and short average stay seemed to work in favour of this approach. Complications are there as (with any new procedure) our results indicate, but these are manageable and less common with this technique.

This did not require Ethics approval and there was no grant or industry support for the above.

Aims

To assess the accuracy of posterior and anterolateral methods of injection into the subacromial space (SAS) of the shoulder.

We aimed (1) to determine the factors which influence outcome after surgery for CES and (2) to study CES MRI measurements. 56 patients with evidence of a sphincteric disturbance who underwent urgent surgery (1994-2002) were identified and invited to clinic. 31 MRIs were available for analysis and randomised with 19 MRIs of patients undergoing discectomy for persistent radiculopathy. Observers estimated the percentage of spinal canal compromise and indicated whether they thought the scan findings could produce CES and whether the discs looked degenerate. Measurements were repeated after two weeks.

(1) 42 patients attended (mean follow up 60 months; range 25–114). Mean age at onset was 41 years (range 24–67). 26 patients were operated on within 48 hours of onset. Acute onset of sphincteric symptoms and the time to operation did not influence the outcomes. Leg weakness at onset persisted in a significant number at follow-up (p<0.005). Bowel disturbance at presentation was associated with sexual problems (<0.005) at follow-up. Urinary disturbance at presentation did not affect the outcomes. The 13 patients who failed their post-operative trial without catheter had worse outcomes. The SF36 scores at follow-up were reduced compared to age-matched norms in the population. The mean ODI was 29, LBOS 42 and VAS 4.5.

(2) No significant correlations were found between MRI canal compromise and clinical outcome. There was moderate to substantial agreement for intra- and inter-observer reproducibility.

Background

In suspected scaphoid fracture the initial scaphoid series plain radiographs are 84-94% sensitive for scaphoid fractures. Patients are immobilised awaiting diagnosis. Unnecessary lengthy immobilisation leads to lost productivity and may leave the wrist stiff. Early accurate diagnosis would improve patient management. Although Magnetic Resonance Imaging (MRI) has come to be regarded as the gold standard in identifying occult scaphoid injury, recent evidence suggests Computer Tomography (CT) to be more accurate in identifying scaphoid cortical fracture. Additionally CT and USS are frequently a more available resource than MRI.

We hypothesised that 16 slice CT is superior to high spatial resolution Ultrasonography (USS) in the diagnosis of radiograph negative suspected cortical scaphoid fracture and that a 5 point clinical examination will help to identify patients most likely to have sustained a fracture within this group.

Excessive implant migration and micromotion have been related to eventual implant loosening. The aim of this project is to develop a computational tool that will be able to predict the mechanical performance of a cementless implant in the presence of uncertainty, for example through variations in implant alignment or bone quality. To achieve this aim, a computational model has to be developed and implemented. However, to gain confidence in the model, it should be verified experimentally. To this end, the present work investigated the behavior of a cementless implant experimentally, and compared the results with a computational model of the same test setup.

A synthetic bone (item 3406, Sawbones Europe AB, Sweden) was surgically implanted with a Furlong cementless stem (JRI, Sheffield, UK) in a neutral position and subjected to a compression fatigue test of −200 N to −1.6 kN at a frequency of 0.5 Hz for 50000 cycles. Measurements of the micromotion and migration were carried out using two linear variable differential transducers and the strain on the cortex of the femur was measured by a digital image correlation system (Limess Messtechnik & Software Gmbh).

A three-dimensional model was generated from computed tomography scans of the implanted Sawbone and converted to a finite element (FE) model using Simple-ware software (Simpleware Ltd, Exeter, UK). Face-to-face elements were used to generate a contact pair between the Sawbone and the implant. A contact stiffness of 6000 N/m and a friction coefficient of 0.3 were assigned. The analysis simulated a load of −1.6 kN applied to the head of the implant shortly post implantation. The motions and strains recorded in the experiment were compared with the predictions from the computational model. The micromotion (the vertical movement of the implant during a single load cycle), was measured at the proximal shoulder, at the distal tip of the implant and at the bone-implant interface. The maximum value calculated proximally using FE was 61.3 μm compared to the experimental value of 59.6 μm. At the distal end, the maximum micromotion from FE was 168.9 μm compared to 170 μm experimentally. As a point of reference, some authors have suggested that in vivo, fibrous tissue formation may take place at the bone-implant interface when the micromotion is above 150 μm. The maximum micromotion found computationally at this interface was 99 μm which is below the threshold value defined. The longitudinal strain over the surface of the bone was variable and reached values of up to 0.15% computationally and 0.4% experimentally; this may be related to the coordinate systems used. However, it was noted that digital image correlation identified qualitatively similar strain patterns, and has great potential for measuring low level surface strains on bone.

In conclusion, the good correlation between the computational modelling and experimental tests provides confidence in the model for further investigations using probabilistic analyses where more complex configurations (for example change in implant alignment) can be analyzed.

Introduction: One of the main factors in the success of impaction bone grafting (IBG) in revision hip surgery is its ability to resist shear and to form a stable construct. Bone marrow contains multipotent skeletal stem cells and we propose that in combination with allograft will produce a living composite with biological and mechanical potential. In this study we looked at whether coating of the allograft with type 1 collagen followed by seeding with human bone marrow stromal cells (hBMSC) would enhance the grafts mechanical and biological properties.

Methods: A control group of plain allograft and three experimental groups where used to determine the effects that collagen and hBMSC have on IBG. The samples where impacted in standardised fashion previously validated to replicate femoral IBG, and cultured in vitro for 2 weeks. The samples then underwent mechanical shear testing and biochemical analysis for DNA content and Osteogenic activity.

Results: Collagen coating of the allograft prior to seeding with hBMSC significantly enhanced the mechanical properties of the construct compared to the ‘gold standard’ of plain allograft with a 22% increase in shear strength (p=0.002). The collagen coated group also showed increased osteogenic differentiation of the stromal cells (Alkaline Phospatase specific activity: 124 +/− 18.6 vs 54.6 +/− 9.6 nM pNPP/Hr/ngDNA p= < 0.01).

Discussion: This study has shown a role in the improvement of the biomechanical properties of IBG by coating with collagen and seeding with hBMSC. Collagen coating of IBG is a simple process and translation of the technique into the theatre setting feasible. The improvement in shear strength and cohesion could lead to earlier weight bearing for the patients and allow quicker recovery. The therapeutic implications of such composites auger well for orthopaedic applications. We are currently strengthening the above findings with an in vivo study.

Purpose: Females are at greater risk for anterior cruciate ligament (ACL) injury than males. Soccer may be a significant risk factor for ACL injury in adolescent females. ACL injury has significant consequences, including early onset of osteoarthritis. The purpose of the study was to determine

the number of ACL reconstruction surgeries performed on females between the ages of 13–18 inclusive in the Capital Health (CH) region from December 2000 to November 2005, and

Secondly, we describe factors relating to the mechanism of injury.

Method: Utilizing regional administrative data, we performed a standardized chart review and telephone interviews with female adolescents who underwent ACL reconstruction in the aforementioned time period. Information gathered included:

Age at reconstruction procedure.

The Alberta Soccer Association provided the number of registrants in indoor and outdoor seasons over the same time period.

Results: 2,824 ACL reconstruction operations were performed between December 2000 and November 2005. Reconstructions in females took place at an earlier age than in males. There were 266 ACL reconstructions in 256 adolescent females, of which 253 charts were available for review. One hundred and eleven (44%) knees were injured during soccer play. Seven patients with eight ACL reconstructions who injured their ACL playing soccer could not be located. ACL injuries occurred during indoor soccer in 52 (51%) cases despite higher registration in outdoor soccer during the same time-frame. 77 (74%) subjects played competitively and 81 (79%) subjects played two or more times/week.

Conclusion: Approximately 10% of ACL reconstructions were performed on adolescent females. Nearly 50% of ACL injuries occurred during soccer play, with a similar number seen in indoor versus outdoor play. Study limitations include the use of administrative data to assess the number of ACL reconstructions rather than ACL injuries. An awareness of the propensity of knee injuries in female soccer players is important. With the increased participation of young females in soccer and the serious lifelong implications of ACL rupture, prevention and training should be improved to lower the incidence of injury.

We aimed to evaluate the effects of implementing blood conservation strategies on transfusion requirements in adult patients undergoing scoliosis correction surgery. We retrospectively studied 50 consecutive adult patients who underwent scoliosis correction surgery (anterior, posterior or combined) between 2003 and 2007. All patients had a standard transfusion protocol. Age, BMI, pre and post operative haemoglobin, levels fused, duration of surgery, hospital stay, anti-fibrinolytics used and blood transfused was noted.

50 patients with mean age 24.6 years and mean BMI 21.9 kg/m2 were studied. 14 patients had anterior surgery, 19 patients had posterior surgery and 17 had combined anterior and posterior procedures. Mean number of levels fused was 9.5 (6–15) and mean duration of surgery was 284.6 minutes (135–550 minutes). Antifibrinolytics were used in 31 patients (62%), Aprotinin in 21(42%) and Tranexamic acid in 10 (20%). Mean blood loss in patients who received anti fibrinolytics was 530mls while mean blood loss in the other patients was 672mls. (p< 0.05). Blood transfusion was not required in any of the patients undergoing anterior correction only while 7 patients (41%) undergoing anterior and posterior correction and 3 patients (15.8%) undergoing posterior correction only required blood transfusion. Mean volume of cell saved blood re-transfused was 693.8 mls and mean hospital stay was 9.2 days. Mean pre-op haemoglobin was 13.2 g/dl (10.4–17.4) and mean post-op haemoglobin was 10.7 g/dl (7.7–15). 4 patients (8%) required intra and post-operative blood transfusion while 6 patients (12%) required blood transfusion postoperatively.

In conclusion, the use of anti-fibrinolytics like Aprotinin and Tranexamic acid reduces blood loss in scoliosis surgery. In the current scenario, with Aprotinin no longer available for use, our study would recommend the use of Tranexamic acid alongwith other blood conservation measures. In our unit we do not have blood cross matched for anterior surgery alone.

Introduction: Revision hip surgery is predicted to rise significantly over the coming decades. There is therefore likely to be an increasing need to overcome the large bone loss and cavitatory defects encountered in failed primary hip replacements. Impaction bone grafting (IBG) is a recognised technique for replacing lost bone stock. Achieving optimal graft impaction is a difficult surgical skill with a significant learning curve, balancing the need to achieve sufficient compaction to provide primary stability versus the need to keep impaction forces to a minimum to prevent iatrogenic fracture. In this study we have developed a revision acetabular model to test the hypothesis that the use of vibration and drainage with a new custom made perforated tamp could reduce the peak stresses imparted to the acetabulum during the impaction process and also improve the reliability and reproducibility of the impaction technique

Methods: Composite Sawbone hemi Pelvis models were used, with identical contained cavitatory defects created (Paprosky Type 2a). A strain gauge was attached to the medial wall of each hemi pelvis. A custom set of IBG tamps were made, and coupled a pneumatic hammer used to generate the vibrations. A standard impaction technique was used for the control group and the new vibration impaction for the experimental group. The cavity was progressively filled with morsellised allograft in 6 set steps for both groups with strain gauge readings taken during all impaction to monitor peak stresses. A standard Exeter Contemporary cup was then cemented into the graft bed for both groups. The models were mechanically loaded according to the protocol developed by Westphal et al at the angle of the joint reaction force during heel strike for a total of 50 000 cycles. 3D assessment of any micro motion post mechanical testing and degree of graft compaction was done with high resolution micro CT.

Results: Vibration impaction lead to a significant reduction in the peak stresses during the impaction process throughout the 6 steps (e.g. Step 1: 34.6 vs 110.8 MPa p=0.03). There was also far less variability in the peak stresses in the vibration group compared to standard impaction both in sequential impactions by the same surgeon and between different surgeons. One medial wall fracture occurred in the control group only. There was no difference in the degree of graft compaction or in the subsidence of the implant post cyclical loading.

Conclusion: Impaction bone grafting can be a difficult surgical skill with a significant learning curve. We believe that this new technique of applying vibration coupled with drainage to the IBG process in the acetabulum can reduce the risk of intraoperative fracture whilst achieving good graft compaction and implant stability. This technique therefore has the potential to widen the ‘safety margins’ of IBG and reduce the learning curve allowing more widespread adoption of the technique for replacing lost bone stock.

Introduction: Impaction bone grafting (IBG) using fresh frozen morsellised allograft is considered by many as the method of choice for replacing lost bone stock encountered during revision hip surgery. Bone marrow contains multipotent skeletal stem cells which have the potential to differentiate down a number of different cell lineages including osteoblasts, chondrocytes and adipocytes. In IBG it is desirable for as many as possible to go on to form bone rather than fibrous tissue to form a solid osseous construct. Whilst it is possible to push cells down the osteogenic lineage in vitro, some of these methods (e.g. the addition of Dexamethasone) are not translatable to clinical practice due to undesirable side effects. In this study we test the hypothesis that by coating the allograft with type 1 Collagen prior to seeding with human bone marrow stromal cells (hBMSC), the cellular adhesion and proliferation down an osteogenic lineage can be increased, leading to improved mechanical and biological properties of the IBG composite.

Methods: A control group of plain allograft and three experimental groups where used to determine the effects that collagen and hBMSC have on IBG (both individually and in combination). The samples where impacted in standardised fashion previously validated to replicate Femoral IBG, and cultured in vitro for 2 weeks. The samples then underwent mechanical shear testing giving a family of stress strain curves for each group, from which a Mohr coulomb failure curve can be plotted. Using the Mohr Coulomb failure equation τ = σ tanΦ + c, the shear strength (τ), Internal friction angle (tanΦ) and inter particulate cohesion (c) can then be calculated. Biochemical analysis was also performed for DNA content and Osteogenic activity.

Results: Mechanical shear testing demonstrated a significant improvement (p=0.002) in the grafts ability to resist shear with the coating of Collagen and seeding with hBMSC (245 vs 299 kPa) as well as improved cohesion between the bone graft particles (46 vs 144 kPa). Regression analysis of the shear strength showed a linear increase with compressive stress (R2 > 0.98) for all groups, indicating that the grafts satisfied the Mohr Coulomb failure law. In the two groups seeded with cells, the collagen coated group also showed increased osteogenic cell activity compared to the plain allograft.

Conclusion: This study has shown a role in the improvement of the mechanical and biological properties of IBG coated with type 1 Collagen and seeded with hBMSC. Collagen coating of IBG is a facile process and translation of the technique into the theatre setting feasible. The improvement in shear strength and cohesion could lead to earlier weight bearing for the patients and allow quicker recovery. The therapeutic implications of such composites auger well for orthopaedic applications. We are currently strengthening the above findings with an in vivo study.

Background: The simultaneous occurrence of spina bifida occulta (SBO) and spondylolysis has been noted previously. The occurrence of SBO and spondylolysis are approximately 17% and 5% respectively.

Aims: The aim of this study was to determine the incidence of SBO when a symptomatic spondylolysis has been proven.

Method: Analysis of four years of lumbar spine CT scans was performed. Patients with spondylolysis or spondylolisthesis caused by a pars defect were identified. These patients’ CT images were then reviewed to establish the patients who also had SBO.

Results: In this unit 650 CT scans of lumbar spines were performed in the last five years. Of these scans 100 (15%) were found to have a pars defect. The average age was 34.6. On CT 30 (30%) patients were shown to have SBO. Of the total 23 were under 18 years old and 13 (56%) of these patients had SBO associated with the spondylolysis. In the over 18 year olds 21 (27%) patients had SBO associated with spondylolysis.

On review of the 550 other scans the average age was 51.9 years old. The incidence of SBO within this group is 10%. Only 6% of these patients were under 18. Out of these 33 patients 30.3% (10 patients) had SBO. Over 18 the incidence of SBO was only 8.5%.

Conclusions: Our results indicate that the occurrence of SBO within the group with a spondylolysis is much higher than in the group where no spondylolysis is present. There is higher incidence of SBO in the younger patients with spondylolysis. 56% of paediatric patients with symptomatic spondylolysis will have SBO. Clinicians should be aware of this fact preoperatively to decide on the technique of repair of the symptomatic lysis.

Introduction: Impaction bone grafting (IBG) for revision hip surgery can be a difficult surgical skill with a fine line between construct failure from insufficient compaction and intraoperative fracture from high impaction forces. Following on from our experience in the femur, in this study we used an acetabular model to test the hypothesis that the use of vibration for IBG could reduce the peak stresses thus reducing the intraoperative fracture risk and also improve the reliability and reproducibility of the impaction technique.

Methods: Revision hemi pelvis models were made (Pra-prosky Type 2a). A standard impaction technique was used for the control group, and the impactor tamps were coupled with a pneumatic hammer for the vibration group. The cavity was filled in 6 set steps with strain gauge readings taken throughout. The pelvis construct was then mechanically loaded. Graft compaction and micro motion post mechanical testing was assessed with micro CT.

Results: Vibration impaction led to a significant reduction (p=0.03) in the peak stresses during the impaction process. There was also significantly less variability in peak stresses for the vibration group compared to standard, both in sequential impactions by the same surgeon and between different surgeons. One medial wall fracture occurred in the control group only, similar to fractures encountered in the clinical situation. There was no significant difference in the degree of graft compaction or in the subsidence of the cup.

Discussion: We believe that this new technique of applying vibration to the IBG process can reduce the risk of intraoperative fracture whilst achieving good graft compaction and implant stability. This technique therefore has the potential to widen the ‘safety margins’ of IBG and reduce the learning curve allowing more widespread adoption of the technique for replacing lost bone stock.

Background: Satisfaction following anterior and/or posterior spinal fusion varies greatly between individuals. The aim of this study was to assess patient satisfaction with the post-operative scars following surgical correction of scoliosis.

Methods: Prospective study; 31 patients (range 10–37 years), minimum of 2 months post-operation, interviewed in clinic or over the telephone using a questionnaire.

Results: Overall, 18 (58%) patients were disappointed with their scar; it was not what they expected, Patients with anterior scars or both anterior and posterior scars were the most disappointed groups.

39% of patients felt they were inadequately informed or not informed of the nature of scar. However, over 50% of those who had a specialist spinal nurse (SSN) consultation reported the scar to be as they expected. Scar length was the main source of disappointment. 55% reported their scars as being raised (keloid), particularly at the ends. Scar colour and shape was an issue for 23%, whilst 39% experienced prolonged healing. 19 patients had a pre-op consultation with the SSN, 11 did not get this opportunity, 1 declined.

Conclusion: Clearly there’s a need for improved education and understanding with regard to the nature of the scoliosis surgical scar(s). Input from a SSN is important and surgeons must clarify exactly what they mean when discussing operations with patients. This could be done with the aid of pictograms or leaflets detailing issues discussed in consultations along with the opportunity to meet patients who have already had surgery. These measures may lead to increased patient satisfaction with surgery.

Ethics approval: Audit

Interest Statement: None

Introduction: One of the main factors in the success of impaction bone grafting (IBG) in revision hip surgery is its ability to resist shear and to form a stable construct. Bone marrow contains multipotent skeletal stem cells and we propose that in combination with allograft will produce a living composite with biological and mechanical potential. In this study we looked at whether coating of the allograft with type 1 collagen followed by seeding with human bone marrow stromal cells (hBMSC) would enhance the grafts mechanical and biological properties.

Methods: A control group of plain allograft and three experimental groups where used to determine the effects that collagen and hBMSC have on IBG. The samples where impacted in standardised fashion previously validated to replicate femoral IBG, and cultured in vitro for 2 weeks. The samples then underwent mechanical shear testing and biochemical analysis for DNA content and Osteogenic activity.

Results: In isolation, both Collagen coating and seeding with hBMSC significantly enhanced the mechanical properties of the construct compared to the ‘gold standard’ of plain allograft. This was further enhanced (p=0.002) when the two processes are combined both with shear strength (245 vs. 299 kPa) and cohesion between the graft particles (46 vs. 144 kPa). The collagen coated group also showed increased osteogenic cell proliferation.

Discussion: This study has shown a role in the improvement of the mechanical properties of IBG coated with collagen and seeded with hBMSC. Collagen coating of IBG is a simple process and translation of the technique into the theatre setting feasible. The improvement in shear strength and cohesion could lead to earlier weight bearing for the patients and allow quicker recovery. The therapeutic implications of such composites auger well for orthopaedic applications. We are currently strengthening the above findings with an in vivo study.

Background: It remains unclear and controversial whether preoperative magnetic resonance imaging (MRI) in patients with adolescent idiopathic scoliosis (AIS) should be mandatory.

Aim: (1) To review our own practice, (2) conduct a national survey of United Kingdom Consultants, and (3) to perform a literature review.

Methods: Our own practice was established by identifying patients with AIS and examining whether an MRI scan was performed preoperatively. A survey of Consultants practice in the UK (British Scoliosis Members) was conducted by either an e-mail or telephone conversation. Finally, a literature survey was performed to establish current views.

Results: 118 patients with AIS were identified between 2003 and 2007. 78% of these patients underwent pre-operative MRI scans. Neural axis abnormalities were found in 8% of these patients. They included syrinx’s, chiari malformations, tonsillar herniation, cord tethering, central canal dilatation and undiagnosed spina bifida. Only 1 patient required intervention by the neurosurgeons. 92% of respondents to the national survey routinely performed preoperative MRI scans. The literature was not conclusive with regards to mandatory preoperative imaging.

Conclusion: Despite the literature showing little evidence, our survey shows a widespread consensus in clinical practice across the UK that routine preoperative MRI should be performed from a risk management viewpoint. It is mandatory in our unit to perform pre-operative MRI scans on all patients with AIS and would recommend that this becomes standard practice in all other units.

Ethics Approval: None/Audit

Interest Statement: None

In a high-risk technically advanced speciality like spine surgery, detailed information about all aspects of possible complications could be frightening for the patients, and thereby increase anxiety and distress. Therefore, aim of this study was to

Analyze written evidence of the consenting procedure pertaining to (a) nature of operation (b) benefits intended as a result of the operation (c) risks specific to the particular type of operation (c) general risks of spine surgery and anaestheia.

Methods: 70 adult elective, consecutive patients who had been listed for Lumbar discectomy /decompression surgery were chosen. The patients were presented with questionnaire of broad-based and open-ended questions designed to elicit theirs views in each of the following areas: expectation, knowledge of risks and alternatives, and personal attitude to information and satisfaction.

The study had a non-randomized design and patients divided into TWO groups Group A and group B.

The patients in the group A received standard information and were consented in a routine way without being given written proforma with all complications. The patients in the group B were given the same information as patients in the control group, with written information about common and rare complications. Patients in both groups were assessed on an ‘impact of events scale’ and hospital anxiety and depression scale immediately before ad after the consent process and again after surgery when they were discharged from the hospital.

For comparison of the proportion of Yes and No answers in 2 groups, Fisher’s exact test was used, and for comparison of more than 2 groups, the Chi-square test was used. For graded answers and other ordinal scales, the Mann–Whitney U-test was used for comparison of 2 groups and the Kruskal–Wallis test for comparison of more than 2 groups. Spearman’s test was used when assessing the correlation between 2 variables measured on an ordinal scale.

Results: Many patients (71%) agreed that the consent form made clear what was going to happen to them, and 77%) reported that it made them aware of the risks of the operation they were to undergo. Over a third (36%) saw it as a safeguard against mixups in the operating theatre. Few patients’ decision to accept surgery appeared to depend on risk information; 8% of patients said that they might have changed their decision, had they been advised of the risks of permanent stroke and myocardial infarction. However, 92% were clear that their decision to accept treatment would not have altered. The women in the group B had symptoms of definite anxiety to a significantly higher degree than the men before the operation. Post-operatively, patients receiving extended information were significantly more satisfied with both the written and oral information about common and rare complications than patients in the control group There were no statistically significant differences between the groups for anxiety or depression, as measured by the HADS, either before or after the operation between Group A and B. Provision of extended information describing most of the possible complications did not have any negative effects on the patients. The patients receiving the extended information were more satisfied and experienced to a higher degree that they could discuss alternative treatment methods with the surgeon. Discussion: Provision of extended information describing most of the possible complications did not have any negative effects on the patients. “Ignorance is bliss” may prove to be an excellent preoperative strategy for patients when outcome is good but detrimental to long term adjustment where significant postoperative complications arise. This raises the possibility that a separate consent could be used where these risks are pre-printed and explained in vocabulary easily understood by patients. The added advantages of this form would be less confusion for the patient and there would be written evidence that patients had understood each of the major risks involved with the proposed procedure. This proposed consent form would also reduce the chance that important risks and complications are omitted when consent is being taken, as well as tackling the issue of variability of experience or lack of knowledge by the person obtaining consent.

Introduction: Scoliosis surgery involves major blood loss, at times exceeding estimated blood volume.

Aim: To evaluate the effects of implementing blood conservation strategies (including cell salvage, controlled hypotension and anti-fibrinolytic drugs) on transfusion requirements in adult patients undergoing scoliosis correction surgery. To establish a protocol for cross matching of blood.

Study Design: We retrospectively studied 50 consecutive adult patients who underwent scoliosis correction surgery (anterior, posterior or combined) between 2003 and 2007. All patients were anaesthetised by the same anaesthetist who implemented a standard transfusion protocol. Age, BMI, pre and post operative haemoglobin, levels fused, duration of surgery, hospital stay, antifibrinolytics used and blood transfused was noted.

Results: 50 patients with mean age 24.6 years and mean BMI 21.9 kg/m2 were studied. 14 patients had anterior surgery, 19 patients had posterior surgery and 17 had combined anterior and posterior procedures. Mean number of levels fused was 9.5 (6–15) and mean duration of surgery was 284.6 minutes (135–550 minutes). Anti-fibrinolytics were used in 31 patients (62%), Aprotinin in 21(42%) and Tranexamic acid in 10(20%). Mean blood loss in patients who received anti fibrinolytics was 530mls while mean blood loss in the other patients was 672mls. (p< 0.05). Blood transfusion was not required in any of the patients undergoing anterior correction only while 7 patients (41%) undergoing anterior and posterior correction and 3 patients (15.8%) undergoing posterior correction only required blood transfusion. Mean volume of cell saved blood re-transfused was 693.8 mls and mean hospital stay was 9.2 days. Mean pre-op haemoglobin was 13.2 g/dl (10.4–17.4) and mean post-op haemoglobin was 10.7 g/dl (7.7–15). 4 patients (8%) required intra and post-operative blood transfusion while 6 patients (12%) required blood transfusion postoperatively.

Conclusion: Use of anti-fibrinolytics like Aprotinin and Tranexamic acid reduces blood loss in scoliosis surgery. In the current scenario, with Aprotinin no longer available for use, our study would recommend the use of Tranexamic acid alongwith other blood conservation measures.

In our unit we do not have blood cross matched for anterior surgery alone.

Idiopathic anterior knee pain (AKP) is common in adolescents and young adults. Most believe that the origin of the problem lies in the patello-femoral joint. Hamstring tightness has also been attributed as an important cause.

The aim of our study was to compare biometric parameters in patients with idiopathic AKP and controls. We also wanted to assess whether there was a difference in the relative electromyographic (EMG) onset times of the medial and lateral hamstrings.

We prospectively recruited patients with idiopathic anterior knee pain in the age group 11 to 25. Patients, but not the control population, had AP, lateral and skyline radiographs taken to rule out other pathology.

We had 34 patients (60 knees) with a minimum one year follow up. There was no difference in the symptoms of patients who attended physiotherapy as compared to those who did not. Patients with knee pain had significantly more hip external rotation (63 deg) as compared to the control (47 deg) group (p=0.001). Patients also had significantly more hamstring tightness (p=0.04).

Surface EMG was recorded (17 patients and controls each) from the medial and lateral hamstrings during 3 repetitions of a maximal voluntary isometric contraction exercise with the knee at 45° of flexion. The lateral hamstrings contracted 48.7 m.sec earlier than the medial hamstrings in patients as compared to controls.

AKP is a multifactorial and self-limiting disorder. Earlier contraction of the lateral hamstrings may cause tibial external rotation and contribute to the symptoms. Our data suggests that physiotherapy did not significantly alter the course of the condition. We believe that increased hip external rotation may contribute to the symptoms by increasing medial facet stress.

Introduction: Sacroiliac joint (SIJ) is a diarthrodial joint and can often be a source of chronic low back pain complex. We present a percutaneous technique for SIJ fusion and the functional and radiological outcome following the arthrodesis.

Aims and Objectives: To evaluate the functional and radiological outcome following percutaneous technique for SIJ fusion with HMA (Hollow modular anchor-age) screws.

Materials and Methods: 15 consecutive patients operated for SIJ fusion between Sep 2004 and Aug 2007 were included in the study. The diagnosis was confirmed with MRI and diagnostic injections. Pre-operative and post-operative functional evaluation was performed using SF-36 questionnaire and Majeed’s scoring system. Postoperative radiological evaluation was performed using plain radiographs. The Hollow modular anchorage (HMA) screws (Aesculap Ltd, Tuttlingen) packed with bone substitute were implanted percutaneous under fluoroscopic guidance

Results: The study group included 11 females and 4 males with a mean age of 48.7 years. Mean follow-up was 14 months. Mean SF-36 scores improved from 37 to 80 for physical function and from 53 to 86 for general health. The differences were statistically significant (Wilcoxon signed rank test; p < 0.05). Majeed’s score improved from mean 37 preoperative to mean 79 postoperative. The difference was statistically significant (student t test, p< 0.05). 13 had good to excellent results. The remaining 2 patients had improvement in SF-36 from mean 29 to 48. Persisting pain was potentially due to coexisting lumbar pathology. Intra-operative blood was minimal and there were no post operative or radiological complications in any patient.

Conclusion: Percutaneous HMA screws are a satisfactory way to achieve sacro-iliac stabilisation.

Background: Radicular pain has been reported even in the absence of a compressive lesion. It has been postulated that annular tears provide a conduit for pro-inflammatory substances, which can leak around the nerve root causing radiculitis. A link between the side of back pain and the side of the annular tear has been reported.

Objective: To establish whether the side of the annular tear may influence the side of the leg in a non-compressive setting.

Methods and patients: We identified 121 patients from the patients referred to our unit with back and radicular leg pain. The mean age of the cohort was 50 yrs and 49% were male. All these patients were investigated with an MRI scan that demonstrated no compression of the nerve root. We used strict exclusion criteria to exclude the patients with any neural compression, previous lumbar operation, degenerative deformity or an associated pathology such as peripheral neuropathy.

Results: The annular pathology was described as annular tears (47 patients) and non compressive disc bulges (106 patients). The odds ratio for the concurrence of an annular tear causing ipsilateral leg pain is 1.05 and for a non-compressive disc bulge causing ipsilateral leg pain is 2.14

Conclusion: A non-compressive disc bulge is more likey to cause radicular symptoms than an annular tear. Though, both these annular lesions can cause ipsilateral nerve root symptoms.

Anterior Lumbar Interbody Cages are used to recreate the lumbar lordosis in scoliosis surgery as anterior instrumentation is usually kyphogenic. We report two cases in which an anterior release was performed and interbody cages were used.In both these patients the cage was displaced anteriorly by an incorrectly positioned pedicle screw during posterior instrumentaion. In one case the cage was retrieved and correctly repositioned from the back using a TLIF approach, in the other this was noticed only post-operatively and patient needed another anterior surgery. We recommend a lateral Image Intensifier screening for combined anterior and posterior cases in which anterior cages are used in addition to posterior pedicle screws to prevent this complication.

Objective: To do assess changes in patients’ symptoms and the operative plan.

Materials and methods: 147 patients on a spinal surgery waiting list were assessed at a mean wait of 15.8 ± 1.3 months. 89 (61%) were male and 58 (39%) were female at a mean age of 49.7 yrs (16–78). 123 patients had a degenerative condition (20 cervical; 03 lumbar); 20 patients were seen for scoliosis; 2 with a post-traumatic kyphosis and 1 each with ankylosing spondylitis and a psudarthrosis.

Outcomes assessed: Changes in patients symptoms; changes from the initial operative plan when listed; requirement for re-imaging due to the wait.

Results: 31 patients reported improved symptoms at the re-assessment, while 96 were worse off and 20 were unchanged. 137 had axial pain when listed which changed to 116 at review (p=0.0018). 130 had radicular pain when listed which improved to 80 on re-assessment (p< 0.0001). However 19 reported an increase in the axial and 17 in the radicular symptoms. 71 patients (48.3%) required to be re-imaged at the re-assessment due to changes in the clinical picture. 42 patients received the procedure as originally listed. 30 patients were taken off the list, 24 received a different operation, and 38 had an interim or a definitive needling procedure while 13 await a re-assessment.

Conclusions: On the basis of the observations on our cohort, 1 in 5 operations were cancelled; 65% had an increased severity of the symptoms and just 1 in 3 patients were operated as planned while 48% required re-imaging. A long wait inevitably leads to changed symptoms and a review of these patients is mandatory. The review and the re-imaging adds to the burden on the already over-loaded system.

Objective: To assess the temporal geometric sagittal profile changes on serial radiographs of fractures of the thoracic and thoraco-lumbar spine.

Materials and methods: We have included 103 patients with thoracic or lumbar fractures were treated at our unit between June 2003 and May 2006. The patients were suitable for non-operative treatment. The mean age of the cohort was 46.9±2.4 (16–90). The sex distribution was equal. 94 patients had a single level lesion. 19 fractures were in the thoracic spine; 64 in the thoraco-lumbar (T11-L1) and 29 between L2 and L5. The radiographs were scored using the AO classification by 2 senior orthopaedic trainees. The radiographs were analysed at the Spine Research Laboratory. The results were computed using Stat, a statistical software.

Results: The changes were assessed over a mean period of 5.6 mo (range 1–49 mo; 95% CI 4.1–7.1 mo). Weighted kappa score of 0.58 was computed for the primary fracture type and 0.22 for the fracture sub-types. The inter-observer rater agreement was similar to that reported in literature. 7 patients showed a significant collapse. We report the association between the fracture types and the extent of collapse. We have also assessed the association between the medium to long term symptoms, the fracture types and the extent of collapse at the fracture sites and the adjacent disc.

Conclusion: Some fracture sub-types are more likely to collapse and cause long term symptoms. Identifying these fractures at the outset would help clarify surgical indications.

Objective: To assess the correlation between the side of the annular pathology and the radicular symptoms, in the absence of a compressive root lesion.

Materials and Methods: 121 patients underwent MRI scan fro axial back and radicular symptoms. The mean age was 49.9 yrs (24–80). The sex distribution was equal. We excluded the patients that had a compressive lesion, previous operations, spinal deformity, spondylolyses, an underlying pathology (tumour, trauma or infection) or a peripheral neuropathy. Annular pathology was documented as annular tear or a non-compressive disc bulge with its location and side. We also recorded marrow endplate changes and facet arthrosis.

Results: Bilateral radicular symptoms were reported in 16 (13.2%): right side in 33 (27.3%) and left in 47 (38.8%) patients. Additionally, 82 patients (67.8%) had axial back pain. 33 patients (27.3%) were noted to have a right sided annular pathology (tear or bulge) and 72 (59.5%) had a left sided annular lesion. 21 patients (17.4%) had a central annular tear and 43 (35.5%) had a generalised disc bulge. 14 patients (11.6%) with right sided symptoms also had annular pathology, while 38 patients (31.4%) with left sided symptoms had a left sided annular lesion. There was no statistical correlation between the side of symptoms and the side of the lesion (r = −0.00066, p=0.994), any particular annular pathology (annular tear r=0.085, p=0.35; disc bulge r-0.083, p=0.36). There was no correlation between the axial back pain and the annular pathology (r=0.004; p=0.97) and facet joint or marrow end plate changes (r= −,29, p=0.76).

Conclusions: Although annular pathology can cause the radicular symptoms, our results suggest that they do not influence the side of the symptoms.

Introduction: Sacroiliac joint pathology can contribute to lowback pain and sciatica. Its frequency and significance is controversial.

Aims: The purpose of this study is to evaluate the incidence and clinical significance of positive SI joint pathology on MRI scans.

Methodology: 353 MRI reports and scans carried out over a one year period for backpain and sciatica were reviewed. Demographic data and clinical notes of patients who had positive SI joint pathology on MRI scans were analysed. Correlation between clinical suspicion of SI joint pathology and MRI findings was studied.

Results: 12 scans showed pathology in the SI joint, an overall incidence of 3.3%.8(66%) were males and 4(33%) females. Only 4(33%) of these patients had Plain Film abnormality. Average age of 41.2 years (33–54). One patient was known case of Ankylosing Spondylitis. Other positive pathology included oedema, sclerois and bridging osteophytes. Clinicians requested inclusion of SI joint in 43 patients. 8 of these were positive, an incidence of 18.6%. In 130 patients, the SI joints were imaged as routine. This yielded positive pathology in 4 patients (3%).

Conclusion: Our study concludes that 18.6% of patients who are suspected to have SI joint involvement clinically have positive pathology on MRI scans.

Routine inclusion of imaging of the SI joint as part of lumbosacral spine MRI for back pain and sciatica shows only 3% positive results.

SI joint should be imaged only if clinically suspected.

Aim: To assess if commonly used scoliosis instrumentation activates metal detectors at airport security gates.

Methods: 20 patientswho had travelled by air following scoliosis surgery were included. The type of instrumentation, number of journeys, body mass index and whether the alarm was triggered off by the airport security detector was recorded. We asked the patients opinion regarding provision of documentary evidence of surgery.

Results: 10 patients had posterior instrumentation, 5 patients -Paediatric ISOLA,4 patients had anterior instrumentation and one patient, anterior and posterior instrumentation. 12 patients (60%) had travelled more than four times by air following surgery corresponding to 48 passes through an airport archway detector.5 patients out of 20 had set off the alarm while passing through the metal detector everytime of which 4 had posterior instrumentation and 1 anterior instrumentation. None of the patients with ISOLA instrumentation set of the alarm. Two patients had set off the alarm every time they passed through the metal detector and both of them had posterior instrumentation. 14 patients(70%) suggested that we should provide documentary evidence of surgery to avoid delays in the airport security check. 25 % of patients set of the metal detector alarm following scoliosis instrumentation.

Conclusion: Patients with posterior instrumentation are more likely to set off the alarm compared to patients with ISOLA instrumentation. It is important to be aware that scoliosis instrumentation can activate airport archway detectors in our present security climate and to provide documentation to patients in order to avoid embarassment and delays.

Introduction: Scoliosis Nursing service was introduced at the Cardiff Spinal Unit in 2003 as part of a multi-disciplinary team to improve quality of care for the patients and their families.

Background: This nurse is a point of contact at pre-admission and discharge. She co-ordinates the peri operative care and liases with other team-members including physiotherapists, occupational therapists and dieticians. Information regarding type of surgery, pain management, wounds/dressings, investigations is offered.

Aims and Objectives: To assess patients’ and families perception and satisfaction with the various aspects of care provided by the Scoliosis Nurse.

Methods and Materials: From 2005 to 2006, 30 consecutive patients and families who had seen the Scoliosis Nurse filled a questionnaire. 25 questionnaires were completed. Response was collated by an independent observer.

Results: All (100%) respondents felt that the presence of a nurse in clinic was beneficial. (100%) reported that they had received adequate information and literature. 66% of the patients felt a pre admission ward visit would be beneficial. 63% felt that further information about discharge and aftercare would be helpful.

Conclusion: Thus the Scoliosis Nurse was perceived to be beneficial by the patients and the family. Based on the abovefeedback the patient Information booklet has been updated.

Paravertebral anaesthesia is a particularly effective, safe and reliable option in scoliosis patients undergoing anterior release in whom percutaneous epidural placement may be difficult to perform. A recent systematic review and meta-analysis of randomized trials has demonstrated that whilst paravertebral block and thoracic epidural insertion provide comparable pain relief after thoracic surgery, paravertebral block placement is associated with a better side effect profile, including a reduction in pulmonary complications, hypotension, nausea and vomiting and urinary retention. We describe a case of a 16 year old female patient who underwent staged correction of her thoracolumbar scoliosis. A paravertebral catheter was inserted under direct vision for continuous infusion post operative analgesia following the anterior release. 48 hours after surgery a swelling was noted in the groin, which was confirmed with ultrasonography as a fluid collection. The swelling resolved upon removing the paravertebral catheter. This suggests that it was caused by the local anaesthetic fluid tracking along the psoas muscle. Retroperitoneal infections, venous thrombosis, femoral hernia, femoral artery aneurysm and inguinal lymphadenopathy are other differentials. Ultrasonography was a fast and sensitive investigation to rule out these differentials and determined that fluid communicating with the abdominal cavity was the cause for this swelling. The infused local anaesthetic had tracked down into the femoral triangle and the swelling resolved upon cessation of the infusion.

Background: Thoraco-lumbar fractures without a neurological deficit are usually suitable for non-operative treatment. The main area of clinical interest is the deformity at the injured levels. The deformity may be evident at the time of presentation, though could be expected to progress in time.

Objective: Accurate assessment of the temporal behaviour in the geometry of the injured segments in non-operatively treated thoracolumbar fractures with normal neurology.

Materials: 102 patients with thoracolumbar fractures without a neurological deficit were treated non-operatively at our unit between June 2003 and May 2006. The mean age of our patient cohort was 46.9 yrs (16–90 yrs). Strict criteria were followed to determine suitability for non-operative treatment. Supine radiographs were performed at the initial assessment. Erect radiographs were performed when trunk control was achieved and at follow-up assessments thereafter.

Methods: Quality Motion Analysis (QMA) software (Medical Metrics Inc, Houston, Tx) was used to measure rotational and translation changes between the end plates using a validated protocol. The radiographs were standardised for magnification and superimposed from different time points. Transformation matrices were used to track the changes. The AO classification was used to classify the fractures by 2 independent observers.

Results: A median of 4 radiographs were analysed for each patient (range 2–9), at a mean follow-up of 5.6 mo (95% CI 4.1–7.1 mo). 92% of the cohort had sustained a 1 level injury. 76% of the injuries were between T12 and L2; 19% were in the thoracic spine. An inter-observer rating of 0.58 was obtained for the classification of the primary fracture type. The mean rotational change was −1.4855° ± 0.248° (95% CI: −0.994° to–1.976°). The mean anterior vertebral body height collapse was −4.3444° ± 0.6938 (95% CI: −2.695 to −5.724). The mean posterior vertebral height collapse was −0.7987 ± 0.259 (95% CI: −0.284 to −1.313).

Conclusions: We report the use of QMA software to track changes in the vertebral body geometry accurately. This has implications on the clinical aspects of management of thoracolumbar fractures based to progression of deformity that could be explored in future studies.

Background data: Previous studies have questioned the quality of information available on the internet. Internet research has proven to more prevalent among scoliosis patients as compared to other orthopaedic conditions.

Aim: Scoliosis websites identified by commonly used search engines were assessed for quality and medical accuracy.

Methods: The word scoliosis was entered into top six search engines and Websites ranked according to frequency. Five websites from the worldwide web and five from the UK only search were evaluated by medical professionals – 4 spinal consultants, 2 registrars, 3 nurses and 1 physiotherapist. 10 patients/carers who had scoliosis surgery also assessed these sites. A scale of 1 to 5 was used for ease of understanding, reliability, clinical correlation, adequacy and links and average score calculated.

Results: None of the top five UK websites figured in the top 5 WWW searchs. Scoliosis research society (SRS) and American Academy of Orthopaedic Surgeons (AAOS) website scored the highest by clinicians and patients in the www list. From the UK list, SAUK website scored the highest with both groups followed by Great Ormond Street Hospital (GOSH) website. We compared the assessment of websites by a healthcare professionals and by patients who had undergone treatment and showed no statistical difference in the scoring.

Conclusion: As treating clinicians it is necessary to educate patients by guiding them to reliable internet sites like SAUK and SRS.

Objective: Prolonged waiting time after being referred for a specialist opinion has plagued the NHS despite pressures to deliver optimum healthcare. We have assessed changes in clinical situation in patients referred to a spinal service while awaiting the first assessment.

Materials & Results: 89 patients were referred to our unit between Jan 2001 and December 2004. The gender distribution in this cohort was equal and the mean age was 50.7 yrs. The mean delay for being seen in the clinic was 28.4 mo (16–58 mo). Significant changes in the symptom pattern were noted in 46 patients, of which 8 patients reported radicular symptoms on a different side. In addition, 7 patients experienced an increased severity in the existing symptoms. 43 patients had been referred to us with an MRI. However due to the delay, 20 of these patients required re-scanning. Following the clinical assessment 25 patients were referred for Physiotherapy, 4 patients required a further clinical review and 44 patients were referred for further imaging.

Conclusion: The problem of excessive out-patient waiting time results in changes in symptom patterns and an increase in the severity of existing symptoms. The changes frequently results in an increased requirement of re-imaging.

Background data: The Paediatric Isola system uses the philosophy of torsion-countertorsion force as a means of scoliosis correction. It aims to maintain this correction till such time that definitive fusion can be carried out.

Aim: This is a retrospective case series of our experience with the Paediatric Isola system and we evaluated the results of this system in the treatment of Scoliosis of various etiologies.

Methods: Twenty –one children,5 with neuromuscular,1 with Ehler-Danlos,5 with idiopathic,3 syndromic and 7 congenital treated with the Isola Instrumentation were studied.

Average age was 6.5 years(2–12). Average follow-up was 24 months (6m-36m).

Results: The average Cobb angle was 52° before surgery, 33.7° after surgery (64 % correction) and 32.5° (62.5% correction) at latest follow-up. The mean apical vertebral translation was 86% and 84% at post-op and latest follow-up. Stabilisation was most commonly perfomed from T2 to L4/L5. Three patients had implant complications, two had deep seated wound infections which necesssiated removal of implants in one case. Five of these patients have gone on to definitive fusions. Curve correction was best for primary thoracolumbar curves and lumbar curves. 2 patients with thoracic curves did not maintain correction.

Conclusion: The Paediatric Isola system is a safe and effective instrumentation in early management of a difficult and challenging sub group of scoliosis patients.

Introduction: Restoration of vertebral height for burst fractures can be achieved either anteriorly, posteriorly or combined.

Aim: To biomechanically assess and compare stiffness of 1) posterior pedicle screws with Synex, 2) Synex+ Double screw+rod Ventrofix 3) Synex+ Double screw+ Single rod and 4) Synex+ Single screw+ Single rod in reconstructing an unstable burst fracture following anterior corpectomy.

Method: Fresh frozen calf lumbar spines (L3–L5) were dissected and L4 corpectomy performed. L3 and L5 were mounted on a plate and fixed. Loads were applied as a dead weight of 2Nm. The range of movement was measured using the Qualisys motion analysis system using external marker clusters attached to L3 and L5. Bony landmarks were identified with marker clusters as baseline. The movement was measured between the 2 marker clusters.

Five specimens were implanted for each group 1) with pedicle screw (into L3 and L5) and tested with/without Synex (expandable) cage anteriorly, 2) implanted with a Synex cage and Double screw+rod Ventrofix system, 3) Synex cage and Double screw+ Single rod Ventrofix construct and 4) Synex cage and Single screw+ Single rod Ventrofix system.

Results: Reconstruction of the anterior column with the combination of Synex and double rod Ventrofix produces a stiffer construct than the pedicle screw system in all planes of movement (p= 0.001 in rotation).

The double screw/ single rod system is less effective than the Ventrofix System but is comparable to the pedicle screw construct.

The single screw/ single rod construct leads to unacceptable movement about the axis of the inferior screw particularly in extension with a ROM much greater than the intact spine (p< 0.001)

Conclusion: Thus biomechanically we recommend Synex and double rod Ventrofix construct to reconstruct the anterior vertebral column following corpectomy for unstable burst fractures.

Aim: To determine the incidence of adjacent level osteophytes in patients who have had anterior cervical fusion using an anterior cervical plate as compared to those who are fused without an anterior cervical plate.

Design: We retrospectively reviewed the lateral radiograms of sixty two patients who have had an anterior cervical fusion with a minimum follow up of twelve months.

Materials and methods: We looked for the development of adjacent level osteophytes in these patients at their final follow up, which was generally at the time radiological fusion. There were 27 patients in the first group who had an anterior cervical plate used to fix the vertebrae in addition to the Cervios cage, while the 35 patients in the second group in whom only a Rabea cage was used for the fusion. The mean follow-up was 20.6 months (range 12–48).

Results: 64.3% of the patients who had an anterior cervical plate developed adjacent level osteophytes while none of the patients who have had the fusion without the cage developed the osteophytes.

Conclusion: We found the patients who had an anterior cervical interbody fusion using a plate had a significant risk of developing adjacent level osteophytes while this is not seen in patients who do not have the plate for the fixation.

Objective: To investigate the clinical outcomes, and the requirement of surgery following selective nerve root block performed for cervical radicular pain in patients with MRI proven disc pathology.

Methods: Thirty consecutive patients with cervical radiculopathy and correlating MRI pathology were studied. Mean age of patient was 46yrs (range 28–64yrs). Twenty nine of the thirty patients also complained of associated neck pain. All underwent fluoroscopically guided, selective cervical nerve root block with steroid (20mg Depomedrone) and local anaesthetic (0.5ml Bupivo-caine 0.25%). Radiographic contrast was used to confirm needle position. All procedures were conducted by the same clinician.

Pre and post procedure pain and physical function scores were noted using the standard SF 36 questionnaire, as well as whether subsequent surgery was required. Mean follow up time was seven months (range 2–13 months).

Results: 81% of patients reported an improvement in arm pain, and 66% in neck pain following the procedure. 77% of patients had an improvement in pain score (mean improvement 16 points). 68% of patients had an improvement in physical function score (mean improvement 20 points). At the time of follow up only one patient had undergone surgery for cervical radicular pain.

Conclusion: This study suggests that fluoroscopically guided selective nerve root block is a clinically effective interventional procedure in the management of cervical radicular pain, and may prevent the need for open surgery.

We have examined the outcome in 19 professional rugby union players who underwent anterior cervical discectomy and fusion between 1998 and 2003. Through a retrospective review of the medical records and telephone interviews of all 19 players, we have attempted to determine the likelihood of improvement, return to professional sport and the long-term consequences. We have also attempted to relate the probability of symptoms in the neck and radicular pain in the arm to the position of play. Neck and radicular pain were improved in 17 patients, with 13 returning to rugby, the majority by six months after operation. Of these, 13 returned to their pre-operative standard of play, one to a lower level and five have not played rugby again. Two of those who returned to the game have subsequently suffered further symptoms in the neck, one of whom was obliged to retire. The majority of the players with problems in the neck were front row forwards.

A return to playing rugby union after surgery and fusion of the anterior cervical spine is both likely and safe and need not end a career in the game.

This prospective randomized multicenter study compares two methods of bone defect treatment in tibial plateau fractures: a bioresorbable calcium phosphate paste (Alpha-BSM) that hardens at body temperature to give structural support versus Autogenous iliac bone graft (AIBG).

One hundred and eighteen patients were enrolled with a 2:1 randomization, Alpha-BSM to AIBG. There was a significant increased rate of non-graft related adverse affects and a higher rate of late articular subsidence (three to nine month period) in the AIBG group.

A bioresorbable calcium phosphate material is recommended in preference to the gold standard of AIBG for bone defects in tibial plateau fractures.

This prospective randomized multicenter study was undertaken to compare two methods of bone defect treatment: a bioresorbable calcium phosphate paste (Alpha-BSM –DePuy, Warsaw, IN) that hardens at body temperature to give structural support and is gradually resorbed by a cell-mediated bone regenerating mechanism versus Autogenous iliac bone graft (AIBG).

One hundred and eighteen adult acute closed tibial plateau fractures, Schatzker grade two to six were enrolled prospectively from thirteen study sites in North America from 1999 to 2002. Randomization occurred at surgery with a FDA recommendation of a 2–1 ratio, Alpha BSM (seventy-eight fractures) to AIBG (forty fractures). Only internal fixation with standard plate and screw constructs was permitted. Follow-up included standard radiographs and functional studies at one year, with a radiologist providing independent radiographic review.

The two groups exhibited no significant differences in randomization as to age, sex, race, fracture patterns or fracture healing. There was however, a significant increased rate of non-graft related adverse affects in the AIBG group. There was an unexpected significant finding of a higher rate of late articular subsidence in the three to nine month period in the AIBG group.

Recommendations for the use of AIBG for bone defects in tibial plateau fractures should be discouraged in favor of bioresorbable calcium phosphate material with the properties of Alpha BSM. We believe further randomized studies using AIBG as a control group for bone defect support of articular fractures are unjustified.

A bioresorbable calcium phosphate material is recommended in preference to the gold standard of AIBG for bone defects in tibial plateau fractures.

Funding: DePuy, Warsaw, IN.

Background: More patients are turning to the Internet for health-related information. Studies indicate that this information is being used to make decisions about their management. The aim of this study was to assess the information available specific to scoliosis on the Web using four common search engines.

Methods: Four search engines (Google, Yahoo, Hotmail and Ask Jeeves) were used in scanning the Web for the following key word- “Scoliosis”. Both U.K. only and World Wide sites were accessed. Four Spinal Surgery Consultants independently graded each site for layout, content, relevance to patients as opposed to medical professionals, ease of use and links to other sites. Each point was marked on a scale of 0–2 and a total of 10 points available. Web sites were assessed via U.K. search engines and forty via World Wide search engines. Good was awarded to a site with a score of 7–10; an average awarded for a score of 4–7 and poor was given to a site with a score of 0–4.

Results: For the U.K. search engines, twenty sites were evaluated and five common sites identified (spineuniverse.com, S.A.U.K.org, orthoteers.co.uk, B.O.A.ac. uk and scoilosis.info). From these sites only two were given a rating of good. For the World Wide Web search engines eighteen sites evaluated and seven common sites identified (SRS, spineuniverse.com, scoliosis.org, orthinfo.aaos.org, iscoliosis.com, scoliosisrx.com and scoliosis-world.com). From these sites four were given a rating of good. It was evident that the Scoliosis Association of United Kingdom did not appear in three of the search engines but only in Hotmail.

Conclusion: These results suggest that there are good sites available for patients to access information with regards to their condition and treatment options but there are also very poor sites available where incorrect information is available. Commonly, unfamiliar users of the Web will not search U.K. sites specifically and could easily miss the S.A.U.K. site, which is an excellent site and was one of the two sites via the U.K. search engine awarded a good score. Obviously, there were more good sites via the World Wide Web due to the American healthcare system. We recommend that leaflets should be available to parents and patients with scoliosis with information from the BSS of the condition and available Web sites with good ratings. Also we recommend that these sites be linked to the Royal College of General Practitioners Web site to provide reference on good practice.

Introduction: (1) Determine whether initial MRI findings correlate with clinical outcome.(2) Study the reproducibility of MRI measurements of large disc prolapses.(3) Estimate the ability to predict CES based on MRI alone.(4) Does CES only occur in degenerate discs?

Method: 31 patients with CES were identified and invited to attend clinic. 19 patients who underwent discectomy were identified. Digital photographs of all 50 MRIs were obtained. Observers: 1 Radiologist, 2 Spinal Surgeons and 1 Trainee did not know the number of patients in each group. Observers estimated the percentage spinal canal compromise on each view (0–100%), indicated whether they thought the scan findings could produce CES and commented on disc degeneration. Measurements were repeated after 2 weeks.

Results: 26 patients attended clinic – mean follow up 51 months (range 25–97). 12 of the 26 patients with CES had, on average, > 75% canal compromise. No significant correlations were found between MRI canal compromise and clinical outcome. Kappa values for intra-observer reproducibility of measurements ranged from 0.4–0.85 and inter-observer 0.63–5. Based on MRI, the correct identification of CES has sensitivity 68%, specificity 78%, positive predictive value 84% and negative predictive value 58%. Over 80% of the CES causing discs were degenerate.

Discussion: Canal compromise does not appear to predict clinical outcome. MRI measurement reproducibility has substantial agreement. CES is a clinical diagnosis supported by an MRI scan. In less clear cases the presence of a large disc on an MRI scan supports a diagnosis of CES (PPV 84%). CES occurs in degenerate discs.

Background: Campbell et al from Texas have pioneered the use of Vertical Expandable Prosthetic Titanium Rib (VEPTR) in congenital scoliosis. Our centre is the first in the UK to use it and we report our experience of 5 cases done in the past 2 years. VEPTR works on the principle of expansion thoracoplasty and thoracic spinal growth of upto 0.8 cms/year has been reported by the developers of this device.

Methods: This case series includes one child who had the index surgery in America and is undergoing sequential expansion in Cardiff. All surgeries were done using a standard technique with monitoring of somatosensory evoked potentials. After appropriate soft tissue and bony releases, VEPTR was inserted and expanded by 0.5 cms to maintain tissue tension. Subsequent expansions were done as day case surgeries at 4–6 month intervals through a small incision over the VEPTR. We assessed clinical and radiographic assessment, which included – hemithorax height ratio, Cobb angle, interpedicular line ratio, space available for the lung.

Results: There were 3 males and 2 females with mean age of 6.3 years (range 0.9 to 9 years) at the time of index operation. Average follow up is 2 years (0.4 to 5 years). Average hospital stay for the index surgery was 5 days (4–7 days). All patients had mean of 3 expansions (range: 0–6). Mean improvement in the Cobb angle was seen from 48° to 36° at last followup. Space available for lung improved from a mean of 72 % to 86 %. Mean improvement in hemithorax height ratio was from 72.5% to 86%. One child had mild pain due to prominent metalwork; 2 children had transient brachial plexus neurapraxia, one of whom had progression of a secondary cervical curve and is awaiting further surgery for the same.

Conclusion: Our early results show good improvement of clinical and radiographic parameters. Transient nerve palsies have been well reported on the concave side and occur due to traction on the nerves as a result of increased height of the thoracic cage. This occurred in one initial case and has not been seen later. These results are encouraging but do indicate a learning curve.

Purpose: To quantify the functional outcome of patients who were known to have sciatic nerve involvement pre-operatively and went on to have nerve preserving surgery utilising a planned marginal excision with epineurectomy.

Materials and Methods: Ten patients with large volume posterior thigh soft tissue sarcoma with known sciatic nerve involvement were reviewed between 1997 and 2004. Nine underwent surgery with extended epineurectomy of the sciatic nerve and planned marginal excision.

All patients underwent staging and follow up at Sarcoma Clinic with functional assessment and TESS evaluation.

Results: There were seven low and two high grade posterior thigh tumours of which nine were liposarcoma and 1 haemangiopericytoma. Two were recurrent and eight primary. There were five men and five women with a mean age of 77.

Nine patients underwent planned marginal excision. Sciatic nerve involvement was 13–30cm in eight cases and in one case the sciatic nerve was abutting the tumour throughout its length. There was soft tissue reconstruction in three cases using fascial adductor or gracilis graft for sciatic nerve cover and one with superficial femoral nerve and vein resection requiring ipsilateral saphenous reconstruction. The remainder underwent direct primary reconstruction.

Four patients underwent radiotherapy 46–60 Gy.

There was no local recurrence of disease within 14 – 96m follow-up. There was one patient with post radiation wound breakdown that resolved.

Three patients have died of unrelated causes. To date there has been no evidence of local recurrence of disease at FU.

Conclusion: Planned marginal excision of low grade large volume posterior thigh sarcomas with extensive sciatic nerve involvement can be successfully treated with preservation of the sciatic nerve without significant morbidity and resultant good limb function.

Background: A 9- year-old child with osteogenesis imperfecta and severe cervical kyphosis associated with wedged vertebrae and progressive neurological deterioration is presented. There is no report of upper cervical kyphosis associated with wedged vertebrae in osteogenesis imperfecta in the literature. We discuss the methods and difficulties in the surgical management of this condition and to highlight the appropriate surgical approach.

Methods: Methods:A 9-year-old girl presented with progressive cervical kyphosis and quadriparesis. At the age of 3 years she underwent posterior cervical fusion (C1–C6) for instability and deformity. Radiological and laboratory investigations confirmed the diagnosis of osteogenesis imperfecta. Radiographs of the cervical spine revealed a kyphotic deformity of 120° Magnetic Resonance Imaging (MRI) and Computerised Tomography (CT) scans showed anterior cord compression due to wedged vertebrae at C3 and C4. MRI-Angiography was performed pre-operatively to identify the anatomical position of the vertebral arteries. A modified anterolateral approach to the upper cervical spine was performed. Anterior C3 and C4 corpectomies with interbody fusion with cage and plate fixation was carried out.

Results: Postoperatively the patient made a full neurological recovery and significant correction of the deformity was achieved and correction was maintained at final follow-up.

Conclusion: Cervical kyphotic deformity in Osteogenesis Imperfecta is uncommon. Association of this condition with wedged vertebrae is rare. Surgical decompression of the upper cervical spine with severe kyphosis is a challenging problem. Which surgical approach should be used is controversial? There are difficulties exposing wedged vertebrae by a standard anterior or chin split approach to perform vertebrectomy. Costo-transversectomy has been used successfully in patients with Gibbous deformity in the thoracic spine but due the presence of vertebral artery in the cervical spine posterolateral approach is impossible. We have used a modified anterolateral approach to overcome this problem. Spinal stabilisation in children with Osteogenesis Imperfecta and poor bone quality is another challenge. We have used a small diameter MOSS cage with maxillofacial plate and screws to achieve stabilisation and fusion. The purpose of this report is to highlight the importance of diagnosis of progressive cervical kyphotic deformity in children with osteogenesis imperfecta and also to describe the difficulties encountered with surgical management of this condition.

Background: Type II odontoid fractures are the commonest upper cervical spine injury in the elderly, following minor falls. Structural heterogeneity within the axis with deficiency of bone mass in the base of the odontoid process has been attributed for these fractures.

Aims: To analyse whether osteoporosis at the dens-body junction is directly related to the occurrence of odontoid fractures in the elderly.

Material and Methods: We studied the reformatted CT scan images of 36 patients over the age of 70 years who had cervical spine injuries following minor trauma. In all these patients the severity of osteoporosis at the dens-body junction, and in the peg and body of axis were evaluated. The osteoporosis was graded into none, mild, moderate and severe. Statistical analysis was performed using Pearson’s Chi-square test to find the significance of osteoporosis at the dens-body junction in producing Type II odontoid fractures in the elderly.

Results: Type II odontoid fractures was seen in 21 patients. Eleven of the 21 patients with Type II fractures and eight of the 15 patients with no Type II odontoid fractures had significant osteoporosis at the dens-body junction. Five patients with Type II fracture and eight patients with no Type II fractures had significant osteoporosis at the dens and body of axis. Statistical analysis showed that the osteoporosis at the dens-body junction was not significant in patients with Type II odontoid fracture compared to those with no Type II odontoid fracture (χ² = 1.1; df = 3, p = 0.78).

Conclusions: Eventhough osteoporosis is one of the factors that increase the incidence of Type II fractures of the odontoid process in the elderly, it is not a direct aetiological factor.

Background: Long waiting lists in the NHS are a cause for public concern especially with regards to progressive conditions like scoliosis. We reviewed records to 61 patients to ascertain whether waiting time had any detrimental influence on their surgical management.

Methods: Retrospective review. Assessment of clinical records and radiographs of 61 patients who had scoliosis surgery over past two years was done by two independent investigators. Patient demographics, waiting times between referral and outpatient review and waiting time for surgery were collected.

Results: There were 41 females and 20 males with mean age of 11.8 years (range, 1– 22 years). Thirty-four patients had thoracic curves (28- right sided), 21 had thoracolumbar curves (19- right sided) and 6 patients had right sided lumbar curves. Mean Cobb angle at presentation was 58° (range,17°–90°) which increased to 71°(range, 30°–120°) at surgery. Average waiting time to be seen in the clinic was 16 months. Average waiting time for surgery was 10 months. Rapid curve progression was seen in twelve patients (20%), of which 10 required more extensive surgery than originally planned. Their mean Cobb angle at presentation was 48° (range, 45°– 80°), which increased to a mean of 59° at surgery (range, 50°–92°). At presentation their Risser grades were: 5 – grade 0, 3- grade 2, 2- grade 4. These 10 patients had waited averagely 7.8 months to be seen in the clinic and for 11 months to have the surgery.

Conclusion: Significant curve progression occurred in 20 % of patients waiting to have scoliosis surgery. Ten of those required much more extensive surgery than originally planned. Long waiting times therefore have a detrimental effect on the surgical management of scoliosis patients.

Aim: To review our series of mid foot sarcomas with regard to excision of tumour, tolerance of radiotherapy and preservation of function.

Methods and results: We identified 6 patients with mid foot sarcomas treated in our unit. Synovial sarcoma was the commonest diagnosis. All the patients had stage 1 disease with no evidence of pulmonary metastases at presentation. Patients judged to have resectable tumour but preserving sufficient foot to be functional were spared amputation. They had excision of the sarcoma and immediate reconstruction using fascio-cutaneous free flaps. Complete excision was achieved in all cases. One flap was lost and repeated. In all patients, subsequent radiotherapy was well tolerated without significant complications. All patients remain disease free. All patients have returned to pre-operative functioning including walking and jogging. All except one have returned to work.

Conclusion: Patients and feet treated by wide local excision of mid foot sarcomas and reconstructed by free fascio-cutaneous flaps tolerate post-operative radio-therapy well, and return to near normal function.

Background: Type II odontoid fractures are the commonest upper cervical spine injury in the elderly, following minor falls. Structural heterogeneity within the axis with deficiency of bone mass in the base of the odontoid process has been attributed for these fractures.

Aims: To analyse whether osteoporosis at the dens-body junction is directly related to the occurrence of odontoid fractures in the elderly.

Material and Methods: We studied the reformatted CT scan images of 36 patients over the age of 70 years who had cervical spine injuries following minor trauma. In all these patients the severity of osteoporosis at the dens-body junction, and in the peg and body of axis were evaluated. The severity was graded into none, mild, moderate and severe, depending on the cortical thickness, trabecular pattern, and the size of holes (absence of trabeculae) using sagittal, coronal and transverse sections of CT scan pictures. The osteoporosis was graded into none, mild, moderate and severe. Statistical analysis was performed using Pearsons Chi-square test to find the significance of osteoporosis at the dens-body junction in producing Type II odontoid fractures in the elderly.

Results: Type II odontoid fractures was seen in 21 patients. Eleven of the 21 patients with Type II fractures and eight of the 15 patients with no Type II odontoid fractures had significant osteoporosis at the dens-body junction. Five patients with Type II fracture and eight patients with no Type II fractures had significant osteoporosis at the dens and body of axis. Statistical analysis showed that the osteoporosis at the dens-body junction was not significant in patients with Type II odontoid fracture compared to those with no Type II odontoid fracture (Chi-square value = 1.1; df = 3, p = 0.78).

Conclusions: Eventhough osteoporosis is one of the factors that increase the incidence of Type II fractures of the odontoid process in the elderly, it is not a direct aetiological factor.

We propose a grading system for contrast free MRI images of tennis elbow and evaluate the inter and intra observer variability of their interpretation.

Methods: Three senior orthopaedic surgeons were asked to blindly grade 0.2T dedicated extremity contrast free MRI images of elbows of patients who presented with varying degrees of symptomatic tennis elbow.

Our proposed grading system of 1 to 5 based on the pattern around the common extensor tendon was used.

Images of the symptomatic and contralateral non symptomatic elbows were graded blindly twice with an interval of 1 month by each surgeon.

Each surgeon graded 176 MRI images twice.

The grades were subsequently grouped into (I) grades 1 to 2 and (II) grades 3 to 5

Results: With regards to the intra observer agreement, consultant A showed 90.1% agreement, consultant B showed 90.6% agreement and consultant C 96.0% agreement. The mean intra observer agreement rate was 92.2%.

The inter observer agreement between consultant A and B was 82.46%, between A and C 67.1% and between B and C 80.1%.

It was also noted that there were systematic differences to the inter observer variability. Consultant A graded the images 3 to 5 on both occasions 52.9% of the time, consultant B graded 3 to 5 on both occasions 37.8% of the time and consultant C graded 3 to 5 on both occasions 23.3% of the time.

Conclusion: The intra observer agreement rate is high. There is however a greater inter observer variation but this variation is consistent. We suggest that the inter observer differences can be improved by (1) reducing the grades to positive or negative and (2) by group reeducation of the observers.

Introduction: Current evidence suggests that CES should be operated within 48 hours from onset of sphincteric symptoms in order to maximise chances of recovery. Measurement reproducibility of large disc prolapses and clinical correlations have not previously been studied.

Objectives: (1) Determine whether initial MRI findings correlate with clinical outcome (2) Study the reproducibility of MRI measurements of large disc prolapses (3) Estimate the ability to predict CES based on MRI alone.

Study Design: 31 patients with CES were identified, the case notes reviewed and the patients invited to attend clinic. Outcome consisted of history and examination, and several validated questionnaire assessments. 19 patients who underwent discectomy for persistent radiculopathy were identified. None had sphincteric symptoms. All had a significant surgical target. Digital photographs of all 50 MRIs were obtained showing the T2 mid-sagittal image and the axial image with the greatest disc protrusion. The Observers: 1 Consultant Radiologist, 2 Consultant Spinal Surgeons and 1 SHO did not know the number of patients in each group. Observers estimated the percentage spinal canal compromise on each view and indicated whether they thought the scan findings could produce CES. Measurements were repeated after 2 weeks.

Results: 26 patients attended clinic mean follow up 51 months (25 to 97). As expected, the % canal compromise differed significantly between the two groups (p0.001). 12 of the 26 patients with CES had, on average, over75% canal compromise. No significant correlations were found between MRI canal compromise and clinical outcome. Canal compromise did predict whether the patient would fail their Trial Without Catheter (p0.05). Based on MRI alone, the correct identification of CES has sensitivity 68%, specificity 78%, positive predictive value 84% and negative predictive value 58%. Kappa values for intra-observer reproducibility ranged from 0.4 to 0.85 for sagittal compromise, axial compromise and correct prediction of CES. All three interobserver kappa values for these measurements were 0.64.

Conclusions: This is the largest radiological case series of CES with 4 years clinical follow up. Canal compromise on MRI does not appear to directly predict clinical outcome. Reproducibility of MRI measurements of large disc protrusions has substantial agreement. MRI could be of help in equivocal cases if the scan shows a large disc.

Study Design: Retrospective Series.

Objectives: To analyse loss of correction of the anterior wedge angle and the components responsible for the recurrence of kyphosis after surgical stabilisation of dorsolumbar fractures, and to assess the return of functional capacity in these patients.

Materials and Methods: Between January 1998 and March 2003, 34 patients had posterior stabilisation performed with the Universal Spine System (Synthes) for dorsolumbar fracture at a single level with no neurological deficit. There were 26 AO Type A fractures, 5 Type B fractures, and 3 Type C fractures. Serial standing lateral radiographs were taken from the immediate postoperative period to the most recent follow-up. The anterior wedge angle, the heights of the discs above and below the fractured vertebra, and the heights of the vertebral bodies above, at, and below the fractured level were measured. The height at each level was measured in three segments (anterior, middle and posterior). The values were normalised to avoid discrepancies while comparing radiographs. The difference in the height of each segment measured between the immediate postoperative period and the most recent follow-up were computed. Short Form 36 (SF-36) was used to assess the functional outcome in each.

Results: The mean follow-up period was 23.6 months (9 to 48 months). The mean anterior wedge angle was 10.1 ± 7.2 degrees in the immediate postoperative period and 17.1 ± 10.9 degrees at latest follow-up (p< 0.001). The mean loss of correction was 7.0 ± 8.5 degrees (−11 to 24) and this showed a linear relationship to the preoperative anterior wedge angle. Furthermore there was a linear increase in the loss of correction of the angle as the follow-up period increased. The correlation between the corresponding difference in the height of each segment and the degree of loss of correction of the anterior wedge angle showed significant correlation to the decrease in the anterior segment height at the fractured vertebral body level (Pearson’s coefficient r=0.53 significant at 0.01 level, p=0.001). The mean physical function score from SF-36 was 56.3 and the mean bodily pain score was 49.7. There was no relationship to the angle of kyphosis at follow-up to the physical function score (r=0.12, p=0.50) and the bodily pain score (r=0.14, p=0.44).

Conclusions: There is a progressive loss of correction (increasing kyphosis) after posterior stabilisation with instrumentation that roughly approximates the initial decrease in anterior height of the fractured vertebral body. The degree of loss of correction does not depend on the type of fracture. The loss of correction is related to the preoperative angle of kyphosis.

Study Design: Retrospective review.

Objectives: Rugby union has recently become a highly-paid professional sport. Players requiring anterior cervical discectomy wish to know the effect this will have on their career. To answer this question, the result of the above procedure in professional rugby players was studied.

Methods: A retrospective notes review and telephone interview were conducted on 19 professional rugby players who had a cervical discectomy between 1998 and 2003. Pre and post operative symptoms and numbers returning to rugby after surgery were assessed.

Results: Neck pain was eradicated in eight (42%) of the players, nine (47%) achieved partial relief and two were not helped. Brachalgia was eradicated in fifteen (79%) individuals, improved in two (10.5%) and two (10.5%) had no relief. Fourteen (74%) returned to rugby union, the majority at six months post operatively (range – five to 17 months). Thirteen (68.5%) returned to their pre-operative level of rugby; one dropped to a lesser division and five have never played rugby again (three due to physical inability, one due to club reluctance to insure and one because of a separate injury). Two of the players that returned to rugby have subsequently retired because of neck symptoms. They played three and two years post-operatively at first-class level.

Conclusion: Return to rugby union after anterior cervical discectomy is both likely and safe and therefore need not be a career ending procedure.

Study Design. A reliability study of the Modic classification.

Objective. To determine the reliability and reproducibility of the Modic classification for lumbar vertebral marrow changes.

Summary of Background data. In 1988, Modic with colleagues described two degenerative stages of vertebral marrow and endplate morphology. These were Type I (inflammatory phase) and Type II (fatty phase). Later in 1988, he added a third variety; Type III where there was marked sclerosis adjacent to the endplates. No formal reliability or reproducibility studies had been performed on the Modic classification.

Methods. This study involved five independent observers of differing spinal experience using the Modic classification to grade fifty sagittal T1 and T2 weighted MRI scans. The observers repeated the assessment at three weeks. Intra- and inter-observer reliabilities were assessed using kappa statistics.

Results. There were 7 type I, 40 type II, 1 type III and 2 normal levels. The individual intra-observer agreement was substantial or excellent with kappa values ranging from 0.71 to 1.00. The overall inter-observer agreement was excellent with a kappa value of 0.85. There was complete agreement in 78% of the levels, a difference of one type in 14% and a difference of two or more in 8% of levels. The level of experience of the observer did not correlate with a better score.

Conclusions. We have shown that the Modic classification is both reliable and reproducible. It is simple and easy to apply for observers of varying clinical experience. We therefore recommend its use in clinical research and practice.

Introduction and Aims: Odontoid fractures are quite common in the elderly following minor falls. As there are a few articulations in the upper cervical spine, degeneration in any one particular joint may affect the biomechanics of loading of the upper cervical spine. We aimed to analyse the pattern and relationship of odontoid fractures to the upper cervical spine osteoarthritis in the elderly.

Method: Between July 1999 and March 2003, 185 patients had CT scan of the cervical spine for cervical spine injuries. Twenty-three out of 47 patients over the age of 70 years had odontoid fractures. The CT scan pictures of these patients were studied to analyse the type of fracture and its displacement, the severity of osteoarthritis in each articulation in the upper cervical spine, namely lateral atlantoaxial, atlantooccipital, atlantoodontoid and subaxial facetal joints, evaluation of osteopenia in the dens-body junction and in the body and odontoid process of the axis, and calcification of the ligaments.

Results: Twenty-one of the 23 patients had Type II odontoid fracture with posterior displacement in seven (33.3%) and posterior angulation in nine (42.8%) patients. In these patients with Type II dens fracture, the atlantodens interval was obliterated in 19 (90.48%) patients, with only two of them (9.52%) having lateral atlantoaxial osteoarthritis.

Conclusion: Type II fracture is the commonest odontoid fracture in the elderly. Posterior displacement of the fracture is common in elderly, unlike the younger population. There is a significant relationship between the upper cervical spine osteoarthritis, apart from osteopenia, to the incidence of Type II odontoid fractures. Significant atlantoodontoid osteoarthritis in the presence of normal lateral atlantoaxial joints increases the risk of sustaining Type II odontoid fracture.

Introduction: Current evidence suggests CES should be operated < 48 hours from onset. MRI scanning is often not available 24 hours a day.

Objectives: (1) Determine whether MRI findings correlate with clinical outcome. (2) Study the reproducibility of MRI measurements of large disc prolapses. (3) Estimate the ability to predict CES based on MRI alone.

Study Design: 31 CES patients were identified,contactedand invited to follow up. Clinical outcome consisted of history and examination, and validated questionnaire assessments. 19 patients who underwent discectomy were identified. T2 mid-sagittal and axial digital photographs of all 50 MRIs were obtained. Observers did not know the number of patients in each group (1 Consultant Radiologist, 2 Consultant Spinal Surgeons and 1 SHO). They estimated the percentage spinal canal compromise on each view (0–100%) and indicated whether they thought the scan findings could produce CES. Measurements were repeated after 2 weeks.

Results: 26 patients attended clinic (mean follow up 51 months). There were no significant correlations found between MRI canal compromise and clinical outcome. Kappa values for the measurements ranged 0.52–0.85 and 0.61–0.75 for intra- and inter-observer reproducibility. Based on MRI alone correct identification of CES has sensitivity 67%, specificity 81%, positive predictive value 85% and negative predictive value 60%.

Conclusions: Canal compromise on MRI does not predict the outcome of patients with CES. Reproducibility of MRI measurements of large disc protrusions has substantial agreement. MRI could be of help in equivocal cases if the scan shows a large disc.

Over a five year period 50 patients required combined orthoplastic care out of 987 patients presenting with bone and soft tissue tumours. Thirty men, mean age 51 years, had their treatment reviewed at a mean follow up of 23 months (3–54 months) post surgery. All surviving patients completed the Toronto Extremity Salvage Score.

There were 23 bone and 27 soft tissue sarcomas, 4 were Enneking stage I, 41 stage II and 5 stage III. All tumours were removed by wide resection to achieve microscopically clear margins in 49. 9 endoprostheses were inserted. Soft tissue reconstruction involved 9 local flaps, 13 distant flaps (mainly muscle) and 8 free flaps (including 3 composite osseous flaps). 20 patients received adjuvant radiotherapy and 14 patients received chemotherapy.

Two endoprosthetic replacements required surgery for infection, one distant lap and one free flap required further surgery (6%). The mean disease free interval was 29 months (2–49 months). There were 6 deaths and pulmonary metastases occurred in a further 8 patients. Within this study period there was one episode of local recurrence, but no local recurrence in the group that had radiotherapy. 77% of surviving patients completed the Toronto Extremity Salvage Score and good to excellent function was seen in most cases.

Combined orthoplastic approach facilitates limb sparing surgery and early adjuvant radiotherapy.