Introduction

Pain after trauma has received relatively little research attention compared with surgical techniques and functional outcomes, but is important to patients. We aimed to describe nerve dysfunction and pain characteristics using tibial fractures as a model. We hypothesized that early nerve dysfunction was associated with neuropathic and chronic pain.

Background

Conventional instrumented total knee arthroplasty uses fixed angles for bony cuts followed by soft tissue releases to achieve balance. Robotic-assisted surgery allows for soft tissue balancing first then bony resection. The changes to the implant position from conventional instrumented surgery were measured and recorded.

Purpose

Back pain is the primary cause of disability worldwide yet surprisingly little is known of the underlying pathobiology. We conducted a genome-wide association study (GWAS) meta-analysis of chronic back pain (CBP). Adults of European ancestry from 15 cohorts in the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium, and UK Biobank were studied.

Background: The results of arthroscopic anterior labral (Bankart) repair have been shown to have high failure rate in patients with significant glenoid bone loss. Several reconstruction procedures using bone graft have been described to overcome the bone loss, including autogenous coracoid transfer to the anterior glenoid (Latarjet procedure) as well as iliac crest autograft and tibial allografts. In recent years, trends toward minimally invasive shoulder surgery along with improvements in technology and technique have led surgeons to expand the application of arthroscopic treatment. Purpose: This study aims to perform a retrospective analysis of prospectively collected data to evaluate the clinical and radiological follow up of patient who underwent anatomic glenoid reconstruction using distal tibia allograft for the treatment of shoulder instability with glenoid bone loss at 1-year post operation time point.

Between December 2011 and January 2015, 55 patients underwent arthroscopic stabilisation of the shoulder by means of capsule-labral reattachment to glenoid ream and bony augmentation of glenoid bone loss with distal tibial allograft for recurrent instability of the shoulder. Preoperative and postoperative evaluation included general assessment by the western Ontario shoulder instability index (WOSI) questionnaire, preoperative and postoperative radiographs and CT scans.

Fifty-five patients have been evaluated with mean age of 29.73 years at time of the index operation. There were 40 males (mean age of 29.66) and 15 female (mean age of 29.93). Minimum follow up time was 12 months. The following adverse effects were recorded: none suffered from recurrent dislocation, 2 patients suffered from bone resorption but without overt instability, 1 patient had malunion due to screw fracture, None of the patients had nonunion. The mean pre-operative WOSI score was 36.54 and the mean postoperative WOSI score was 61.0.

Arthroscopic stabilisation of the shoulder with distal tibia allograft augmentation demonstrates promising result at 1year follow up.

Purpose

Prospectively evaluate the timescale of leg pain resolution after lumbar discectomy and decompression, in the immediate post-operative period and identify possible risk factors for failure/delay in leg pain resolution.

It is generally accepted that Hip-Knee-Ankle (long-leg) radiographs are a good measurement tool for biomechanical axis of the knee and they have been used as the outcome measure for many studies. Most of the surgeons recommend having pre operative and post operative long leg radiographs for total knee replacement surgery, although practice is not as common. We studied the biomechanical axis on long-leg films and compared it with computer navigation.

The objectives were to find out repeatability of measurements of biomechanical axis with inter observer readings on long leg radiographs and to compare biomechanical axis measurements with Navigation values obtained during total knee replacement surgery.

Our institution routinely uses long-leg radiographs for total knee replacement (TKR) surgery both pre- and post-operatively. A series of 209 patients who had navigated TKR between Jan 2007 and 2008 were selected. Stryker and Orthopilot systems for navigation were used. The intra-operative biomechanical axis measurements from the computer navigation files both pre-and post- implant were recorded. The long leg films were measured with a defined protocol from the digital images on PACS system. Centre of the head of femur was taken as the upper point. For the knee centre the midpoint of a line joining the distal femoral notch centre and upper tibia was used. For the ankle centre midpoint of the upper talar margin was used. An angle between the three points represented the radiological biomechanical axis. To investigate inter-observer error, two observers measured the pre- and post-operative biomechanical axis on long leg radiographs independently on 57 patients.

For the inter-observer measurements on 57 patients, the intraclass correlation coefficient was 0.99 for pre-operative radiographs and 0.98 for post-operative radiographs. Maximum difference between the two observers was 2° in four cases. All other cases showed the same readings or 1° difference.

There was a strong correlation, which was statistically significant, between the pre-operative radiographic and navigated measurements with Pearson correlation coefficient of 0.810 (p< 0.001). The maximum difference between the radiographic and navigated measurement was 24 degrees. The relationship between the postoperative measurements was weaker but statistically significant with Pearson correlation coefficient of 0.323 (p< 0.001). The maximum difference between the two methods of measurement was larger 15.5.

It can be concluded from this study that biomechanical axis on a long leg radiograph is a repeatable measure with good inter-observer correlation.

Although it is statistically significantly correlated with navigated readings, the absolute values may be different with both the methods. This raises the question on the reliability of long leg radiographs for the prediction of true biomechanical axis. Most of the larger value differences had a fixed flexion deformities (9 – 45 degrees). This can affect the readings on the long leg radiographs and make the deformity look either smaller or bigger. Also as our knee kinematic study has proven that the deformity does not remain the same in flexion as it was in extended knee that could also account for the difference in the readings. Other reasons for difference in the pre operative readings could be weight bearing status and surgical opening of the joint before taking the pre operative biomechanical axis measurements. Difference in the post operative readings could be attributed to weight bearing status, time length between navigation and radiographic measurements (6–12 wks), scarring of the soft tissues in the time and flexed posture of knee in the early post operative period.

It is generally accepted that Hip-Knee-Ankle (long-leg) radiographs are a good measurement tool for biomechanical axis of the knee and they have been used as the outcome measure for many studies. Most of the surgeons recommend having pre operative and post operative long leg radiographs for total knee replacement surgery, although practice is not as common. We studied the biomechanical axis on long-leg films and compared it with computer navigation. The aims were

To find out repeatability of measurements of biomechanical axis with inter observer readings on long leg radiographs

Our institution routinely uses long-leg radiographs for total knee replacement (TKR) surgery both pre- and postoperatively. A series of 209 patients who had navigated TKR between Jan 2007 and 2008 were selected. Stryker and Orthopilot systems for navigation were used. The intra-operative biomechanical axis measurements from the computer navigation files both pre-and post- implant were recorded. The long leg films were measured with a defined protocol from the digital images on PACS system. Centre of the head of femur was taken as the upper point.

For the knee centre the midpoint of a line joining the distal femoral notch centre and upper tibia was used. For the ankle centre midpoint of the upper talar margin was used. An angle between the three points represented the radiological biomechanical axis. To investigate inter-observer error, two observers measured the pre- and postoperative biomechanical axis on long leg radiographs independently on 57 patients. For the inter-observer measurements on 57 patients, the intraclass correlation coefficient was 0.99 for pre-operative radiographs and 0.98 for post-operative radiographs. Maximum difference between the two observers was 2° in four cases. All other cases showed the same readings or 1° difference. There was a strong correlation, which was statistically significant, between the pre-operative radiographic and navigated measurements with Pearson correlation coefficient of 0.810 (p< 0.001). The maximum difference between the radiographic and navigated measurement was 24 degrees. The relationship between the post-operative measurements was weaker but statistically significant with Pearson correlation coefficient of 0.323 (p< 0.001). The maximum difference between the two methods of measurement was larger 15.5.

It can be concluded from this study that biomechanical axis on a long leg radiograph is a repeatable measure with good inter-observer correlation. Although it is statistically significantly correlated with navigated readings, the absolute values may be different with each method. This raises the question of the reliability of long leg radiographs for the prediction of true biomechanical axis. Most of the larger value differences had a fixed flexion deformities (9 – 45 degrees). This can affect the readings on the long leg radiographs and make the deformity look either smaller or bigger. Also, our knee kinematic study has proven that the deformity does not remain the same in flexion and in the extended knee. This could also account for the difference in the readings. Other possible reasons for differences in the pre operative readings: the weight bearing status and the surgical opening of the joint, before taking the pre operative biomechanical axis measurements. Differences in the post operative readings could be attributed to: weight bearing status, time length between navigation and radiographic measurements (6–12 wks), scarring of the soft tissues in the meantime and flexed posture of knee in the early post operative period.

Introduction: The knee joint replacement arthroplasty is a very successful procedure. Traditionally we aim to perform the arthroplasty and recreate the patients’ biomechanical axis and correct the coronal plain alignment deformity. Unfortunately till recently there was no fine way of controlling the exact alignment and depending on surgeon to surgeon, a valgus (to anatomical axis) of 3 to 7 degrees is aimed for using mechanical intra or extramedullary jigs. On proper measurements only 70–80% of knees achieve the aimed result at best as can be seen in the literature. With the advent of computer aided navigation we can now achieve the desired alignment in a much higher percentage of patients.

Material: We performed 1000 total knee arthroplasties at our hospital. Out of these 500 were performed using computer navigation and 500 using conventional mechanical jigs. Pre op and post op long leg alignment films were taken using standardised method. The data was collected using oxford scores and from computer navigation machines and plain radiographic analysis. The observers doing the radiographic analysis were blinded as to whether the patient had procedure done by conventional means or by computer navigation. Sub grouping of the deformities was done depending on the amount of deformity.

Results: 500 patients had the operation done by conventional means and the other 500 with computer navigation guidance. Further subgroups were made depending on the amount of pre-existing radiological deformity 0–5, 6–10, 11–15 and more than 15 degrees of varus or valgus deformity. The effect of gender, bmi, surgeon experience, clinical oxford score outcome was also considered. It was clear that the patients who had more severe deformities and valgus deformities had better post operative alignments after the procedure was performed with computer navigation as compared with the conventional means. There was statistically significant difference observed between the subgroups.

Discussion: Orthopaedic surgery has improved with technical advancements over the number of years. With any new procedure it takes a long time to shed the old beliefs and adapt the new concepts. While we have plenty of evidence in literature and from our study that computer navigation can give better desired alignment after total knee arthroplasty especially with more severe deformities, it still needs to be taken up by majority of orthopaedic surgeons. Ours is the first study to demonstrate the difference in the specific subgroups.

This presentation introduces a new tool to be used in the cementing of acetabular components in total hip arthroplasty, the ‘Rim Cutter’. The Rim Cutter is designed to cut a ledge in the rim of the acetabulum into which a flanged cup can be cemented. The flange is trimmed such that it fits precisely into the ledge cut in the acetabulum. We present the in vitro pilot study of the effect of using this tool on the intra-acetabular cement mantle pressure during cup insertion and also the effect on the depth of cement penetration as the cup is inserted. A significant improvement in both cement pressure and cement penetration over conventional flanged and unflanged cups is noted. Improved cement penetration around the rim of the acetabulum in THR has implications for reducing the rate of aseptic loosening. The pilot study also suggests other beneficial features of using the rim cutter such as improved cup centralisation, control of orientation and the prevention of the cup ‘bottoming out’. Further in vivo studies are required to better assess its efficacy.

Introduction and Aims: The hypothesis that ‘utilisation of gradual distraction and soft tissue correction by external fixation improves outcomes in hand and wrist deformity’ was analysed in 29 extremities in 24 patients, to define the indications for gradual soft tissue correction of congenital and acquired deformity and distraction osteogenesis in hypoplastic digits.

Method: This retrospective review of 29 extremities in 24 patients evaluated the role of monolateral external fixators with uniplanar (n=20) and multiplanar (n=9) correction capability (Orthofix, International). Evaluation included an assessment of complications, patient satisfaction, functional outcome, and impact on health-related quality of life.

Results: The devices were successfully used to correct radial longitudinal deficiency of the radius (radial club hand) (n=9); digital hypoplasia (n=15) and wrist flexion contracture secondary to spasticity (n=5). There were no significant complications related to the devices. Pin track irritation and drainage occurred in two of 108 pins. One pin became loose and needed to be replaced, and one fixator required two intraoperative adjustments. Multiplanar fixators used for correction of radial club hands and wrist flexion contracture improved soft tissue position in allowing secondary bony procedures and/or tendon transfers. Distraction osteogenesis of metacarpals and phalanges (included seven previously transferred extraperiostial toe phalanges) was successful with an average lengthening of 2.1 centimetres.

Conclusion: Gradual distraction and soft tissue correction improves outcomes in congential and acquired hand and wrist deformity in children and adolescents. Mono-lateral fixation devices allow correction with hinges or gears, enhance correction of complex deformity, and is well tolerated by patients and caregivers.

Introduction and Aims: In order to evaluate the hypothesis that ‘Botulinum A Toxin (BoNT-A) improves function and health-related quality of life in patients and their caregivers’, the experience of a single institution that performed over 7500 injections in 515 patients was evaluated to provide safety data, injection guidelines, and current indications.

Method: This retrospective review utilised a computerised database that contains information from open-label trials (n=6), double-blind randomised trials (n=4), and cumulative treatment experience in 1100 children and adults with cerebral palsy. Standardised data collected over the past 15 years was analysed with respect to indications, complications, dosage, function, health-related quality of life of patients and their caregivers, rehabilitation (WeeFIM), gross motor function classification (GMFCS), and response rates. Pharmacoeconomic analysis was performed by linking with state Medicaid data.

Results: BoNT-A is safe and well tolerated. There were no systemic side effects in dosages ranging from four to 25 units per kilogram body weight. Standardised injection techniques included dilution from 10 to 100 units per cc with a maximum dose of six units per kilogram in a single muscle and 25 units per kilogram in a single patient. The maximum dose was 600 units.

Short-term response rates were 65–70%; intermediate response rates 45–50%. The most frequent complications were soreness of the injection site (15%) and transient weakness (2%). Ninety-five percent of injections were performed in the office without conscious sedation. Five percent were performed under general anaesthesia or with conscious sedation.

Based on these data, current indications include dynamic tone interfering with caregiver function (e.g., equinus gait), painful spasticity, post-operative spasticity, and pain management. Contraindications are failure to respond to previous injections. Pharmacoeconomic analysis diminished cost and improved function and quality of life of patients and/or caregivers.

Conclusion: Botulinum A Toxin is a safe and cost-effective drug in patients with cerebral palsy. Response rate is 50–70%. Optimal results are obtained with appropriate intramuscular localisation and sufficient volume to saturate neuromuscular junctions.

Introduction and Aims: In order to evaluate the hypothesis that the ‘temporary and controlled reduction of muscle force protects repair sites come from its safe, active, and passive range of motion and diminishes complications’, a tendon repair model was evaluated.

Method: After heel cord tenotomy, Sprague-Dawley rats (n=36) were randomised to Botulinum A Toxin at six units per kilogram or saline and the tendon repaired with a two-strand core suture and a peritenon running suture. The ankles were pinned in equinus for two days, and then the animals were allowed to move freely within their cages. Analysis included gap, rupture rates, electrophysiologic measurements and mechanical testing.

Results: The treatment group had a statistically significant lower spontaneous partial or total rupture rate than the control (P=0.38). Tendon electrophysiologic testing showed that the toxin group had lower twitch and tetanus values than the control group (evidence of effective denervation). The toxin group also had better histologic healing and better strength of repair (higher rupture strength values). Histologic assessment showed that the toxin-treated group had more normal histology with less scar.

Conclusion: Chemoprotection decreases significantly spontaneous tendon rupture rates following repair in active versus control groups. The active toxin group demonstrated better healing. Decreasing tension across repair sites is equally effective in increasing inastamotic strength and permits active range of motion without rupture.

Staphylococcus aureus is the bacterial pathogen which is responsible for approximately 80% of all cases of human osteomyelitis. It can invade and remain within osteoblasts. The fate of intracellular Staph. aureus after the death of the osteoblast has not been documented.

We exposed human osteoblasts to Staph. aureus. After infection, the osteoblasts were either lysed with Triton X-100 or trypsinised. The bacteria released from both the trypsinised and lysed osteoblasts were cultured and counted. Colonies of the recovered bacteria were then introduced to additional cultures of human osteoblasts.

The number of intracellular Staph. aureus recovered from the two techniques was equivalent. Staph. aureus recovered from time zero and 24 hours after infection, followed by lysis/trypsinisation, were capable of invading a second culture of human osteoblasts.

Our findings indicate that dead or dying osteoblasts are capable of releasing viable Staph. aureus and that Staph. aureus released from dying or dead osteoblasts is capable of reinfecting human osteoblasts in culture.

The aim of the study was to analyze the results of the Bayley-Walker Fixed Fulcrum Total Shoulder Replacement done at our institution.

We present a retrospective study of 13 Bayley-Walker Total Shoulder Replacement (BWTSR) with a short follow-up of three to 38 months. Indications for the surgery included severe pain, and all the patients had a dysfunctional rotator cuff not considered to be amenable to surgical repair. Five patients had had previous failed rotator cuff repairs. One patient had a shoulder dislocation following a rotator cuff repair. Not all patients had glenohumeral arthritis. Five males and eight females were treated with BWTSR with a mean age of 66.5 years. Eight patients had left sided BWTSR and five patients had right shoulders replaced. A McKenzie approach was most commonly employed. Post-operatively in most cases early assisted active mobilisation was encouraged.

The Oxford shoulder assessment questionnaire was used in the postoperative subjective assessment. Constant functional assessment score improved on average from 24.3 preoperative to 64.5 postoperative. Complications include significant glenoid fracture during surgery in three patients. One patient had significant infection which responded to treatment, the joint survived and the patient has a good result. One patient had dislocation of the UHDPE liner due to faulty technique.

We conclude that BWTSR is a reliable procedure in a painful rotator cuff deficient shoulder. In suitable patients better results can be achieved than with non-constrained prostheses. The worst results of BWTSR are comparable to the poor results of unconstrained replacement.