Introduction

Periprosthetic joint infection (PJI) can be difficult to diagnose. A variety of techniques have been described. The efficacy of the alpha-defensin laboratory test was examined and compared with other established modalities in the diagnostic workup of ‘real world’ arthroplasty patients.

The National Institute for Health and Clinical Excellence (NICE) has thus far relied on historical data and predominantly industry-sponsored trials to provide evidence for venous thromboembolic (VTE) prophylaxis in joint replacement patients. We argue that the NICE guidelines may be reliant on assumptions that are in need of revision. Following the publication of large scale, independent observational studies showing little difference between low-molecular-weight heparins and aspirin, and recent changes to the guidance provided by other international bodies, should NICE reconsider their recommendations?

Cite this article: Bone Joint Res 2014;3:146–9.

Commissioning for quality and innovation (CQUIN) guidelines specify that diaphyseal fractures of the tibia should be treated within 24 hours of admission. We aimed to identify our compliance at a Major Trauma Centre.

Restrospective analysis of all tibia fractures over 12 months. Fractures that were not diaphyseal nor open were excluded. Time of presentation, x-ray, arrival to ward and arrival in theatre were analysed against CQUIN guidelines.

43 fractures, 18 (42%) arrived in theatre for operative management within 24 hours. 15 (35%) were managed operatively in the subsequent 24 hours and 10 (23%) were managed after 48 hours. Average time to theatre was 38 hrs 37 mins (SD 29hrs 42mins). It took on average 51mins (SD 43 mins) for a patient to have an xray and 3 hrs 53 mins (SD 1hr 47mins) to arrive on the ward, and average 3 hrs 2 mins (SD 1hr 43mins) between xray and the ward.

42% of patients are making CQUIN standards for closed tibial shaft fractures. There are logistical and resource factors contributing towards this as well as clinical issues. To address this there needs to be an agreed multidisciplinary pathway developed to ensure compliance with CQUIN standards.

Background

Medical complications and death are rare events following elective orthopaedic surgery. Diagnostic and operative codes are routinely collected on every patient admitted to English NHS hospitals. This is the first study investigating rates of these events following total joint replacement (TJR) on a national scale.

Background

Medical complications and death are rare events following elective orthopaedic surgery. Diagnostic and operative codes are routinely collected on every patient admitted to hospital in the English NHS (hospital episode statistics, HES). This is the first study investigating rates of these events following total joint replacement (TJR) on a national scale in the NHS.

Unstable fractures of the distal tibia are being increasingly treated by open reduction and internal fixation using pre-contoured locking plates. Functional outcome following this type of fixation has not been reported previously.

The aim of this study was to functionally assess patients following MIPO fixation of distal tibial fractures.

Case notes of 26 patients treated at a single centre were reviewed. The fracture type, fixation technique, complications, time to union and subsequent treatment were documented. All patients returned for functional scoring using the validated American Academy of Orthopedic Surgeons (AAOS) foot and ankle core score.

Twenty-six consecutive patients were treated between 2002-2005. The majority were male, and 5 were open fractures. There were 13 AO type A, 4 type B and 9 type C fractures. Mean follow up was 20 months. Average time from injury to surgery was 2.5 days. All fractures were treated by a MIPO technique. A pre-contoured distal locking plate was used for the distal tibial reconstruction. Secondary surgical procedures e.g. 2nd look, delayed primary closure, or skin grafting were necessary in 3 cases. The fibula was plated in 60% of cases. Four patients developed wound infections requiring antibiotics, and all resolved. The commonest rehabilitation regime was 6 weeks non weight bearing in plaster. Mean time to union was 18 weeks. There were 3 cases of delayed union, requiring bone grafting. One patient required removal of the plate due to local irritation, and one required a broken screw to be removed. Mean range of movement was 10 degrees dorsiflexion, 30 plantarflexion. The mean normalised AAOS foot and ankle core score was 41 (SD +/− 8).

We conclude that MIPO fixation of distal tibial fractures is a safe and effective method of treatment. Functional outcome does not significantly differ from that of the general population.

Objective

To compare clinical parameters associated with medial parapatellar and midvastus approaches for total knee arthroplasty in the early post-operative period.

Introduction: Uncemented sockets have been used for revision with good results in the literature. Tantalum coated acetabular uncemented implant is the next generation implant. We used Tritanium (Stryker Corp. Kalamazoo, USA) for revision of acetabulum and present the early results.

Aim: To determine early results of porous tantalum coated modular acetabular cups in revision hip arthroplasty.

Patients and methods:41 acetabular revisions in 41 patients were performed using Tritanium acetabular uncemented sockets between March 2007 and March 2008. Posterior approach was used for all procedures. AAOS system for acetabular bone deficiency and Harris hip score for function was used for assessment.

Results: Mean age of the patients was 67 yrs (range 45–88). 95% of cups were fixed with screws for initial stability. AAOS classification showed there were 17 % Type 1, 49 % Type 2, 24% Type 3 and 5% Type 4 defects and 5 % had no defect. Bone graft was used to in 70% of patients, mostly autograft from the reamings. Mean Harris Hip Score improved from 68 pre-operatively to 84 at the last follow-up. Cup integration was seen in 93% patients. In two patients with pelvic discontinuity there was migration and in one loosening of the implant. One patient was treated for deep vein thrombosis and one patient for infection.

Conclusion: Early results of tantalum coated acetabular socket are encouraging, in providing adequate initial stabilisation for biologic fixation in segmental, cavitatory and combined defects. Facility to use locking screws in multiple directions may help in addressing pelvic discontinuity.

Introduction: Classification systems are useful in research and clinical practise as it provides a common mode of communication and evaluation. Tibial pilon injuries are a complex group of fractures, whose classification and radiological assessment in clinical practise remains undetermined.

Methods: 50 CT scans and radiographs of tibial pilon fractures were evaluated independently by 6 orthopaedic surgeons, comprising 3 consultants, 2 registrars and 1 research fellow. Fractures were classified according to ruedi allgower, AO, Topliss et al. Each surgeon was given a period of 48 hours to review copy of the original article as well as written and diagrammatic representations. Assessment was done on two occasions, 4 weeks apart. The kappa coefficient of agreement was calculated with SPSS to determine interobserver reliability and intraobserver reproducibility of the classification systems. The evaluator was blinded as to treatment and functional outcome. Each evaluator was also asked to decide upon the fracture management based on the classification types and was compared with the actual management.

Result: The interobserver agreement for ruedi allgower, Ao and Topliss et al., was fair, moderate and poor respectively. The intraobserver agreement for ruedi allgower, AO and Topliss et al., classifications was moderate at best. There was poor agreement amongst observers regarding definite management plan based on these classification systems.

Discussion: The interobserver agreement was directly proportional to the familiarity and inversely proportional to the specificity of the classification system. The intraobserver agreement improved with experience. CT scan helped in delineating the fracture segments accurately but did not significantly affect inter or intraob-server agreement.

Conclusion: Existing classification systems help in understanding the pathoanatomy of osseous part of tibial pilon fracture complex. However, Soft tissue injury forms an integral part of this complex. Without inclusion of soft tissue injury, these classification systems have limited role in definitive management.

Introduction: Periprosthetic infection with extensive bone loss is a complex situation. The appropriate management of large bone defects has not been established. Without reconstruction amputation/disarticulation is the likely outcome.

Aim: To Analyse preliminary results of direct exchange endoprosthetic reconstruction for periprosthetic knee infection associated with segmental bone defects.

Methods: Study of patients with periprosthetic knee infection and severe osteolysis treated by direct exchange tumour prostheses between June, 2005 and May, 2008 (4 - Distal femoral & 2 - Total femoral Replacements). Exclusion criteria included polymicrobial infection, resistant organisms, depressed immunity and poor peripheral perfusion. At each clinical visit they were monitored for clinical, microbiological, haematological and radiological evidence of infection. Community based antibiotic therapy was provided by specialist microbiologists. All patients were counselled and consented by the operating surgeon and specialist microbiologist prior to surgery.

Results: The mean age and follow up were 70.2 years and 30.5 months respectively. The most common infecting organism was Staphylococcus epidermidis (four), followed by Streptococcus species. Mean duration of antibiotics was 6 weeks intravenous(community based) and 8 weeks oral. 1 patient required intervention by plastic surgeons at index procedure. Radiographs showed no changes at final followup. One patient had superficial wound infection, which was successfully debrided. Knee range of movements averaged full extension to 95 degrees. The mean oxford knee scores pre and post operatively were 58 and 39.4 respectively.

Conclusion: Salvage direct exchange endoprosthetic reconstruction has provided effective pain relief, stability and improved mobility in our experience. Isolation of sensitive organism, specialist microbiologist input, availability of specialist physiotherapy and plastic surgery service, appropriate community care, good patient compliance and surgeon’s experience are key to success in these patients. Morbidity was significantly reduced due to early mobilisation.

Introduction: The commonest surgical approach for total knee arthroplasty is medial parapatellar approach. This involves splitting the quadriceps tendon, potentially destabilising the extensor mechanism. The midvastus approach involves splitting the vastus medialis muscle instead of entering the quadriceps tendon, therefore, minimising interruption of the extensor mechanism without compromising the exposure of the knee.

Objective: To compare clinical parameters associated with medial parapatellar and midvastus approaches for total knee arthroplasty in the early postoperative period.

Methods: and Results: We present a prospective observational study of 77 patients undergoing primary total knee arthroplasty using medial parapatellar or midvastus approach (37 midvastus approach, 40 medial parapatellar approach). Ethical approval was obtained for the study. The prosthetic design and physical intervention was standardised in all the patients. The Oxford Knee Score, pain scale, knee flexion, unassisted straight leg raise, standing and walking were compared at 3rd, 5th and 7th day postoperatively, then at 6 weeks and at 3 months. The patients and physiotherapist were blinded to the type of approach used. The average age was 67 years (range 42 to 88). There were 49 women and 39 men. The average hospital stay was 7 days (range 2 to 15). There was statistically significant difference in duration of hospital stay, unassisted straight leg raise and standing at 3 days (p=0.001) all in favour of midvastus approach. There was no statistically significant difference in Oxford Knee Scores, pain scale and range of motion. The average duration to achieving straight leg raise for the midvastus group was 5 days and for the medial parapatellar approach group was 8 days

Conclusion: The study shows that total knee arthroplasty performed through the midvastus approach resulted in less postoperative pain, earlier unassisted straight leg raise and ambulation, therefore, shorter hospital stay as compared to medial parapatellar approach. This may be of benefit to the patients due to less discomfort after surgery and to the healthcare system due to shorter hospital stay for patients.

Periprosthetic infection with extensive bone loss is a complex situation. The appropriate management of large bone defects has not been established. Without reconstruction amputation/disarticulation is the likely outcome.

Aim of the study was to Analyse preliminary results of direct exchange endoprosthetic reconstruction for periprosthetic infection associated with segmental bone defects.

Study of patients with periprosthetic infection and severe osteolysis treated by direct exchange tumour prostheses between June, 2005 and May, 2008 (4 – Distal femoral & 2 – Total femoral Replacements). Microbiological evidence of infection was confirmed with regular monitoring of radiograph, crp, esr and wcc. Community based antibiotic therapy was provided by infectious disease team based in our institution.

The mean age and follow up were 74.2 years and 26.5 months respectively. Mean duration of antibiotics was 6 weeks intravenous(community based) and 3.5 months oral. 1 patient required intervention by plastic surgeons at index procedure. Radiographs at 6, 12 & 24 months showed no changes from immediate post-op. CRP, ESR and WBC count were within normal limits at the end of antibiotic therapy. One patient required prolonged pain relief with poor mobility due to instability in the opposite knee. One patient had infection recurrence. Knee range of movements averaged full extension to 95 degrees. The mean oxford knee scores pre and post operatively were 58 and 39.4 respectively.

We conclude that salvage endoprosthetic reconstruction has provided effective pain relief, stability and improved mobility in our experience. It has provided an oppourtunity to avoid amputation. Multidisciplinary support from plastic surgeons and specialist microbiologists is essential.

Purpose: To compare clinical parameters associated with medial parapatellar and midvastus approaches for total knee arthroplasty in the early postoperative period.

Method: We present a prospective observational study of 77 patients undergoing primary total knee arthroplasty using medial parapatellar or midvastus approach (37 midvastus approach, 40 medial parapatellar approach). Ethical approval was obtained for the study. The prosthetic design and physical intervention was standardised in all the patients. The Oxford Knee Score, pain scale, knee flexion, unassisted straight leg raise, standing and walking were compared at 3rd, 5th and 7th day postoperatively, then at 6 weeks and at 3 months. The patients and physiotherapist were blinded to the type of approach used.

Results: The average age was 67 years (range 42 to 88). There were 49 women and 39 men. The average hospital stay was 7 days (range 2 to 15). There was statistically significant difference in duration of hospital stay, unassisted straight leg raise and standing at 3 days (p=0.001) all in favour of midvastus approach. There was no statistically significant difference in Oxford Knee Scores, pain scale and range of motion. The average duration to achieving straight leg raise for the midvastus group was 5 days and for the medial parapatellar approach group was 8 days.

Conclusion: The study shows that total knee arthroplasty performed through the midvastus approach resulted in less postoperative pain, earlier unassisted straight leg raise and ambulation, therefore, shorter hospital stay as compared to medial parapatellar approach. This may be of benefit to the patients due to less discomfort after surgery and to the healthcare system due to shorter hospital stay for patients.

Segmental bone defects with complex fractures or chronic infections comprise a very special subset of patients. Modular endoprosthetic reconstruction is an operative solution. Without reconstruction amputation/disarticulation is the likely outcome.

Aim of the study was to analyse preliminary results of modular endoprosthetic reconstruction in nonneoplastic limb salvage.

11 patients(9 – distal femoral replacement, 2 – total femoral replacement) underwent salvage reconstruction between January 2005 and March 2008 for chronic periprosthetic infections(6 – single stage revision; 2 – two stage revision) and complex periprosthetic fractures(3) with segmental bone defects. Microbiological and haematological evidence of infection was confirmed in the infection group and treated with concomitant community based antibiotic therapy as per guidance from specialist team.

The mean age and follow up were 74.2 years and 27.5 months respectively. No intraoperative complications identified. Average post operative mobilisation was with frame at 5 days, 2 sticks at 2 weeks. 1 patient required plastic surgical intervention at index operation. 1 patient had recurrence of infection.

Radiographs at 6, 12 & 24 months showed no changes from immediate post-op. Microbiological and haematological evidence of infection eradication was considered as successful treatment. Knee range of movements averaged full extension to 95 degrees. Oxford knee scores showed maximal improvement in the single stage revision group.

We conclude that salvage endoprosthetic reconstruction has provided an oppourtunity to avoid amputation. A significant improvement in overall range of motion, knee scores, pain relief and stability was achieved in this highly complex subset of patients. Multidisciplinary support from plastic surgeons and specialist microbiologists is essential.

Resurfacing arthroplasty is advantageous over conventional total hip arthroplasty in that femoral bone stock is preserved. However, there has been controversy over the preservation of acetabular bone stock in resurfacing arthroplasty, with the concern that it may result in excess reaming compared with total hip replacement. This is of concern as the prosthesis is primarily advocated in the young patient, who is likely to face future revision surgery.

We prospectively identified a cohort of 68 patients with primary hip osteoarthritis undergoing conventional total hip arthroplasty. During surgery, the excised femoral head and neck diameter was measured, along with the diameter of the final acetabular reamer used to achieve a bed of bleeding cancellous bone. The measured neck diameter was then used to calculate the minimum possible resurfacing head and cup sizes, with corresponding final reamer sizes that could have been used in each patient without neck notching for both Birmingham Hip Resurfacing (BHR, Smith & Nephew, 3rd Generation) and Articular Surface replacement (ASR, De Puy, 4th Generation). Reaming diameter and volume was compared for all 3 groups.

Mean reaming diameters for the THR, ASR and BHR groups were 51, 52 and 56mm respectively. Mean reaming volumes were 39, 40 and 47cc. There was a statistically significant difference between the THR and BHR groups for both reamed diameter and volume (p< 0.001). There was also a significant difference between the ASR and BHR groups for both reamed diameter and volume (p< 0.001). This difference was more pronounced with larger neck diameters.

Our data shows that the BHR results in more ace-tabular bone loss compared to total hip replacement. An implant with a lower profile acetabular cup and a larger variety of sizes such as the ASR may allow better preservation of acetabular bone stock.

Introduction: There is a recent trend of using a raft of small diameter 3.5 mm cortical screws instead of the large diameter 6.5mm screws in depressed tibial plateau fractures. Our aim was to compare the biomechanical properties of these two constructs in the normal and osteoporotic synthetic bone model.

Methods: 20 rigid polyurethane foam blocks with a density simulating osteoporotic bone and normal bone were obtained. A Schatzker type 3 fracture was created in each block. The fracture fragments were then elevated and supported using 2, 6.5mm cancellous screws or 4, 3.5mm cortical screws.

The fractures were loaded using a Lloyd’s machine and a load displacement curve was plotted.

Results: Osteoporotic model. The mean force needed to produce a depression of 5mm was 700.8N with the 4-screw construct and 512.4N with the 2 screw construct (p=0.007).

Non-osteoporotic model. The mean force requires to produce the same depression was 1878.2N with the 2-screw construct and 1938.2N with the 4 screw construct (p=0.42).

An increased fragmentation of the synthetic bone fragments was noticed with the 2-screw construct but not with the 4-screw construct.

Conclusion: A raft of 4, 3.5 mm cortical screws is biomechanically stronger than two, 6.5mm cancellous screws in resisting axial compression in osteoporotic bone.

To identify mechanisms of failure in plate and nail fixation in proximal humerus fractures. 5% of the proximal humerus fractures need surgical fixation, which is carried out, principally, by open reduction and internal fixation or closed reduction and intramedullary nailing. Fixation failure remains a problem. This study answers the mode of failure of these implants regardless of the fracture personality. In-vitro testing of proximal humerus fixation devices was undertaken in 30 simulated osteoporotic bone models. Fracture-line was created at the surgical neck of humerus in all samples and fixed with five fixation devices; three plating and two nailing devices. The samples were subjected to failure under compression and torque. Failure was achieved in all models. Three failure patterns were observed in torque testing:

The two conventional plates Cloverleaf and T-plate behaved similarly, failing due to screw pull-out from both the proximal and distal fragment with a deformed plate.

The failure mode is dependent on implant properties as well, independent of the fracture personality. It is important to recognise the potential points of failure (proximal or distal fragment) when making the choice of implant to avoid fixation failure.

Introduction: The commonest surgical approach for total knee arthroplasty is medial parapatellar approach. This involves splitting the quadriceps tendon, potentially destabilising the extensor mechanism. The midvastus approach involves splitting the vastus medialis muscle instead of entering the quadriceps tendon, therefore, minimising interruption of the extensor mechanism without compromising the exposure of the knee.

Objective: To compare clinical parameters associated with medial parapatellar and midvastus approaches for total knee arthroplasty in the early postoperative period.

Methods and results: We present a prospective observational study of 88 patients undergoing primary total knee arthroplasty using medial parapatellar or midvastus approach (44 in each group). The prosthetic design and physical intervention was standardised in all the patents. The Oxford Knee Score, pain scale, knee flexion, unassisted straight leg raise, standing and walking were compared at 3^rd, 5th and 7^th day postoperatively, then at 6 weeks and at 3 months. The patients and physiotherapist were blinded to the type of approach used. The average age was 67 years (range 42 to 88). There were 49 women and 39 men. The average hospital stay was 7 days (range 2 to 15). There was statistically significant difference in duration of hospital stay, unassisted straight leg raise and standing at 3 days (p=0.001) and pain scale at 5 days, all in favour of midvastus approach. There was no statistically significant difference in Oxford Knee Scores and duration to achieving full flexion and walking. The average duration to achieving straight leg raise for the midvastus group was 5 days and for the medial parapatellar approach group was 8 days

Conclusion: The study shows that total knee arthroplasty performed through the midvastus approach resulted in less postoperative pain, earlier unassisted straight leg raise and ambulation, therefore, shorter hospital stay as compared to medial parapatellar approach. This may be of benefit to the patients due to less discomfort after surgery, and to the healthcare system due to shorter hospital stay for patients.

Introduction and aims: There is a recent trend of using a raft of small diameter 3.5 mm cortical screws instead of the large diameter 6.5mm screws in depressed tibial plateau fractures (Schatzker type 3). Our aim was to compare the biomechanical properties of these two constructs in the normal and osteoporotic sawbone model.

Methods: 10 sawbone (solid rigid polyurethane foam) blocks with a density simulating that of an osteoporotic bone and 10 blocks of a density simulating normal bone were obtained. A Schatzker type 3 fracture was created in each block. The fracture fragments were then elevated and supported using 2, 6.5mm cancellous screws in 10 blocks and 4, 3.5mm cortical screws in the remaining.

The models were loaded to failure using a Lloyd’s machine. A displacement (depression) of 5mm was taken to be the point of failure. A load displacement curve was plotted using Nexygen software and the force needed to cause a depression of 5mm was calculated in each block. Mann Whitney U test was used for statistical analysis.

Results: Osteoporotic model

The mean force needed to produce a depression of 5mm was 700.8N with the 4-screw construct and 512.4N with the 2 screw construct. This difference was statistically significant (p=0.007).

Non-osteoporotic model

The mean force requires to produce the same depression was 1878.2N with the 2-screw construct and 1938.2N with the 4 screw construct. The difference was not statistically significant (p=0.42).

An increased fragmentation of the sawbone fragments was noticed with the 2-screw construct but not with the 4-screw construct.

Conclusion: A raft of 4, 3.5 mm cortical screws is biomechanically stronger than 2, 6.5mm cancellous screws in resisting axial compression in osteoporotic bone.

Purpose: To biomechanically compare the stability provided by 2, 6.5mm cancellous screws versus that provided by 4, 3.5mm cortical screws in depressed tibial plateau fractures

Methods: We obtained 20 sawbone(solid polyurethane foam) blocks of dimensions 9x6.5x3.5cm. 10 of these blocks had a density of normal cancellous bone (20pcf) and 10 represented osteoporotic bone (10pcf). We created a depressed fracture(Schatzker type 3) using a coring saw. Each fracture had 4 depressed fragments, which were elevated and supported using either 2,6.5mm cancellous screws or 4, 3.5mm cortical screws. The fractures were loaded axially using the Lloyds materials testing machine. A force displacement curve was plotted. A depression of 5mm was considered to be failure.

Results: Osteoporotic model|The mean force needed to produce a depression of 5mm was 700.8N with the 4-screw construct and 512.4N with the 2 screw construct. This difference was significantly significant (p=0.007). |Non-osteoporotic model|The mean force requires to produce the same depression was 1878.2N with the 2-screw construct and 1938.2N with the 4 screw construct. The difference was not statistically significant (p=0.42).

Conclusions: A raft of 4, 3.5 mm cortical screws was biomechanically stronger than 2, 6.5mm cancellous screws in resisting axial compression in the osteoporotic bone model. There was no significant difference in the 2 constructs in non-osteoporotic bone model.