Background

Endoprosthetic reconstruction is an established method of treatment for primary bone tumours in children. Traditionally these were implanted with cemented intramedullary fixation. Hydroxyapatite collars at the shoulder of the implant are now standard on all extremity endoprostheses, but older cases were implanted without collars. Uncemented intramedullary fixation with hydroxyapatite collars has also been used in an attempt to reduce the incidence of problems such as aseptic loosening. Currently there are various indications that dictate which method is used.

Autologous chondrocyte implantation (ACII) has been shown to have favourable results in the treatment of symptomatic chondral and osteochondral lesions. However, there are few reports on the outcomes of this technique in adolescents.

The aim was to assess functional outcome and pain relief in adolescents undergoing autologous chondrocyte implantation (ACI).

Thirty-one adolescent patients undergoing ACI or Matrix-assisted chondrocyte implantation (MACI) were identified from a larger prospective study. Mean age was 16.3 years (range 14 – 18) with a mean follow-up of 66.3 months (12–126 months).

There were 22 males and nine females. All patients were symptomatic; 30 had isolated lesions and one had multiple lesions. Patients were assessed pre and postoperatively using the Visual Analogue Score (VAS), the Stanmore/Bentley Functional Rating Score and the Modified Cincinnati Rating System.

The mean VAS improved from 5.8 pre-operatively to 2 post-operatively. The Stanmore/Bentley Functional Rating Score improved from 2.9 to 0.9 whilst the Modified Cincinnati Rating System improved from 49.8 pre-operatively to 81.3 postoperatively with 87% of patients achieving excellent or good results. All postoperative scores exhibited statistically significant improvement from pre-operative scores.

The results show that, in this particular group of patients, this procedure produces reduction in pain and a statistically significant improvement in function postoperatively. We strongly recommend this procedure in the management of adolescents with symptomatic chondral defects.

Introduction: The London Implant Retrieval Centre (LIRC) was founded to investigate the high incidence of unexplained failures of Metal-on-Metal (MoM) hips. A multidisciplinary team analyse the failed hips, investigations include CT and MRI scans, blood and synovial fluid tests, wear measurements, X-rays and clinical data from the explanting surgeons.

Wear measurements of 100 explanted hips have been carried out on a Taylor Hobson 365 Roundness Machine using the LIRC Wear Protocol. It was found that 50% of explanted cups were wearing less than 5 μm/year and 60% of components were wearing less than 10 μm/year. Wear tests on hip joint simulators predict wear rates between 2 and 8 μm/year. However, 6% of cups are wearing faster than 100 μm/year, with 16% of cups have wear patches deeper than 100 μm and that 4% have a wear patch deeper than 300 μm.

Discussion: This paper considers the common characteristics of components in this very high wearing category. Engineering parameters such as head/cup clearance, surface finish, form errors and head cup contact conditions are investigated. This is correlated with clinical data and other results from the LIRC.

Cup position is an important factor, all of the high wearing components are outside the Lewinick’s Box, however it is shown that mal position is does not always lead to extreme wear. Further analysis is taking place to calculate the size of the contact patch between head and cup (based on patient data and biomechanics) and the proximity of the contact patch to the edge of the cup.

Conclusion: The study of explanted components shows that 6% exhibit extreme wear, and although several “risk” factors can be identified, it is not clear why only a proportion of these components show extremely high wear rates. This is the subject of current investigation.

Introduction: Local problems of metal on metal (MOM) hip arthroplasty such as pseudotumours, neck thinning and osteolysis maybe related to concentrations of cobalt and chromium ions in the synovial fluid. There is little reported on these values. Our aim was to determine the range of metal ion levels in synovial fluid, and to investigate the relationship between these samples and simultaneous blood samples.

Methods: Synovial fluid and whole blood samples were taken from 30 consecutive patients at the time of revision surgery for a painful MOM hip. Aspirated fluid was not visibly contaminated with blood. Impants were in situ for a mean period of 31 months. All had normal renal function. Samples were analysed using ICP mass spectrometry and compared with 10 samples from patients without implants.

Results: The mean (and range) of synovial fluid metal ion levels were 1965 ug/l (30 to 13618) and 6265 ug/l (11 to 81630) for Cobalt and Chromium respectively. There was a good correlation between synovial and blood levels for both cobalt (R=0.65, p = 0.0001) and chromium (R = 0.59, p = 0.006).

Discussion and Conclusion: Metal ions in synovial fluid from MOM hips are generated from wear of the bearing surfaces, the correlation with blood metal ion levels, shown in this study, suggest that blood levels may be used as surrogate marker for hip wear rate. Our range of synovial fluid metal ion levels may be useful for those conducting in vitro studies on the biocompatibility of MOM hips.

Blood metal ions have been widely used to investigate metal-on-metal hip replacements, but their ability to discriminate between well-functioning and failed hips is not known. The Medicines and Healthcare products Regulatory Agency (MHRA) has suggested a cut-off level of 7 parts per billion (ppb).

We performed a pair-matched, case-control study to investigate the sensitivity and specificity of blood metal ion levels for diagnosing failure in 176 patients with a unilateral metal-on-metal hip replacement. We recruited 88 cases with a pre-revision, unexplained failed hip and an equal number of matching controls with a well-functioning hip. We investigated the 7 ppb cut-off level for the maximum of cobalt or chromium and determined optimal mathematical cut-off levels from receiver-operating characteristic curves.

The 7 ppb cut-off level for the maximum of cobalt or chromium had a specificity of 89% and sensitivity 52% for detecting a pre-operative unexplained failed metal on metal hip replacement. The optimal cut-off level for the maximum of cobalt or chromium was 4.97 ppb and had sensitivity 63% and specificity 86%.

Blood metal ions had good discriminant ability to separate failed from well-functioning hip replacements. The MHRA cut-off level of 7 ppb provides a specific test but has poor sensitivity.

High Tibial Osteotomy (HTO) is a recognised method of correction for knee joint malalignment and unicom-partmental osteoarthritis. Long-term results of this technique have been reported and are favourable. Good results have also been reported with Autologous Chondrocyte Implantation (ACI-C, MACI). Malalignment, if present, should be corrected when ACI is performed. Although results have been reported for either procedure separately, the outcomes of combined HTO-ACI remain unreported. The aim of this study was to evaluate functional outcome in patients undergoing combined HTO-ACI procedures.

Twenty three patients undergoing a combined ACI-HTO procedure were identified retrospectively from a larger trial of patients undergoing ACI for symptomatic chondral defects. The mean age of the patients was 36 (28 – 49). The mean follow-up was 54 months (12 – 108) and mean defect size was 689mm2 (range 350 – 1200). Nine patients had ACI-C and HTO, the remainder having MACI and HTO. Pre and post-operative assessment was carried out using the Visual Analogue Score (VAS), the Bentley Functional Rating Score and the Modified Cincinnati Rating System.

The Mean VAS score improved from 7.4 (4 – 10) pre-operatively to 2.9 (0 – 6) post-operatively at the latest follow-up (p< 0.0001). The Bentley Functional Rating Score improved from 2.9 (2 – 4) to 1.8 (0 – 4), which was statistically significant (p< 0.0001). The Modified Cincinnati Rating System improved from 35.2 (20 – 49) pre-operatively to 68.7 (46 – 85) post-operatively (p< 0.0001). Fourteen patients underwent biopsy of the graft site at a mean of 13.7 months: 21% of biopsies were hyaline-like cartilage, 36% were mixed hyaline/fibrocartilage, 29 % were fibrocartilage and 14% were fibrous tissue.

Combining high tibial osteotomy with autologous chondrocyte implantation is an effective method of decreasing pain and increasing function in the short term. Further evaluation of this procedure is required.

Introduction: Autologous Chondrocyte Implantation (ACI) is a treatment option for symptomatic, full-thickness chondral/osteochondral injuries. Goals of surgery and rehabilitation include replacement of damaged cartilage with hyaline/hyaline-like cartilage, leading eventually to improved level of function. Intermediate and long-term results are promising in terms of functional improvement.

Purpose: To explore the hypothesis that non-hyaline cartilage repair tissue is associated with worse functional outcome and to assess whether the quality of the repair tissue formed following ACI improves with time post-surgery.

Methods and Results: Two hundred and forty eight patients who underwent ACI at our institution were studied, having had post-implantation biopsies of the repair tissue. Mean timing of biopsy was 14.8 months (range 3–55). 59 biopsies showed hyaline tissue (24%), 67 mixed hyaline and fibrocartilage (27%), 113 biopsies were fibrocartilage only (46%) and 9 patients had a fibrous tissue biopsy result (9%). 126 patients (51%) had hyaline tissue in the regenerate and demonstrated a mean Modified Cincinnati Rating Score (MCRS) of 84 and a mean Lysholm Score of 88 at last follow-up (Group 1). 122 patients (49%) had no hyaline tissue in the regenerate and scored a mean MCRS of 71 and a mean Lysholm Score of 73 (Group 2). Both Groups 1 and 2 demonstrated a statistically significant improvement in functional outcome between pre and post-operative scores (p< 0.0001). There was significant difference in post-operative scores between Groups 1 and 2 suggesting that presence of hyaline tissue in the regenerate is associated with improved functional outcome (p< 0.05). Finally, our statistical analysis suggested that if time post-implantation doubles, then the likelihood of a favourable histological outcome increases significantly.

Conclusion: ACI forms a durable repair tissue that remodels and continues to improve in quality with time. Poor functional outcome may reflect the presence of a non-hyaline cartilage repair tissue.

Introduction: Autologous chondrocyte implantation (ACI) has been used to treat patella cartilage lesions but several studies have indicated poorer results compared to lesions on the femoral condyles. This paper investigates the effectiveness of two different methods of ACI; porcine-derived collagen membrane as a cover (ACI-C) and matrix-carried autologous chondrocyte implantation (MACI).

Methods: 124 patients (mean age 33.5) with symptomatic osteochondral lesions in the patella were selected to undergo either ACI (56 patients) or MACI (68 patients). 1 year following surgery patients underwent check arthroscopy to assess the graft. Functional assessment was performed pre-operatively, at 6 months and yearly by using the modified Cincinnati score (MCS).

Results: 37.5% of patients experienced good or excellent clinical results according to the MCS in the ACI group compared with 69.2% in the MACI group (p = 0.0011). The mean MCS improved from 43.7 pre-operatively to 49.8 2 years following surgery in the ACI group, whereas in the MACI group the improvement was from 44.6 to 60.6 (p=0.07). Arthroscopic assessment showed a good to excellent International Cartilage Repair Society score in 89.7% of ACI-C grafts and 69.6% of MACI grafts (p = 0.08). There was a higher re-operation rate (p = 0.044) in the ACI group (29%) compared with MACI (10%).

Conclusions: The results from this paper suggest that MACI is more successful in the treatment of patella cartilage lesions than ACI even though arthroscopic assessment showed the converse to be true. The higher complication and re-operation rate suggests that we should be treating such patients with MACI.

High tibial osteotomy (HTO) is a recognised method of correction for knee joint malalignment and unicompartmental osteoarthritis. The long term results of this technique have been reported and are favourable. Autologous chondrocyte implantation (ACI-C, MACI) has also been reported to have good results It is advised that malalignment, if present, should be corrected if ACI is to be performed. Although results have been reported for either procedure separately, the outcomes of combined HTO-ACI remain unreported.

To evaluate functional outcome in a group of patients undergoing combined HTO-ACI procedures.

Twenty three patients undergoing a combined ACI-HTO procedure were identified retrospectively from a larger trial of patients undergoing ACI for symptomatic chondral defects. The mean follow-up was 54 months (range 12 – 108) and the mean defect size was 689 mm2 (range 350 – 1200). Nine patients had ACI-C and HTO, the remainder having MACI and HTO. Pre and postoperative assessment was carried out using the Visual Analogue Score (VAS), the Bentley Functional Rating Score and the Modified Cincinnati Rating System.

The Mean VAS score improved from 7.4 pre-operatively to 2.9 post-operatively (p< 0.0001). The Bentley Functional Rating Score improved from 2.9 to 1.8 (p< 0.0001) whilst the Modified Cincinnati Rating System improved from 35.2 pre-operatively to 68.7 post-operatively (p< 0.0001). There was no significant difference between ACI-C and MACI. Two patients developed a non union at a mean of 13 months and a further two patients had a failure of the chondrocyte graft at a mean of 22.5 months.

Combining high tibial osteotomy with autologous chondrocyte implantation is an effective method of decreasing pain and increasing function at mean of 54 months follow-up. Further follow-up is required to assess the long term outcomes of these combined procedures.

Non-invasive expandable prostheses for limb salvage tumour surgery were first used in 2002. These implants allow ongoing lengthening of the operated limb to maintain limb-length equality and function while avoiding unnecessary repeat surgeries and the phenomenon of anniversary operations.

A large series of skeletally immature patients have been treated with these implants at the two leading orthopaedic oncology centres in England (Royal National Orthopaedic Hospital, Stanmore, and Royal Orthopaedic Hospital, Birmingham).

An up to date review of these patients has been made, documenting the relevant diagnoses, sites of tumour and types of implant used. 74 patients were assessed, with an age range of 7 – 16 years and follow up range of 4 – 88 months.

We identified five problems with lengthening. One was due to soft tissue restriction which resolved following excision of the hindering tissue. Another was due to autoclaving of the prosthesis prior to insertion and this patient, along with two others, all had successful further surgery to replace the gearbox. Another six patients required mechanism revision when the prosthesis had reached its maximal length. Complications included one fracture of the prosthesis that was revised successfully and six cases of metalwork infection (two of which were present prior to insertion of the implant and three of which were treated successfully with silver-coated implants). There were no cases of aseptic loosening.

Overall satisfaction was high with the patients avoiding operative lengthening and tolerating the non-invasive lengthenings well. Combined with satisfactory survivorship and functional outcome, we commend its use in the immature population of long bone tumour cases.

We measured the orientation of the acetabular and femoral components in 45 patients (33 men, 12 women) with a mean age of 53.4 years (30 to 74) who had undergone revision of metal-on-metal hip resurfacings. Three-dimensional CT was used to measure the inclination and version of the acetabular component, femoral version and the horizontal femoral offset, and the linear wear of the removed acetabular components was measured using a roundness machine.

We found that acetabular version and combined version of the acetabular and femoral components were weakly positively correlated with the rate of wear. The acetabular inclination angle was strongly positively correlated with the rate of wear. Femoral version was weakly negatively correlated with the rate of wear. Application of a threshold of > 5 μm/year for the rate of wear in order to separate the revisions into low or high wearing groups showed that more high wearing components were implanted outside Lewinnek’s safe zone, but that this was mainly due to the inclination of the acetabular component, which was the only parameter that significantly differed between the groups.

We were unable to show that excess version of the acetabular component alone or combined with femoral version was associated with an increase in the rate of wear based on our assessment of version using CT.

This study compared component wear rates and pre-revision blood metal ions levels in two groups of failed metal-on-metal hip arthroplasties: hip resurfacing and modular total hip replacement (THR).

There was no significant difference in the median rate of linear wear between the groups for both acetabular (p = 0.4633) and femoral (p = 0.0872) components. There was also no significant difference in the median linear wear rates when failed hip resurfacing and modular THR hips of the same type (ASR and Birmingham hip resurfacing (BHR)) were compared.

Unlike other studies of well-functioning hips, there was no significant difference in pre-revision blood metal ion levels between hip resurfacing and modular THR.

Edge loading was common in both groups, but more common in the resurfacing group (67%) than in the modular group (57%). However, this was not significant (p = 0.3479). We attribute this difference to retention of the neck in resurfacing of the hip, leading to impingement-type edge loading. This was supported by visual evidence of impingement on the femur.

These findings show that failed metal-on-metal hip resurfacing and modular THRs have similar component wear rates and are both associated with raised pre-revision blood levels of metal ions.

Between 1997 and 2007, 68 consecutive patients underwent replacement of the proximal humerus for tumour using a fixed-fulcrum massive endoprosthesis. Their mean age was 46 years (7 to 87). Ten patients were lost to follow-up and 16 patients died. The 42 surviving patients were assessed using the Musculoskeletal Tumor Society (MSTS) Score and the Toronto Extremity Salvage Score (TESS) at a mean follow-up of five years and 11 months (one year to ten years and nine months). The mean MSTS score was 72.3% (53.3% to 100%) and the mean TESS was 77.2% (58.6% to 100%).

Four of 42 patients received a new constrained humeral liner to reduce the risk of dislocation. This subgroup had a mean MSTS score of 77.7% and a mean TESS of 80.0%. The dislocation rate for the original prosthesis was 25.9; none of the patients with the new liner had a dislocation at a mean of 14.5 months (12 to 18).

Endoprosthetic replacement for tumours of the proximal humerus using this prosthesis is a reliable operation yielding good results without the documented problems of unconstrained prostheses. The performance of this prosthesis is expected to improve further with a new constrained humeral liner, which reduces the risk of dislocation.

Non-bacterial osteitis (NBO), a term referring to sterile bone lesions with non-specific histopathological features of inflammation, may be either uni- or multifocal, acute (6 months) or chronic, and recurrent. Only when the condition is chronic, recurrent and multifocal is it appropriate to use the term chronic recurrent multifocal osteomyelitis (CRMO).

We present our clinical experience as the largest reported series of children with NBO to date. Of 41 children (2–16 years) diagnosed with NBO in our institution over the last 6 years, 21 (51%) had recurrent disease and 18 of 41 (44%) had multifocal disease. The most common bones affected were the clavicle, femur and tibia (in order of decreasing prevalence) accounting for 44 (63%) of a total of 70 lesions. Only one individual had SAPHO syndrome and no other patients had evidence of bowel or skin disease. In the absence of evidence for an infective aetiology, we recommend non-steroidal anti-inflammatory agents as first line therapy, and bisphosphonates only in cases of resistant disease.

On the basis of our findings we propose a patient questionnaire and protocol for investigating and managing patients who present to orthopaedic surgeons with NBO. We predict that this will benefit patients with this disorder by providing valuable information about the pathogenesis, clinical outcome and response to treatment. In the future, clarification of the pathogenesis of this disease will undoubtedly help rationalise the therapeutic approach improving both quality of life and outcome for these patients.

Introduction: The Musculoskeletal Tumour Society recommends that patients with musculoskeletal tumours are treated in specialist centres. Core needle biopsy is an effective method of obtaining tissue diagnosis but a dilemma arises when the material is non-diagnostic. Our aim was to evaluate the management of non-diagnostic biopsies.

Method: We retrospectively reviewed all core needle biopsies performed between 2003 and 2009 in our regional centre. Non-diagnostic biopsies were identified and management reviewed.

Results: 4,520 core needle-biopsies were performed of which 120 (2.6%) were non-diagnostic. Of these 85 (70%) were treated definitively on the basis of existing imaging, 8 (7%) required further imaging before treatment and 27 (23%) had a repeat biopsy.

Of the 27 repeat biopsies a positive histological diagnosis was obtained in 22 patients. The remaining 5 were again non-diagnostic giving a total of 98 patients being treated definitively without a tissue diagnosis.

Of these 98 cases, 39 (40%) were treated non-operatively, 37 (38%) had curettage and 22 (22%) underwent wide excision.

In the curettage group 33 out of 37 patients had a benign tumour on final histology. Four patients turned out to have intermediate/high grade tumours and subsequently underwent wide excision.

In the wide excision group, 17 out of 22 patients had an intermediate/high grade tumour on final histology. Five patients underwent an unnecessarily wide excision of a benign lesion.

None of the patients treated non-operatively turned out to have a tumour.

Conclusion: After non-diagnostic core-needle biopsy, the patient can safely be managed without tissue diagnosis, with low error rate, provided they have been subjected to a multidisciplinary discussion.

Introduction: The aim of the study was to review the long-term survival and outcome of 49 consecutive endoprosthetic lower limb diaphyseal replacements undertaken for neoplastic conditions.

Methods: A retrospective review of all femoral and tibial diaphyseal replacements performed between 1990 and 2009 at our specialist bone and soft tissue tumour unit was performed. Minimum follow-up was one year. Joint sparing prostheses were excluded.

Results: 49 femoral (31) and tibial (18) diaphyseal replacements were implanted into 46 patients (31 male, 15 female). Mean age at surgery was 47 years (range 9–79). Surgery was performed for malignancy in 46 cases (97%), of which 41 (89%) were primary bone and soft tissue sarcomas. The predominant pathologies were osteosarcoma (24%), malignant fibrous histiocytoma (14%) and chondrosarcoma (14%). Mean follow-up was 81 months (range 12–221 months). Survival within the follow-up group was 96% at 1 year, 79% at 5 years, and 69% at 10 years. In surviving patients, using revision, recurrence and amputation as endpoints, prosthesis survival was 91% at 1 year, 58% at 5 years, and 33% at 10 years. In total, 13 prostheses underwent revision surgery and there were 3 amputations following diaphyseal replacement. Of these 16 cases, 75% were for aseptic loosening or prosthetic failure, 13% for tumour recurrence, and 13% for infection.

Discussion: Lower limb diaphyseal endoprosthetic replacements are a useful surgical treatment method for patients with malignant neoplastic diaphyseal bone lesions requiring excision and reconstruction. This is both limb salvage and joint-sparing reconstructive surgery.

Objectives:

To determine the diagnostic performance of image-guided percutaneous core needle biopsy (CNB) in patients presenting with pathologic fractures of the appendicular skeleton.

A retrospective audit identified 129 consecutive patients presenting with pathological fractures to a specialist orthopaedic oncology unit over a 9 year period. All patients underwent percutaneous CNB using CT (n=98), fluoroscopy (n=15) or US (n=16) guidance. In all cases MRI or CT was available prior to biopsy to assess the presence and degree of extra-osseous tumour mass. The resulting sample was classified as diagnostic (Group 1) or non-diagnostic (Group 2) on histopathological study. Diagnostic performance was evaluated on the basis of the diagnostic yield and accuracy; these were related to the site of the lesion and presence/absence of extra-osseous mass.

Of 129 biopsies, 99 (77%) were classified as Group 1 and 30 (23%) as Group 2. The commonest sites of pathological fracture without associated soft tissue component and resulting in a non-diagnostic biopsy were the proximal femur and proximal humerus. The average cross-sectional diameter of lesions in Group 1 was 5.7 x 5.9cm. Of the 30 lesions comprising Group 2, no soft tissue component was identified on pre-biopsy cross-sectional imaging in 27 lesions (90%) whereas the remaining 3 (10%) showed a smaller extra-osseous soft tissue component compared to the lesions in Group 1.

Image-guided percutaneous CNB is a reliable method for obtaining a tissue diagnosis in patients presenting with a pathologic fracture of the appendicular skeleton with high accuracy rate. However, those lesions which are purely intra-osseous or have only very small extra-osseous components are likely to be associated with a non-diagnostic biopsy, and should be considered for a primary open procedure.

Disarticulation of the hip in patients with high-grade tumours in the upper thigh results in significant morbidity. In patients with no disease of the proximal soft tissue a femoral stump may be preserved, leaving a fulcrum for movement and weight-bearing. We reviewed nine patients in whom the oncological decision would normally be to disarticulate, but who were treated by implantation of an endoprosthesis in order to create a functioning femoral stump. The surgery was undertaken for chondrosarcoma in four patients, pleomorphic sarcoma in three, osteosarcoma in one and fibrous dysplasia in one. At follow-up at a mean of 80 months (34 to 132), seven patients were alive and free from disease, one had died from lung metastases and another from a myocardial infarction. The mean functional outcome assessment was 50 (musculoskeletal tumor society), 50 and 60 (physical and mental Short-form 36 scores).

Implantation of an endoprosthesis into the stump in carefully selected patients allows fitting of an above-knee prosthesis and improves wellbeing and the functional outcome.

Elastofibroma dorsi is a rare, benign, slow-growing ‘pseudotumour’ classically presenting as an ill defined mass at the inferior pole of the scapula. Typical symptoms include mass, pain, scapular snapping and impingement like features. There is a predilection for females after the fifth decade of life. The aetiology is unclear.

We identified 15 patients (21 tumours) with a diagnosis of elastofibroma. Seven lesions were found on the left side and fourteen on the right; bilateral lesions were found in six patients. The male:female ratio was eight:seven and mean age at presentation was 60.9 years (range 40 – 71). The mean duration of symptoms (most commonly pain, mass and scapular snapping) prior to presentation was 25.8 months. Eighteen tumours were excised with a mean follow-up of 4.2 years (0.25–16). Four lesions were diagnosed by combined MRI and CT guided biopsy, the remainder identified using MRI alone. All patients were asked specifically about symptoms, occupation, family history and employment history (including hobbies). Pain was assessed using the Visual Analogue Score (VAS) and functional outcome using the Stanmore Percentage of Normal Shoulder Assessment (SPONSA) Score. Range of forward flexion of the shoulder joint was also assessed.

In the operative group, the mean VAS score improved from 4.6 (0–10) pre-operatively to 2.5 (0–8) post-operatively. Mean SPONSA scores improved from 61.5% (20 – 100) to 81.8% (30 – 100). Mean pre-operative forward flexion was 135 degrees (70 – 180), this improved to 166 degrees (100 – 180) post-operatively. A high number of patients had been involved in occupations involving heavy lifting. MRI had a 100% sensitivity in identifying elastofibroma when correlated with histopathological evaluation.

This series demonstrates that elastofibroma may be reliably diagnosed using MRI alone and, in the symptomatic patient, pain and function may be improved through operative excision.

Background: There is no consensus on the most appropriate prosthesis for treating osteoarthritis (OA) of the hip in young, highly active patients. Modern hip resurfacing is bone conserving, more stable and theoretically easier to revise than total hip arthroplasty. Early results of metal on metal resurfacing have been promising. We have compared two well matched cohorts of patients with regard to function, pain relief and patient satisfaction.

Methods: This prospective study included 2 cohorts of well matched patients treated with hip resurfacing (137 patients, 141 hips) and custom uncemented (CADCAM) stems (134 patients, 141 hips). All procedures were performed by a single surgeon. Outcome measures included Oxford, WOMAC and Harris hip scores. Statistical analysis was performed using the unpaired student’s t- test.

Results: One hundred and thirty four and 137 patients were included in the hip replacement and resurfacing groups respectively. The mean age of these patients was 54.6 years. The mean duration of follow up for the resurfacing group was 19.2 months compared to 13.4 months for the replacement group.

Pre operative oxford, Harris and WOMAC scores in the THA group were 41.1, 46.4 and 50.9 respectively while the post operative scores were 14.8, 95.8 and 5.0. In the HR group, pre- operative scores were 37.0, 54.1 and 45.9 respectively compared to 15.0, 96.8 and 6.1 post operatively. The degree of improvement was similar in both groups.

Conclusion: There was no significant difference in short term outcome between the groups of patients treated with hip resurfacing and total hip arthroplasty in the short term.