Primary stability of a short bone-conserving femoral stem: a two-year randomized controlled trial using radiostereometric analysis.

Aims: The aim of this study was to determine the stability of a new short femoral stem compared with a conventional femoral stem in patients undergoing cementless total hip arthroplasty (THA), in a prospective randomized controlled trial using radiostereometric analysis (RSA). Patients and Methods: A total of 53 patients were randomized to receive cementless THA with either a short femoral stem (MiniHip, 26 patients, mean age: 52 years, nine male) or a conventional length femoral stem (MetaFix, 23 patients, mean age: 53 years, 11 male). All patients received the same cementless acetabular component. Two-year follow-up was available on 38 patients. Stability was assessed through migration and dynamically inducible micromotion. Radiographs for RSA were taken postoperatively and at three, six, 12, 18, and 24 months. Results: At two years, there was significantly less subsidence (inferior migration) of the short femoral stem (head, 0.26 mm, 95% confidence interval (CI) 0.08 to 0.43, sd 0.38; tip, 0.11 mm, 95% CI -0.08 to 0.31, sd 0.42) compared with the conventional stem (head, 0.62 mm, 95% CI 0.34 to 0.90, sd 0.56, p = 0.02; tip, 0.43 mm, 95% CI 0.21 to 0.65, sd 0.44, p = 0.03). There was no significant difference in dynamically inducible micromotion, rate of complications or functional outcome. Conclusion: This study demonstrates that the short femoral stem has a stable and predictable migration. However, longer-term survival analysis still needs to be determined. Cite this article: Bone Joint J 2018;100-B:1148-56.

Five-year outcome of proximal femoral endoprosthetic arthroplasty for non-tumour indications.

OBJECTIVES: A possible solution for the management of proximal femoral bone loss is a modular femoral endoprosthesis (EPR). Although the outcome of EPRs in tumour surgery has been well described, the outcome of their use in revision hip surgery has received less attention. The aim of this study was to describe the outcome of using EPR for non-neoplastic indications. METHODS: A retrospective review of 79 patients who underwent 80 EPRs for non-neoplastic indications was performed, including the rates of complication and survival and the mean Oxford Hip Scores (OHS), at a mean of five years post-operatively. The mean age at the time of surgery was 69 years (28 to 93) and the mean number of previous operations on the hip was 2.4 (0 to 17). The most common indications for EPR implantation were periprosthetic joint infection (PJI) (n = 40), periprosthetic fracture (n = 12) and failed osteosynthesis of a proximal femoral fracture or complex trauma (n = 11). RESULTS: Salvage was achieved in all patients. A total of 25 patients (25 EPRs, 31.6%) had a complication, the most common being infection (n = 9) and dislocation (n = 3). Further surgery was required for 18 EPRs (22%), nine of which were revision procedures. The five year survival of the EPR was 87% (95%CI: 76% to 98%). The mean OHS was 28 (4 to 48). Inferior survival and outcomes were seen in EPRs which were performed for the treatment of infection. However, the eradication of infection was achieved in 33 of the 40 (82.5%) which were undertaken for this indication. CONCLUSION: We recommend the continued use of proximal femoral EPRs for non-neoplastic indications, including PJI. Cite this article: Bone Joint J 2016;98-B:1463-70.

Intraosseous hibernoma: a rare adipocytic bone tumour.

Hibernoma is a benign adipose tumour that contains foetal brown fat cells. We report a case of hibernoma arising in the left ischium of a 65-year-old female with a past history of ovarian carcinoma. The patient presented with a relatively short history of left sacral/hip pain. Radiologically, the lesion, which was large (5 cm) and sclerotic, had been stable for a number of years. Histologically, it was composed mainly of plump cells with foamy, multivacuolated cytoplasm. These cells showed no reaction for epithelial, melanoma or leucocyte markers but expressed FABP4/aP2 and S100, indicating that they were brown fat cells. There was no mitotic activity or nuclear pleomorphism and the lesion was diagnosed as a benign intraosseous hibernoma (IOH). IOH is a recently identified benign adipocytic lesion that presents typically as a sclerotic bone lesion. It has characteristic morphological and immunophenotypic features and should be regarded as a discrete primary bone tumour that needs to be distinguished from metastatic carcinoma/melanoma, chondrosarcoma and metabolic storage diseases containing numerous foamy macrophages.

Primary synovial chondromatosis: a reassessment of malignant potential in 155 cases.

OBJECTIVE: Primary synovial chondromatosis (PSC) is a rare disorder characterised by cartilage formation in synovium-lined joints, tendon sheaths and bursae. It is thought that PSC cartilage arises from the proliferation of mesenchymal cells, which exhibit cartilaginous metaplasia in subintimal connective tissue. There are reports of transformation of PSC to chondrosarcoma, although the precise incidence and nature of this complication is uncertain. In this study we carried out a retrospective review PSC to determine the incidence of sarcomatous change in this condition, in addition to the clinical, radiological and pathological features that characterise this complication MATERIALS AND METHODS: We reviewed 155 cases of PSC and identified 4 cases (3 in the hip joint; 1 in the elbow joint) of aggressive behaviour and chondrosarcoma-like histology. RESULTS: Radiologically, these cases were all reported as showing features consistent with PSC and aggressive extra-articular soft tissue/bone involvement. Histologically, in addition to typical features of PSC, there was morphological evidence of peri-articular soft tissue and, in 2 cases, bone involvement by an infiltrating cartilaginous tumour. These tumours all behaved as locally aggressive neoplasms and did not give rise to metastasis. CONCLUSION: Our findings show that chondrosarcoma arises infrequently in PSC (approximately 2.5 %), and that this complication occurs most commonly in the hip joint (approximately 11 % of cases of hip PSC). These tumours behaved mainly as low-grade, locally aggressive tumours analogous to atypical cartilaginous tumour of bone/grade 1 chondrosarcoma of bone.

Intraosseous schwannoma in schwannomatosis.

This study investigates the clinical, radiological, and pathological features of two cases of intraosseous schwannoma that arose in patients with multiple soft tissue schwannomas. In both cases, the patients were adult females and the tibial bone was affected. Vestibular schwannomas were not identified, indicating that these were not cases of neurofibromatosis 2 (NF2). Radiographs showed a well-defined lytic lesion in the proximal tibia; in one case, this was associated with a pathological fracture. Histologically, both cases showed typical features of benign schwannoma. Molecular analysis of one of the excised tumors showed different alterations in the NF2 gene in keeping with a diagnosis of schwannomatosis. Our findings show for the first time that intraosseous schwannomas can occur in schwannomatosis.

Metastatic bone disease: Have we improved after a decade of guidelines?

OBJECTIVES: Guidelines for the management of patients with metastatic bone disease (MBD) have been available to the orthopaedic community for more than a decade, with little improvement in service provision to this increasingly large patient group. Improvements in adjuvant and neo-adjuvant treatments have increased both the number and overall survival of patients living with MBD. As a consequence the incidence of complications of MBD presenting to surgeons has increased and is set to increase further. The British Orthopaedic Oncology Society (BOOS) are to publish more revised detailed guidelines on what represents 'best practice' in managing patients with MBD. This article is designed to coincide with and publicise new BOOS guidelines and once again champion the cause of patients with MBD. METHODS: A series of short cases highlight common errors frequently being made in managing patients with MBD despite the availability of guidelines. RESULTS: Despite guidelines for the management of patients with MBD being available for more than a decade basic errors in management continue to be made, affecting patient survival and quality of life. CONCLUSIONS: It is hoped that by publicising the new BOOS guidelines the management of patients with MBD will improve over the next decade, significantly more than it has over the last decade.

The 2012 ABC orthopaedic fellowship in North America: May 24 to July 2.

In May 2012, in airports across the globe, seven orthopaedic surgeons bravely said goodbye to their loved ones, and slowly turned towards their respective aircraft. Filled with expectation and mild trepidation they stepped into the unknown… the ABC fellowship of 2012.

Optimal acetabular orientation for hip resurfacing.

Pseudotumours are a rare complication of hip resurfacing. They are thought to be a response to metal debris which may be caused by edge loading due to poor orientation of the acetabular component. Our aim was to determine the optimal acetabular orientation to minimise the risk of pseudotumour formation. We matched 31 hip resurfacings revised for pseudotumour formation with 58 controls who had a satisfactory outcome from this procedure. The radiographic inclination and anteversion angles of the acetabular component were measured on anteroposterior radiographs of the pelvis using Einzel-Bild-Roentgen-Analyse software. The mean inclination angle (47 degrees, 10 degrees to 81 degrees) and anteversion angle (14 degrees, 4 degrees to 34 degrees) of the pseudotumour cases were the same (p = 0.8, p = 0.2) as the controls, 46 degrees (29 degrees to 60 degrees) and 16 degrees (4 degrees to 30 degrees) respectively, but the variation was greater. Assuming an accuracy of implantation of +/- 10 degrees about a target position, the optimal radiographic position was found to be approximately 45 degrees of inclination and 20 degrees of anteversion. The incidence of pseudotumours inside the zone was four times lower (p = 0.007) than outside the zone. In order to minimise the risk of pseudotumour formation we recommend that surgeons implant the acetabular component at an inclination of 45 degrees (+/- 10) and anteversion of 20 degrees (+/- 10) on post-operative radiographs. Because of differences between the radiographic and the operative angles, this may be best achieved by aiming for an inclination of 40 degrees and an anteversion of 25 degrees.

The treatment of femoral neuropathy due to pseudotumour caused by metal-on-metal resurfacing arthroplasty.

Concerns now exist about the long-term biological effects of exposure to orthopaedic metal alloys, particularly serum cobalt and chromium ions derived from metal-on-metal wear debris in these patients. A pseudotumour mass complicating metal-on-metal resurfacing arthroplasty has been recognized by orthopaedic oncologists and specialist hip units. Pseudotumours may also present with a major nerve palsy. Two cases of femoral neuropathy due to pseudotumour masses caused by metal-on-metal resurfacing arthroplasty are presented. Preoperative neurophysiological studies showed severe and irreversible pathological changes to nerve function with neurohistopathological evidence of complete nerve destruction with a previously unreported pathological appearance. This may represent a previously unrecognized pathological process, possibly 'toxic' in nature, resulting from metal-on-metal wear debris. Prolonged follow-up and detailed clinical assessment of patients after hip resurfacing arthroplasty is advocated with planned and expeditious revision of any patient in whom evidence of femoral neuropathy develops.

Necrotic granulomatous pseudotumours in bilateral resurfacing hip arthoplasties: evidence for a type IV immune response.

Clinical, radiological and histological findings were analysed in four patients who developed bilateral pseudotumours following metal-on-metal (MoM) resurfacing arthroplasties of both hips. Using a panel of monoclonal antibodies directed against HLA-DR, macrophages (CD14, CD68), dendritic cells (DC-SIGN, S100, CD11c), B cells (CD20), and T cells (CD3, CD4, CD8), the nature of the heavy inflammatory response seen in these cases was examined. Bilateral masses developed in periprosthetic soft tissues following the second MoM arthroplasty; these were characterised histologically by extensive coagulative necrosis, a heavy macrophage infiltrate and the presence of granulomas containing macrophages and giant cells; there was also a diffuse lymphocyte and variable plasma cell and eosinophil polymorph infiltrate. Immunohistochemistry showed strong expression of HLA-DR, CD14 and CD68 in both granulomatous and necrotic areas; lymphocytes were predominantly CD3+/CD4+ T cells. The clinical, morphological and immunophenotypic features of these necrotic granulomatous pseudotumours, which in all cases develop following a second resurfacing hip arthroplasty, is suggestive of a type IV immune response, possibly to MoM metal alloy components.

Pseudotumours associated with metal-on-metal hip resurfacings.

We report 17 patients (20 hips) in whom metal-on-metal resurfacing had been performed and who presented with various symptoms and a soft-tissue mass which we termed a pseudotumour. Each patient underwent plain radiography and in some, CT, MRI and ultrasonography were also performed. In addition, histological examination of available samples was undertaken. All the patients were women and their presentation was variable. The most common symptom was discomfort in the region of the hip. Other symptoms included spontaneous dislocation, nerve palsy, a noticeable mass or a rash. The common histological features were extensive necrosis and lymphocytic infiltration. To date, 13 of the 20 hips have required revision to a conventional hip replacement. Two are awaiting revision. We estimate that approximately 1% of patients who have a metal-on-metal resurfacing develop a pseudotumour within five years. The cause is unknown and is probably multifactorial. There may be a toxic reaction to an excess of particulate metal wear debris or a hypersensitivity reaction to a normal amount of metal debris. We are concerned that with time the incidence of these pseudotumours may increase. Further investigation is required to define their cause.

Integrated hospital emergency care improves efficiency.

BACKGROUND: There is uncertainty about the most efficient model of emergency care. An attempt has been made to improve the process of emergency care in one hospital by developing an integrated model. METHODS: The medical admissions unit was relocated into the existing emergency department and came under the 4-hour target. Medical case records were redesigned to provide a common assessment document for all patients presenting as an emergency. Medical, surgical and paediatric short-stay wards were opened next to the emergency department. A clinical decision unit replaced the more traditional observation unit. The process of patient assessment was streamlined so that a patient requiring admission was fully clerked by the first attending doctor to a level suitable for registrar or consultant review. Patients were allocated directly to specialty on arrival. The effectiveness of this approach was measured with routine data over the same 3-month periods in 2005 and 2006. RESULTS: There was a 16.3% decrease in emergency medical admissions and a 3.9% decrease in emergency surgical admissions. The median length of stay for emergency medical patients was reduced from 7 to 5 days. The efficiency of the elective surgical services was also improved. Performance against the 4-hour target declined but was still acceptable. The number of bed days for admitted surgical and medical cases rose slightly. There was an increase in the number of medical outliers on surgical wards, a reduction in the number of incident forms and formal complaints and a reduction in income for the hospital. CONCLUSIONS: Integrated emergency care has the ability to use spare capacity within emergency care. It offers significant advantages beyond the emergency department. However, improved efficiency in processing emergency patients placed the hospital at a financial disadvantage.

The Trident constrained acetabular (bipolar) component for recurrent dislocation. New mode of liner failure.

Recurrent dislocation after reconstructive hip surgery remains a challenging problem to treat. Constrained acetabular components can provide an excellent solution, in selected patients. Failure of constrained components may still occur despite excellent component implantation and occurs at the liner-shell and shell-bone interfaces usually as a result of trauma or aseptic loosening. We describe the failure of a Trident bipolar acetabular component at its bipolar/insert interface, a previously unreported mode of failure.

Admission avoidance and early discharge of acute hospital admissions: an accident and emergency based scheme.

OBJECTIVES: To validate an accident and emergency (A&E) based approach to assisting early discharge or avoiding admission to acute hospital beds by means of two separate teams, one in hospital and the other in the community, working closely together at the interface between primary and secondary health care. DESIGN: A purpose designed admission avoidance (AA) team was established in the A&E department, and a target group of patients identified whose admissions might be avoided or curtailed. A rapid response community team (RRCT) based in Cambridge was also established to provide basic health care to patients in their homes after discharge from hospital. The key elements of the project were rapid assessment, careful selection of patients, early decision making at senior level, and close liaison with the community team. RESULTS: During the first year (1999) of the project the AA team assessed 785 patients and 257 patients were eventually discharged home to the care of the RRCT. Of these, 149 patients (58%) were comparable to a historical control group (from 1997/98), with regard to their demographic and clinical characteristics and care needs, and had an average length of hospital stay of 1.7 days compared with 6.3 days for the control group. The remaining 108 patients were not directly comparable but were supported by the teams because the benefits were clear and exclusion would have been unethical. These patients had an average length of stay of seven days. The readmission rate was 3 of 257(1.2%) for the intervention group and 8 of 531(1.5%) for the control group. A limited patient satisfaction survey among patients cared for at home revealed that 97% of patients were "satisfied to very satisfied" with the care provided. The RRCT had also looked after an additional 194 patients from other sources (total = 451), including postoperative orthopaedic early discharges from an adjacent hospital. The average length of care at home by the RRCT for all 451 patients was 6.6 days. The annual cost of the two teams was pound 113,900. CONCLUSIONS: These results indicate that an A&E based approach to the identification of patients suitable for short-term domiciliary support that aims rapidly to restore previous levels of independence, can reduce the burden of acute admissions to hospital without reducing quality of care or patient satisfaction. The scheme has now been established on a permanent basis and extension of this strategy to other patient groups is under evaluation.

The influence of density on frequency-dependent food selection: a comparison of four experiments with wild birds.

We compare the results of four experiments, conducted at different times and with different protocols, that explored the relationship between frequency-dependent selection and prey density in wild birds feeding on artificial populations of coloured baits. One (experiment 4) used pastry baits that differed only in the presence or absence of a red stripe, and this experiment provided no evidence for any kind of selective behaviour. The other three experiments used green and brown baits, and they all provided evidence for a trend towards increasing anti-apostatic selection with high densities (>100 baits m-2). However, one of these (experiment 3) provided no evidence for frequency-dependent selection at low densities (0.5-20 baits m-2), while the other two experiments concurred in suggesting a trend towards increasing apostatic selection with low densities (down to 2 baits m-2). Together, these experiments both support and qualify the published findings of experiment 1 that frequency- dependent selection by wild birds on bait populations is modified by density. Experiment 4 indicates that frequency-dependent selection may break down entirely if bait types are too similar, while experiment 3 indicates that some details of this trend with density will depend either on the protocol used or on exogenous changes in the birds' feeding behaviour.

Ipsilateral vascularised fibular transport for massive defects of the tibia.

The ipsilateral and contralateral fibulae have been used as a vascularised bone graft for loss of tibial bone usually by methods which have involved specialised microvascular techniques to preserve or re-establish the blood supply. We have developed a method of tibialisation of the fibula using the Ilizarov fixator system, ipsilateral vascularised fibular transport (IVFT), and have used it in five patients with massive loss of tibial bone after treatment of an open fracture, infected nonunion or chronic osteomyelitis. All had successful transport, proximal and distal union, and hypertrophy of the graft without fracture. One developed a squamous-cell carcinoma which ultimately required amputation of the limb. The advantage of IVFT is that the fibular segment retains its vascularity without the need for microvascular dissection or anastomoses. Superiosteal formation of new bone occurs if the tibial periosteal bed is retained. Other procedures such as corticotomy and lengthening can be carried out concurrently.

The significance of childhood sexual abuse for adult psychiatry.

Childhood sexual abuse is now recognized as a common occurrence, and it has been accepted that in a substantial number of cases victims suffer lasting psychological damage. Many such people are now speaking out and seeking help for the first time. They require sensitive assessment and understanding. Psychotherapy may well be helpful in appropriate cases, although studies of outcome are still lacking.

The use of psychotherapy with in-patients.

Some form of psychotherapy is now often attempted with psychiatric in-patients, even though most discussion of the subject is concerned with out-patients. This study looks at how a group of junior doctors used psychotherapy with 38 patients who were routinely admitted to an acute admission ward. Information was gathered from the doctors at the beginning of the treatment, during its course, and at the time the patient was discharged. Three distinct patterns emerged. One group of patients were seen as candidates for psychotherapy and definite progress seemed to be made. A second group were seen as candidates for psychotherapy but somehow no progress was made. A third group of patients were never seen as candidates for psychotherapy. These groups are looked at in some detail and the implications are discussed.