Periprosthetic fractures after total hip arthroplasty are challenging, with potential difficulties associated not only with the fracture but also with implant loosening and bone loss. The incidence of periprosthetic fractures is gradually increasing. We undertook this study to evaluate the periprosthetic fractures presenting to our unit in terms of mechanism of failure, classification and treatment. Charts of patients with periprosthetic fractures presenting within the past six years were retrospectively analysed for demographic and injury details and corresponding radiographs were reviewed to classify the fracture and follow treatment. 45 fractures were identified, with an average age of 78.3 years. The male to female ratio was 5:4. Only 4 fractures occurred in revision prostheses. Two fractures were intraoperative.

The Vancouver system was used to classify the fractures, which can also form a basis for treatment. Three fractures of Vancouver type A were managed conservatively without complication. Thirteen fractures were Vancouver type B1, 12 of which underwent internal fixation, mostly plate osteosynthesis; two of these subsequently failed. Recent fractures have been stabilised using locking plates, with no recorded failures. Fifteen fractures were Vancouver type B2, 11 of which were greater than 5 years post arthroplasty. Most underwent revision of the femoral component. Five of these patients had reported pain for some time preceding fracture. Seven fractures were Vancouver type B3, all occurring greater than 7 years post arthroplasty. Most underwent femoral revision. Seven fractures were Vancouver type C, all underwent plate fixation without failure.

Although there is variability within the group studied, this series demonstrates gradual standardisation of treatment with use of locking plates and a preferred long revision femoral stem. The reports of pain preceding fracture in a proportion of the Vancouver B2 group prompts greater postoperative surveillance in patients with early signs of femoral loosening.

Introduction: Therapeutic bone marrow transplantation has increased survival in Hurler syndrome, but the effects on musculoskeletal development remain unclear. Long term reports on mobility are poor, with many patients gradually losing walking ability in later childhood secondary to hip subluxation and joint contractures. As previous cohorts are small, data is limited.

Methods: We detail the follow up of twenty patients over a mean of 94 months (range 1 – 17.4 years). Radiographs were assessed for hip dysplasia using acetabular angle of Sharp, centre edge angle of Wiberg and tibiofemoral shaft angle. Clinical examination was performed at an annual multidisciplinary assessment by one clinician and compared against age matched controls. 3D gait analysis was performed on eight older children, and deviance in kinematic variables was plotted against controls with Mann-Whitney U test for statistical analysis.

Results: All patients demonstrated characteristic ace-tabular dysplasia. Fourteen patients have undergone containment surgery at a mean of 4.4 years. Innominate osteotomy is an essential part of this. Mean preoperative acetabular angle was reduced from 34 ± 4° to 22 ± 3°. Femoral head containment is maintained, with mean centre edge angle in older patients 39 ± 7°. Genu valgum is observed early, and five patients underwent medial epiphyseal stapling at a mean of 7.8 years, decreasing tibiofemoral angle by a mean of 8.0°. All patients are currently independently mobile, with restriction of internal hip rotation being the only significant clinical finding (P< 0.001). Joint contractures were not noted. Walking speed and stride length were comparable to controls, but endurance is reduced by about one quarter. Gait analysis demonstrates a characteristic pattern, with anterior pelvic tilt secondary to thoracolumbar gibbus, relative hip flexion throughout the gait cycle, valgus knees and compensatory pronated feet; all measured deviations were significant (P< 0.001).

Conclusions This large group maintained successful hip containment and good mobility throughout childhood. Innominate osteotomy alone has been used recently. Despite plain film appearance, genu valgum is a functional problem in gait, and we would anticipate greater use of corrective stapling in the future. This is the first report of gait analysis in Hurler syndrome, and features specific to the condition are described.

This was a double-blind randomised controlled study. The objective of this study was to determine the cause of post-injection pain after peri-articular steroid injection. Approval for this study was granted by the hospital’s Ethics Committee. Selection criteria included all patients undergoing a peri-articular injection under the care of the senior author. Patients who elected to be in this study gave their consent following a detailed explanation of the study and provision of a patient information leaflet. The enrolled patients were randomised into one of two groups. Group A received a standard triamcinolone acetonide injection mixed with bupivicaine. Group B patients received triamcinolone acetonide without the preservative part of the drug and bupivicaine. Both the patient and the surgeon were unaware which group the patient was selected to be in. Patients’ scores were recorded using visual analogue scales and pain severity scores prior to injection and 4 days following injection. Inflammatory signs were also recorded at 4 days post-procedure. A total of 52 patients were enrolled. Pain scores reduced by 46% in group A and 43% in group B. Inflammatory signs occurred in 26% less cases when group B was compared with group A, however this was not statistically significant.

A review of the first two hundred and ten patients undergoing Birmingham hip re-surfacing between January 2003 and June 2005 was performed. All surgeries were performed by a single consultant orthopaedic surgeon. All resurfacings were carried out utilising the antero-lateral approach to the hip.

Mean review post-operatively was at six weeks. The following clinical parameters were evaluated: length of in-hospital patient stay, intra-operative blood loss and post-operative range of joint movement. In addition, the following radiological measurements were made: the acetabular inclination angle, the head-shaft angle and evidence of leg-length discrepancy.

One patient experienced fracture of the femoral neck and two other patients underwent revision surgery. Our results demonstrate that the anterolateral approach represents an alternative approach, with short-term results comaprible to the posterior approach for hip resurfacing.

The aim of this study is to evaluate the effectiveness of the application of vibration, during the femoral cementation, as a cementing technique.

It has been demonstrated that when vibration of a constant frequency was utilised, flow of low viscosity cement increased with vibration of increasing amplitude up to a particular acceleration. Above this acceleration there was little additional benefit. It has also been shown that when constant amplitude was used the flow increase was uniform over a wide frequency range, eventually falling off over a particular frequency. These results prove that the flow of orthopaedic bone cement is significantly affected by mechanical vibration of the receiving structure. It is our hypothesis that vibration promotes the ingress of bone cement into cancellous bone.

The effect of mechanical vibration in the frequency range 0–500 Hz on the cadaveric human femur has been assessed in the past. It was found that when the bone was fixed at both ends, its resonant frequency was markedly affected by end loading and damping. If the conditions of the experiment were designed to simulate the condition of the femur when prepared for a total hip replacement, it was found that the bone did not resonate but behaved in a mass-like mode. The significance of this observation is that in the event of vibration being applied to enhance the penetration of orthopaedic bone cement, the movement induced in the bone will be proportional to the force applied regardless of frequency.