The purpose of this study was to evaluate the functional and oncological outcome of recycled autograft reconstruction after a wide excision for primary malignant bone tumor around the hip.

From 1998 to 2015, 67 patients with a primary malignant bone tumor involving proximal femur or periacetabular zone (P2) were included. There were 36 males and 31 females with a mean age of 34 years (13 to 58). Of these, 29 patients had grade I or II chondrosarcoma, 28 high-grade osteosarcoma, 6 Ewing's sarcoma and 4 undifferentiated pleomorphic sarcoma. Enneking stage of all 67 patients was stage II. Of the resection classification, proximal femur resection was performed in 29 patients, P1+P2 in 15, P2+P3 in 14, P1+P2+P3 in 4, P2 only in 4, and P2+proximal femur in 1. Extracorporeally irradiated recycled autograft and liquid nitrogen frozen autograft were performed in 44 and 23 patients, respectively.

At a mean follow-up of 98 months (10 to 239), 48 patients (72%) were continuously disease-free, 12 (18%) died of disease and 7 (10%) were alive with disease. The tumors of these patients who had died of disease were usually located in pelvic bones (10/12). Of these 37 patients with pelvic tumors, 7 patients (22%) had local recurrence, four of them received external hemipelvectomy. Other complications included hip dislocation in 2 patients, nerve injury in 2 and deep infection in 2. However, the above complications were rarely occurred in the patients with proximal femur reconstruction. The mean Musculoskeletal Tumor Society functional score were 77% (53 to 93).

Recycled autograft reconstruction for primary malignant bone tumor around the hip is a valid method with acceptable morbidity and a favorable functional outcome.

The use of routine sampling for histological analysis during revision hip replacement has been standard practice in our unit for many years. It is used to identify the presence of inflammatory processes that may represent peri-prosthetic infection. This study follows up on a smaller study in the same unit in 2019 where an initial 152 cases were scrutinised. In this follow up study we examined 1,361 consecutive patients over a 16-year period whom had undergone revision hip replacement in a tertiary orthopaedic centre for any reason excluding primary bone tumour or malignant metastasis. All patients had tissue sampling for histopathological analysis performed by consultant histopathologists with a specialist interest in musculoskeletal pathology. The presence of bacteria in greater than 50% of samples sent for microbiological analysis in each patient was used as the gold standard diagnostic comparator for infection. This was then compared with the histology report for each patient. After excluding 219 patients with incomplete data and 1 sample rejection, 1,141 cases were examined. Microbiology confirmed infection in 132 cases (prevalence of infection 11.04%) and histopathology analysis suggested infection in 171 cases. Only 64 cases with confirmed infection in more than 50% of microbiology samples had concurrent diagnosis of infection on histological analysis (5.60% of total; PPV 51.20%). Furthermore, microbiology analysis confirmed infection in 62 cases where histological analysis failed to identify infection (5.43% of total; False negative rate 49.21%). Overall, histopathology analysis was seen to have a good specificity of 93.99% but poor sensitivity of 50.79%. We believe that this is the largest series in the literature and is somewhat unique in that all histology analysis was performed by consultant histopathologists with specialist interest in musculoskeletal pathology. Based on the costs incurred by this additional investigation our experience does not support routine sampling for histological analysis in revision hip arthroplasty. This is a substantial paradigm shift from current practice among revision arthroplasty surgeons in the United Kingdom but would equate to a substantial cost saving

Aims

Reconstruction of the acetabulum after resection of a periacetabular malignancy is technically challenging and many different techniques have been used with varying success. Our aim was to prepare a systematic review of the literature dealing with these techniques in order to clarify the management, the rate of complications and the outcomes.

Metal-on-metal hip bearings are being implanted into younger patients. The consequence of elevated levels of potentially carcinogenic metal ions is therefore a cause for concern. We have determined the levels of cobalt (Co), chromium (Cr), titanium (Ti) and vanadium (Va) in the urine and whole blood of patients who had had metal-on-metal and metal-on-polyethylene articulations in situ for more than 30 years. We compared these with each other and with the levels for a control group of subjects.

We found significantly elevated levels of whole blood Ti, Va and urinary Cr in all arthroplasty groups. The whole blood and urine levels of Co were grossly elevated, by a factor of 50 and 300 times respectively in patients with loose metal-on-metal articulations when compared with the control group. Stable metal-on-metal articulations showed much lower levels. Elevated levels of whole blood or urinary Co may be useful in identifying metal-on-metal articulations which are loose.