The Stanmore knee arthrodesis prosthesis.

Knee arthrodesis is most commonly performed for failed total knee arthroplasty. Conventional arthrodesis techniques are associated with a high incidence of complications and are unsuitable in cases with extensive bone loss. We report our medium-term results using a custom-made cemented knee arthrodesis prosthesis in 10 patients with a mean follow-up of 56.4 months (range, 15-199 months). The prosthesis was implanted as a 1- or 2-stage procedure for infected revision knee arthroplasty or tumor endoprosthesis in 9 patients and as a primary procedure in 1 patient with angiosarcoma involving the knee extensor mechanism. The average combined femoral and tibial bone deficit was 170 mm (range, 56-220 mm). Implant survivorship was 90%. All patients with retained prosthesis had no evidence of residual infection or loosening and were able to mobilize independently. One prosthesis was revised though retained following a prosthetic fracture, and 1 patient underwent above-knee amputation for uncontrolled infection. We conclude that the Stanmore knee arthrodesis prosthesis provides reliable fusion in an otherwise difficult-to-treat group of patients.

Long-term results of autologous chondrocyte implantation in the knee for chronic chondral and osteochondral defects.

BACKGROUND: Autologous chondrocyte implantation (ACI) has been shown to be effective in the midterm for the treatment of symptomatic articular cartilage lesions of the knee, but few long-term series have been published. The multioperated chronic articular cartilage defect remains a difficult condition to treat. PURPOSE: To examine the long-term clinical results of ACI for large chronic articular cartilage defects, many treated as salvage. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This is a prospective case series of 104 patients with a mean age of 30.2 years and a symptomatic lesion of the articular cartilage in the knee, who underwent ACI between 1998 and 2001. The mean duration of symptoms before surgery was 7.8 years. The mean number of previous surgical procedures on the cartilage defect, excluding arthroscopic debridement, was 1.3. The defects were large, with a mean size of 477.1 mm(2) (range, 120-2500 mm(2)). The modified Cincinnati, Stanmore/Bentley, and visual analog scale for pain scoring systems were used to assess pain and functional outcomes at a minimum 10 years (mean, 10.4 years; range, 10-12 years). RESULTS: Twenty-seven patients (26%) experienced graft failure at a mean of 5.7 years after ACI. Of the 73 patients who did not fail, 46 patients (63% of patients with a surviving graft) had an excellent result, 18 (25%) were good, 6 (8%) were fair, and 3 (4%) had a poor result. Of a total of 100 patients successfully followed up, 98 were satisfied with the ACI technique for their chronic knee pain and would undergo the procedure again. CONCLUSION: Autologous chondrocyte implantation can provide a long-term solution in more than 70% of young patients of a difficult-to-treat group with large chronic articular cartilage lesions, even in the salvage situation.

Combined autologous chondrocyte implantation (ACI) with supra-condylar femoral varus osteotomy, following lateral growth-plate damage in an adolescent knee: 8-year follow-up.

We report the 8-year clinical and radiographic outcome of an adolescent patient with a large osteochondral defect of the lateral femoral condyle, and ipsilateral genu valgum secondary to an epiphyseal injury, managed with autologous chondrocyte implantation (ACI) and supracondylar re-alignment femoral osteotomy. Long-term clinical success was achieved using this method, illustrating the effective use of re-alignment osteotomy in correcting mal-alignment of the knee, protecting the ACI graft site and providing the optimum environment for cartilage repair and regeneration. This is the first report of the combined use of ACI and femoral osteotomy for such a case.

Use of irradiated autologous bone in joint sparing endoprosthetic femoral replacement tumor surgery.

BACKGROUND: Joint preservation is usually attempted in cases of bone tumors, though insufficient bone following tumour resection may prevent fixation of conventional joint sparing prosthesis. To preserve the hip joint in skeletally immature patients, we have combined autologous proximal femoral irradiation and intercalary re-implantation with custom made distal femoral replacements. MATERIALS AND METHODS: A retrospective cohort study of four patients (aged 4-12 years); in whom irradiated autologous bone was combined with an extendable distal femoral endoprostheses was performed. There were three cases of osteosarcoma and one case of Ewing's sarcoma. RESULTS: At a mean follow-up of 70.5 months (range 26-185 months), all four patients were alive without evidence of local recurrence. There was no evidence of metastatic disease in three patients while one patient showed chest metastatic disease at presentation. In all cases, the irradiated segment of bone united with the proximal femur and demonstrated bone ongrowth at the prosthetic collar. There were no cases of loosening or peri-prosthetic fracture. One implant was revised after 14 years following fracture of the extending component of the endoprosthesis. CONCLUSIONS: We report encouraging results utilizing irradiated autologous proximal femoral bone combined with distal femoral replacement in skeletally immature patients.