Background. Tenosynovial giant cell tumour (TGCT) is a benign proliferative disease affecting synovial membranes. There are two forms, localised and diffuse, which although histologically similar are managed differently. It is locally invasive and is treated in most cases by operative excision. The aim of this study was to assess outcomes from the largest single-centre experience to date in patients with this condition. Methods. A retrospective analysis of 123 cases was performed in patients treated between 2003 and 2019 with TGCT of the foot and/or ankle. Data was collected on age at presentation, radiological pattern of disease, location of disease, treatment provided and recurrence rates. The minimum follow-up was 2 years with a mean of 7.7 years. Results. 47 male and 76 female patients with a mean age at diagnosis of 39 (range, 11–76) years were identified. 85 (69.1%) cases were categorised as localised and 38 (30.9%) were diffuse. Half of the cases presented in the ankle (62/123, 50.4%). 89% (110) of patients underwent open operative excision of the lesion. Radiotherapy was used in 2 cases for recurrent disease. Pain was the most common postoperative symptom which developed in 20% (22/110) of cases). 13 cases were managed nonoperatively where symptoms were minimal, with one case requiring surgery at a later date. Disease recurrence was 3.5% (3/85) in localised disease and 36.8% (14/38) in diffuse disease giving an overall recurrence rate of 13.8% (17/123). Conclusion. The outcomes of TGCT management are dependent on the type of disease, the extent of preoperative erosive changes and the presence of pre-operative pain. We present a summary of recommended management based on the experience from this single tertiary centre

Pigmented villonodular synovitis (PVNS) is a rare benign disease of the synovium of joints and tendon sheaths, which may be locally aggressive. We present 18 patients with diffuse-type PVNS of the foot and ankle followed for a mean of 5.1 years (2 to 11.8). There were seven men and 11 women, with a mean age of 42 years (18 to 73). A total of 13 patients underwent open or arthroscopic synovectomy, without post-operative radiotherapy. One had surgery at the referring unit before presentation with residual tibiotalar PVNS. The four patients who were managed non-operatively remain symptomatically controlled and under clinical and radiological surveillance. At final follow-up the mean Musculoskeletal Tumour Society score was 93.8% (95% confidence interval (CI) 85 to 100), the mean Toronto Extremity Salvage Score was 92 (95% CI 82 to 100) and the mean American Academy of Orthopaedic Surgeons foot and ankle score was 89 (95% CI 79 to 100). The lesion in the patient with residual PVNS resolved radiologically without further intervention six years after surgery. Targeted synovectomy without adjuvant radiotherapy can result in excellent outcomes, without recurrence. Asymptomatic patients can be successfully managed non-operatively. This is the first series to report clinical outcome scores for patients with diffuse-type PVNS of the foot and ankle. Cite this article: Bone Joint J 2013;95-B:384–90