Total Synovectomy and Bone Grafting/Cementation after Curettage of the Bone Lesion in Diffuse Type of Tenosynovial Giant Cell Tumor: A Retrospective Cohort Study‎

Objectives: Although the diffuse type of tenosynovial giant cell tumor (D-TGCT) is rare, bone involvement is common in such lesions. However, the optimal management of bone lesions in D-TGCT is not well-described. In this study, we reported the outcomes of total synovectomy, curettage, and bone grafting/cementation in the treatment of D-TGCT with subchondral bone involvement. We also described the prevalence, demographic, and characteristic features of the lesions. Methods: In a retrospective study, we included 13 patients with D-TGCT of large joints and associated subchondral cyst/cyst-like bone lesions of ≥ 5 mm that were managed with total synovectomy and curettage. Cavities with a bone defect of ≤ 30 mm (n=12) were filled with bone grafts. Cavities of 30 mm (n=1) were augmented with bone cement. The limb function was evaluated by the Musculoskeletal Tumor Society (MSTS) score. Results: The study population consisted of 6 (46.1%) males and 7 (53.9%) females with a mean age of 30 ± 7.9 years. The most frequent sites of involvement were the knees and ankle joints (n=5 each, 38.5%). The mean follow-up of the patients was 69.2 ± 32.9 months. The mean MSTS score of the patients was obtained at 98.2 ± 3.2 (range 90-100). The D-TGCT recurred in two patients, both of which were in the synovium. Postoperative complications were three cases of transient pain and one case of knee joint stiffness. While no patient had an osteoarthritic change in preoperative radiographs, two patients had osteoarthritic change (grade II) in the last follow-up, one in the knee and one in the hip. Conclusion: Curettage and filling the defect with bone graft or cement are adequate treatments for managing bone lesions in D-TGCT.