Open synovectomy for treatment of tenosynovial giant cell tumors of the knee in children

We present seven pediatric cases of open knee synovectomy for tenosynovial giant cell tumor (TGCT)-four diffuse (D-TGCT) and three nodular (N-TGCT). The mean patient age at surgery was 11.3 ± 4.77 years. Five cases were diagnosed and treated within the past 2 years, indicating an unusually high incidence of TGCT in our institution. Subtotal synovectomy was performed through an anterior parapatellar approach, while posterior lesions were accessed between the semitendinosus and medial gastrocnemius muscles. The mean follow-up period was 39 ± 62.3 months (minimum 12 months). No recurrences were detected on follow-up MRI. Six patients regained full knee range of motion, and none exhibited postoperative monoarthritis. These favorable outcomes support open synovectomy as a safe and effective treatment for knee-localized D-TGCT and N-TGCT, especially in cases with posterior or retrocondylar localization.