Have the difficulties and complications of surgical treatment for chondroblastoma of the adjoining knee joint been overestimated?

BACKGROUND AND OBJECTIVE: Chondroblastoma is difficult to treat as the tumor is surrounded by both articular cartilage and the epiphyseal plate. The differences in joint shape further complicate the problem. This retrospective study evaluates the efficacy of intraregional aggressive curettage and allogeneic bone grafting for treating chondroblastoma of the adjoining knee joint. METHODS: From February 2010 to February 2017, 36 patients with chondroblastoma of the adjoining knee joint were identified. All patients were treated with intraregional aggressive curettage, phenolization, and allogeneic bone grafting. Follow-up for lesion healing, local recurrence, functional outcomes and secondary osteoarthritis were assessed both clinically and radiologically. RESULTS: Thirty-six patients (mean age 17 years) were enrolled with a mean follow-up of 51.8 months (18–98 months). The tumor locations were as follows: distal femur (14), proximal tibia (20), and patella (2). Only 1 patient relapsed, 10 months post-operation. All patients had good bone healing. No knee varus or valgus deformity developed. The mean Musculoskeletal Tumor Society functional score was 28.6 ± 1.1 post-operation. At the last follow-up, secondary osteoarthritis was found in 1 patient, the patient was asymptomatic. CONCLUSIONS: Intraregional aggressive curettage, phenolization, and allogeneic bone grafting are effective for treatment of chondroblastoma of the adjoining knee joint.