Balancing Tumor Control and Cartilage Preservation for Patients with Giant Cell Tumor of Bone Around the Knee

When managing aggressive giant cell tumor of bone (GCTB) around the knee joint, surgeons are often caught in a dilemma when determining whether to perform marginal excision or intralesional curettage. The purpose of this study was to report the long-term results of different treatment strategies in our institute. We retrospectively reviewed 64 eligible cases (34 female and 30 male) with a GCTB (37 in the distal femur, 27 in the proximal tibia) treated from 2002 to 2013. Forty patients received intralesional curettage (group A). Twenty-four received marginal excision of the tumor, with 18 of them undergoing reconstruction with unicondylar osteoarticular allograft (UOA) (group B) and 6 receiving arthroplasty reconstruction (group C). The minimum follow-up was 8 years, and the oncological status, clinical outcomes, and cartilage condition were analyzed. Tumor recurrence was most common in group A (10 of 40, 25.0%), followed by group B (1 of 18, 5.6%) and group C (0 of 6). Eleven patients in group A (27.5%) and 6 in group B (33.3%) developed osteoarthritis (Kellgren-Lawrence grade 3 or 4). Five patients in group A (12.5%) and 3 patients in group B (16.7%) received total knee arthroplasty. Risk factors for the development of osteoarthritis in group A included a centrally located tumor, tumor length of >6 cm, a tumor-cartilage distance of ≤3 mm, and >50% subchondral bone involvement. In group B, osteoarthritis mostly resulted from postoperative complications. The mean Musculoskeletal Tumor Society (MSTS) score was 87.9 in group A, 84.8 in group B, and 93.3 in group C. Although intralesional curettage preserved cartilage and resulted in better function, it was associated with a higher tumor recurrence rate in our series. For advanced tumors close to the articular cartilage with significant subchondral bone involvement, marginal excision with UOA reconstruction might be a viable alternative. Arthroplasty should be reserved for patients who have bicondylar involvement with severe bone and cartilage loss making cartilage preservation impossible. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.