Validation of a functional evaluation system in patients with musculoskeletal tumors.

The validity and reliability of the Musculoskeletal Tumor Society functional evaluation system were evaluated using the Nottingham Health Profile, the Short Form-36, and the EuroQol protocol to measure the quality of life of patients with malignant musculoskeletal tumors. Forty-nine patients were assessed and osteosarcoma around the knee was the most common type of tumor. Prosthetic reconstructions had been done in 55.1% of patients. In a content validity analysis, neither social nor psychologic domain was identified in the Musculoskeletal Tumor Society system. All items of the lower extremity were related to the same function-walking ability. The Musculoskeletal Tumor Society system had a strong correlation with other quality of life measures in the construct validity and the reliability, but each domain of the system was so comprehensive that it could not represent the quality of life properly. Furthermore, the preoperative and postoperative status of patients could not be compared using this system. The overall validity and reliability of the Musculoskeletal Tumor Society system seemed to be acceptable. However, this system may require additional development of the appropriate domains for evaluating the quality of life in patients with musculoskeletal tumors.