Cross-cultural adaptation and validation of the Japanese version of the Toronto Extremity Salvage Score (TESS) for patients with malignant musculoskeletal tumors in the upper extremities

Background The Toronto Extremity Salvage Score (TESS) is a widely used disease-specific patient-completed questionnaire for the assessment of physical function in patients with musculoskeletal tumors ; however, there had not been the validated Japanese version of the TESS. The aim of this study was to validate the Japanese version of the TESS in patients with musculoskeletal tumors in the upper extremity. Methods After developing a Japanese version of the TESS, the questionnaire was administered to 53 patients to examine its reliability and validity in comparison with the Musculoskeletal Tumor Society (MSTS) scoring system and Short Form-36 (SF-36). Results Test–retest reliability with intraclass correlation coefficient (0.93) and internal consistency with Cronbach's alpha (0.90) were excellent. Factor analysis showed that the construct structure consisted of 3-item clusters, and the Akaike Information Criterion network also demonstrated that the items could be divided into 3 domains according to their content. The TESS strongly correlated with the MSTS rating scale (r = 0.750; P < 0.001) and the SF-36 physical functioning scale (r = 0.684; P < 0.001). However, as expected, the TESS had low correlations with the SF-36 mental health and role-emotional subscales and the MSTS scoring system manual dexterity domain. Conclusions Our study suggests that the TESS is a reliable and valid instrument to measure patient-reported physical functioning in patients with upper extremity sarcoma.