A cross-cultural adaptation and validation of the Chinese version of American orthopaedic foot and ankle society hallux metatarsophalangeal-interphalangeal scale (AOFAS-Hallux-MTP-IP) in patients with hallux valgus.

Abstract

Hallux valgus (HV) is a common deformity of the hallux, which affects the functional ability of patients and reduces their quality of life. The American Orthopaedic Foot and Ankle Society (AOFAS) Hallux Metatarsophalangeal (MTP)-Interphalangeal (IP) scale is a questionnaire widely used to comprehensively assess the condition of hallux deformities. The purpose of this study was to translate the AOFAS-MTP-IP scale into a Chinese version (AOFAS-MTP-IP-CV), conduct cross-cultural adaptation, and simultaneously evaluate its validity and reliability. Translate the AOFAS-Hallux-MTP-IP-CV according to general guidelines and conduct cross-cultural adaptation for it. From November 2024 to June 2025, a total of 120 patients with HV deformity who could communicate in Chinese were included. They successfully completed the demographic questionnaire, the Manchester-Oxford Foot Questionnaire-Chinese version (MOXFQ-CV), and the EuroQoL Group's five‑dimension questionnaire (EQ‑5D). The reliability of AOFAS-Hallux-MTP-IP-CV was determined by internal consistency, inter-rater reliability, intra-rater reliability, and test-retest reliability. Two orthopedic surgeons were responsible for the collection of questionnaires. The intra-rater reliability and inter-rater reliability were evaluated by the intraclass correlation coefficient (ICC). The internal consistency of the scale items was assessed by calculating the Cronbach's alpha coefficient. The Bland-Altman analysis was used to test the consistency between test-retest assessments. The construct validity of AOFAS-Hallux-MTP-IP-CV was determined by MOXFQ-CV and EQ-5D. Floor/ceiling effects were analyzed to assess scale responsiveness, with < 15% of scores at floor/ceiling levels indicating adequate range. The AOFAS-Hallux-MTP-IP-CV was well accepted with no ceiling or floor effect. The intra-rater reliabilities of the total score of the AOFAS-Hallux-MTP-IP-CV and the pain, function, and alignment dimensions were 0.941, 0.925, 0.945, and 0.922, respectively. The inter-rater reliabilities were 0.916, 0.877, 0.885, and 0.896, respectively. The Bland-Altman plots showed good consistency in test-retest measurements. The total score of AOFAS-Hallux-MTP-IP-CV showed moderate to strong correlations with the pain dimension (r = -0.676) and the walking/standing dimension (r = -0.757) of the MOXFQ and the EQ-5D (r = -0.601). The AOFAS-Hallux-MTP-IP-CV has good feasibility, reliability and validity. It can be recommended for the comprehensive assessment of the clinical conditions of patients with hallux valgus (HV) deformity in Mainland China.