Translation, cross-cultural adaption and validation of the German version of the Foot and Ankle Ability Measure for patients with chronic ankle instability

OBJECTIVES: The evaluation of health-related quality of life and physical function is important for determining therapeutic strategies following ankle injuries. The Anglo-American Foot and Ankle Ability Measure (FAAM) is a valid and reliable self-reported measure to detect functional deficits in chronic lateral ankle instability. The purpose of this study was to translate, cross-culturally adapt and validate the FAAM questionnaire for use with German-speaking patients with chronic lateral ankle instability. PATIENTS/PARTICIPANTS: Preoperative and conservatively treated patients with chronic lateral ankle instability. Sport students and volleyball athletes served as control groups. MAIN OUTCOME MEASUREMENTS: The FAAM was forward and back translated, cross-culturally adapted and validated. The study population completed the FAAM-G questionnaire twice within 3-5 days. Additionally, the patients were scored with the Good ankle laxity classification system. Test-Retest reliability, construct validity and internal consistency were calculated. RESULTS: Reliability and validity of the FAAM-G were examined in presurgical chronic ankle instability patients (n=24), conservatively treated chronic ankle instability patients (n=17), university sport students (n=31) and volleyballers (n=37). Test-retest reliability revealed fair, good, or excellent reliability (inter-class correlation coefficient (ICC)=0.590-0.998; ρ=0.528-1.000). Construct validity, tested between the FAAM-G subscores and the Good et al ankle laxity classification system demonstrated strong correlations (ρ = -0.819 to -0.861). CONCLUSIONS: The original FAAM questionnaire was successfully translated and cross-culturally adapted from English to German. Corresponding to the Anglo-American version, the FAAM-G is a reliable and valid questionnaire for self-reported assessment of pain and disability in German-speaking patients suffering from chronic ankle instability.