Translation, cross-cultural adaptation and validation of the polish version of the Oxford Shoulder Score in patients undergoing arthroscopic rotator cuff repair

Background The Oxford Shoulder Score (OSS) is a simple and reliable, joint-specific, self-reported outcome measure. It can be applied in patients with shoulder disease other than instability. The purpose of this study was to perform a translation, cultural adaptation of the Polish version of the OSS and to evaluate its selected psychometric properties in patients after arthroscopic rotator cuff repair. Methods Sixty-nine subjects participated in the study, with a mean age 55.5 (ranging from 40 to 65 years). The OSS has been translated using the widely accepted guidelines. All patients completed the Polish version of OSS (OSS-PL), the short version of the Disabilities of Arm, Shoulder and Hand Questionnaire (QuickDASH), the Short Form-36 v. 2.0 (SF-36) and the 7-point Global Rating of Change Scale (GRC). Results High internal consistency of 0.96 was found using Cronbach's alpha coefficient. Reliability of the OSS resulted in Intraclass Correlation Coefficient (ICC) = 0.99, Standard Error of Measurement (SEM) = 1.14 and Minimal Detectable Change (MDC) = 3.15. The validity analysis showed a moderate (General health r = 0.34) to high (Physical role functioning r = 0.82) correlation between the OSS-PL and SF-36 and a high correlation between the OSS-PL and the QuickDASH (r = - 0.92). Conclusions The Polish version of OSS is a reliable and valid, self-reported questionnaire, which can be applied in patients with a rotator cuff tear undergoing reconstruction surgery. The very good psychometric properties of the Polish version of the OSS indicate that it can be used in clinical practice and scientific research.