The normative Western Ontario Rotator Cuff Index values for age and sex

Abstract

The Western Ontario Rotator Cuff Index (WORC) is a widely used disease-specific outcome tool developed for patients with rotator cuff injuries. The determination of age- and sex-adjusted normative WORC values enables us to determine whether a procedure is more beneficial in specific patient groups because the results can be compared with a matched standard. The purpose of this study was to determine normative WORC values and assess whether the WORC needs an adjusted score for age and sex. We included participants using an online data-capturing program. We collected the following variables: age, sex, presence of shoulder pathology, Subjective Shoulder Value, and WORC score. We defined the mean normative WORC score per age category and analyzed sex differences in WORC scores per age category and in all domains of the WORC score. A total of 470 participants filled out the questionnaire. We excluded 44 participants because of pre-existing shoulder complaints or incomplete questionnaires. The mean total WORC score was 94% (standard deviation, 9%), and the mean total WORC score in every age and sex category was >90%. Of all participants, 85% scored between 91% and 100%; 63 participants (15%) scored 100%. The mean overall Subjective Shoulder Value was 98% (standard deviation, 6%). We found no statistically significant differences between sexes in the overall score, in the domain scores, and within the age categories. We defined normative values for the WORC questionnaire in a random prospective cohort and found no difference in scores between sexes. The mean normative scores all were within the variance of the maximum, and the WORC score did not deteriorate with age. It seems that the results of this subjective questionnaire change with the participant's perspective. An adjusted WORC score for age and sex is not necessary. This information can serve as a basis for comparison with patients with shoulder disease.