Asymptomatic rotator cuff tears: Patient demographics and baseline shoulder function

Background: The purpose of this study is to characterize the demographic features and physical function of subjects with asymptomatic rotator cuff tears and to compare their shoulder function with control subjects with an intact rotator cuff. Materials and methods: This study enrolled 196 subjects with an asymptomatic rotator cuff tear and 54 subjects with an intact rotator cuff presenting with a painful rotator cuff tear in the contralateral shoulder. Various demographic features, shoulder function (American Shoulder and Elbow Surgeons score and Simple Shoulder Test score), range of motion, and strength were compared. Results: The demographic features of the study and control groups were similar. Hand dominance was associated with the presence of shoulder pain (P < .05). Subjects with an intact rotator cuff had greater but clinically insignificant American Shoulder and Elbow Surgeons (P < .05) and Simple Shoulder Test (P < .05) scores than those with an asymptomatic tear. No differences in functional scores, range of motion, or strength were seen between partial-thickness tears (n = 61) and full-thickness tears (n = 135). Of the full-thickness tears, 36 (27%) were classified as small, 85 (63%) as medium, and 14 (10%) as large. No differences were seen in functional scores among full-thickness tears of various sizes. Conclusions: When asymptomatic, a rotator cuff tear is associated with a clinically insignificant loss of shoulder function compared with an intact rotator cuff. Therefore a clinically detectable decline in shoulder function may indicate an "at-risk" asymptomatic tear. The presence of pain is important in cuff-deficient shoulders for creating a measurable loss of shoulder function. Hand dominance appears to be an important risk factor for pain.