Correlation of 3-Dimensional Shoulder Kinematics to Function in Subjects With Idiopathic Loss of Shoulder Range of Motion

Background and Purpose. People with idiopathic loss of shoulder range of motion (ROM) have difficulty completing activities of daily living. This investigation was performed to determine the association between active glenohumeral ROM and function and to develop a multiple regression equation to explain variation in function in people with idiopathic loss of shoulder motion. Subjects and Methods. This was a comparative study of 21 subjects (18 female, 3 male), using measurements of shoulder kinematics and administration of the Shoulder Rating Questionnaire (SRQ). Electromagnetic tracking sensors monitored the 3-dimensional position of the scapula and humerus throughout active shoulder motions. Correlations were performed between the active ROMs of interest and various demographic factors and the SRQ. A multiple regression equation was generated. Results. A multiple regression equation including scapular-plane abduction, external rotation at the side, external rotation at 90 degrees of abduction, and weight explained 69% of the variation in the SRQ scores. Discussion and Conclusion. The results suggest that active ROM can be used to predict function in people with idiopathic loss of shoulder ROM.