Comparison of Peak Torque according to Size of the Rotator Cuff Tear Patients

ABSTRACT

OBJECTIVE: To investigate the peak torque of shoulder according to the size of the rotator cuff tear. METHOD: With 26 patients of unilateral rotator cuff tear, we measured the concentric isokinetic peak torque of shoulder, using Con-Trex isokinetic dynamometer (CMV AG, Deubendorf, Switzerland). We measured flexion, extension, abduction, adduction, external rotation, and internal rotation torques and calculated the peak toque ratio of flexion/ extension, abduction/adduction and external rotation/internal rotation. Before the test, we injected 1% lidocaine to the subacromial bursa to minimize the error that can be caused by pain. The difference of peak torque according to the size of tear was compared. RESULTS: Comparing the peak torque between affected and sound side, significant difference in flexion, extension, abduction, adduction, internal rotation, and external rotation were shown, but there were no difference in peak torque's ratio in flexion/extension, abduction/adduction, and internal rotation/external rotation. When we compared the peak torque according to the tear size, it didn't show significant difference and also there were no difference of peak torque's ratio in flexion/extension, abduction/adduction, internal rotation/external rotation. CONCLUSION: When we measured the shoulder's strength of rotator cuff tear, peak torque decreased in all motion. But the peak torque's loss and peak torque's ratio is not related with size of tear.