Isokinetic muscle strength parameters for shoulder movements.

A study was carried out on shoulder muscle strength using an isokinetic dynamometer device, and normal parameters were established on 20 men and 20 women for a total of 80 shoulders. This population consisted of fit, athletic individuals with a mean age of 26·65 years and 25·35 years for the women and men; respectively. Peak torque, angle of peak torque, and arc of maximum strength (= peak±2 N m) were measured. Emphasis was placed on the arc of maximum strength in that it may reflect a more functional measurement than the single angle value for peak torque. For all movements women were approximately 50% as strong as men. There were no significant differences between the means for dominant versus non-dominant arms. The strongest muscle group was the adductors, with a mean peak torque of 28·8 N m for women and 48·-0 N m for men. With 48 N m internal and external rotation, women had a significantly greater range of motion than men but the peak torques remained around the neutral position.