The infraspinatus test: An early diagnostic sign of muscle weakness during external rotation of the shoulder in athletes

J Shoulder Elbow Surg. 1993 Sep;2(5):257-9. doi: 10.1016/S1058-2746(09)80086-4. Epub 2009 Feb 19.

Abstract

Fifty-two men successively elevated dumbbells in increments of 0.5 kg from 1 to 9 kg, performing external rotation of the shoulder with the elbow at 90° of flexion and the forearm at neutral rotation, while lying in the lateral position. Mean values and standard deviations of maximum weight elevated above the horizontal level by the dominant and nondominant arms of 49 men, excluding three athletes with marked infraspinatus muscle atrophy, ranged from 6.2 ± 1.12 kg to 6.7 ± 1.11 kg. Considering the contribution of the infraspinatus muscle to the strength of shoulder external rotation, the elevation of a 3 kg dumbbell, called the "infraspinatus test," is considered to be an early diagnostic sign of muscle weakness during external rotation of the shoulder in athletes who have insidious infraspinatus muscle atrophy.