The relationship between anterior glenohumeral laxity and proprioception in collegiate baseball players

Abstract

Objective: To determine if a relationship exists between anterior glenohumeral (GH) laxity and proprioception.

Design: Cross-sectional study.

Setting: University biomechanics laboratory.

Participants: Thirty asymptomatic collegiate baseball players.

Independent variables: Anterior GH laxity.

Main outcome measures: Proprioception (active joint position sense) at positions of 75 degrees of external rotation, 30 degrees of external rotation, and 30 degrees of internal rotation were measured using an isokinetic dynomometer. Anterior GH laxity was measured using an instrumented arthrometer.

Results: Linear regression analyses showed that there were no relationships between anterior GH laxity and active joint position sense at 30 degrees of GH internal rotation and 30 degrees of GH external rotation (r = 0.21, P = 0.13). However, there was a moderate positive relationship between anterior GH laxity and joint position sense at 75 degrees of shoulder external rotation (r = 0.56, P = 0.001).

Conclusions: These results suggest that shoulder proprioception in 75 degrees of external rotation decreases as anterior GH laxity increases. These results may prove beneficial in the prevention, evaluation, and treatment of various shoulder injuries associated with GH laxity.