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

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.