Shoulder anterior-posterior laxity measurement in a healthy population

The assessment of the shoulder anterior-posterior laxity has been performed using an instrumented mechanical device. The anterior-posterior translation measurement facilitates the generation of normative data of non-pathologic shoulders in a healthy population. The descriptive laboratory study has also investigated the impact of gender and exercise frequency on shoulder laxity. The glenohumeral anterior-posterior joint laxity was assessed in sixty-four subjects using an instrumented mechanical device. The tests were carried out on the left shoulder followed by the right and the duration of each test session was approximately thirty minutes. The sagittal plane translation measurement of the dominant and non-dominant shoulder was not statistically significant (p > 0.05) and varied from 17.0 to 24.8 mm with a mean of 20.7 ± 2.0 mm. On comparing the sagittal plane translation measurement of male (22.3 ± 0.9 mm) and female (19.0 ± 1.1 mm) subjects and active (21.3 ± 1.7 mm) and non-active (19.3 ± 1.7 mm) sports participants, a significantly higher variation was observed between them (p < 0.05). There was no significant variation (p < 0.05) between the overhead and non-overhead sports categories. The results indicate that being active in sports, irrespective of overhead/non-overhead sports and gender differences are likely to influence the shoulder anterior-posterior laxity. Objective measurements of glenohumeral joint laxity can be used as a reference for diagnosis of shoulder anterior-posterior laxity. Key-Words: Shoulder anterior-posterior laxity