Background: Although there are many studies describing tests for shoulder instability, there are few assessing the validity of these tests in diagnosing anterior shoulder instability.
Purpose: To assess the validity of the apprehension, relocation, and surprise tests as predictors of anterior shoulder instability.
Study design: Retrospective review of prospectively collected data.
Methods: Forty-six patients with a clear diagnosis of one of the following shoulder disorders were evaluated by four independent, blinded examiners: traumatic anterior instability (18), rotator cuff tendinosis (17), posterior instability (2), glenohumeral osteoarthritis (4), or multidirectional instability (5). Interobserver reliability was also determined.
Results: In subjects who had a feeling of apprehension on all three tests, the mean positive and negative predictive values were 93.6% and 71.9%, respectively. The surprise test was the single most accurate test (sensitivity = 63.89%; specificity = 98.91%). An improvement in the feeling of apprehension or pain with the relocation test added little to the value of the tests. Interobserver reliability was determined to be 0.83.
Conclusions: and
Clinical relevance: The results of this study suggest that a positive instability exam on all three tests is highly specific and predictive of traumatic anterior glenohumeral instability.