Accuracy of the Anterior Apprehension Test as a Predictor of Risk for Redislocation after a First Traumatic Shoulder Dislocation

Abstract

Background The treatment options for a first traumatic shoulder dislocation in a young patient are either nonoperative care or primary surgery. It would be valuable to find patient-specific assessments that could predict the risk for redislocation in these patients and thereby identify those who would benefit from primary surgery. Hypothesis The supine apprehension test, performed after completion of physical therapy in first traumatic shoulder dislocators, can predict risk for redislocation. Patients with a positive test would be at very high risk for redislocation and therefore would be candidates for primary surgery. Study Design Cohort study (prognosis); Level of evidence, 2. Methods Men aged 17 to 27 years who sustained first traumatic shoulder dislocations were treated in a shoulder immobilizer for 4 weeks and then treated according to a physical therapy protocol. At the 6-week follow-up, an anterior apprehension test was performed to assess risk of redislocation. Follow-up of patients was done at 3 months, 6 months, 1 year, and 2 years. Follow-up continued yearly for up to another 2 years. Results Fifty-two men with a mean age of 20.3 years (standard deviation, 2.5) participated. Seventy-nine percent were combat soldiers. Twenty-four participants (46.2%) sustained redislocation. The minimum follow-up period was 24 months (range, 24-48 months; mean, 39.6 months). Redislocations were sustained in 36.8% of participants with negative apprehension tests and 71.4% with positive tests (P = .03). The odds ratio was 4.285 (95% confidence interval, 1.129-16.266). The sensitivity of the apprehension test was 41.7% and the specificity was 85.7%. Conclusion The anterior apprehension test performed 6 to 9 weeks after a first traumatic dislocation is not a definitive tool to predict risk for recurrent dislocation. It can, however, categorize patients into groups at higher and lower risk for recurrence. The redislocation rate found in this study is less than that of previous reports.