Predicting Recurrent Instability of the Shoulder (PRIS): A Valid Tool to Predict Which Patients Will Not Have Repeat Shoulder Instability After First-Time Traumatic Anterior Dislocation.

Abstract

To assess the sensitivity, specificity, and validity of the Predicting Recurrent Instability of the Shoulder (PRIS) tool in people with a first-time traumatic anterior shoulder dislocation. Prospective cohort study. People with first-time traumatic anterior shoulder dislocation (n = 85), aged 16 to 40 years, were recruited within 12 weeks of their shoulder dislocation and followed prospectively for 1 year post injury. We calculated the sensitivity, specificity, negative predictive value, and positive predictive value of the PRIS tool. Of the 75 participants available for 1-year follow-up, 57 (76%) did not have recurrent shoulder instability. With the PRIS tool cut point set at 0.895, the tool's sensitivity was 39% (95% confidence interval [CI]: 17.3%, 64.3%) and its specificity was 95% (95% CI: 85.4%, 98.9%). The area under the curve was 0.69 (95% CI: 0.55, 0.84; P = .01). The PRIS tool correctly identified 54 of the 57 (95%) who did not have recurrent instability (accuracy, 81%; 95% CI: 70.7%, 89.4%). Negative and positive predictive values were 83% (95% CI: 77.2%, 87.7%) and 70% (95% CI: 40.2%, 89.0%), respectively. The PRIS tool can predict those who will not have further shoulder instability in the year following first-time traumatic anterior shoulder dislocation. The PRIS tool cannot accurately predict those who will have recurrent shoulder instability. J Orthop Sports Phys Ther 2020;50(8):431-437. doi:10.2519/jospt.2020.9284.