COLORADO SPRINGS, Colo. — About half of patients who underwent 6 months of nonoperative management for isolated posterior glenohumeral instability required arthroscopic stabilization, according to a presentation.
“Nonoperative treatment of posterior instability results in failure of approximately 50%. Increased posterior acromial height, greater posterior humeral subluxation and greater posterior glenoid bone loss are risk factors for failure. Failure of nonoperative management is associated with a progressive bone loss of approximately 4%,” Jonathan F. Dickens, MD, said at the American Orthopaedic Society for Sports Medicine Annual Meeting.
In the retrospective review, researchers studied 123 nonoperatively treated shoulders from active-duty service members from the Military Health System’s electronic medical record database with isolated posterior shoulder instability defined as an isolated posterior labral tear. Nonoperative management was defined as physical therapy for a minimum of 6 months. Minimum follow-up was 2 years.
Jonathan F. Dickens
Researchers identified patients who underwent nonoperative management and subsequently had a repeat MRI of the initially injured shoulder, and the two studies were compared to evaluate for changes in glenoid bone loss, glenoid morphology, cartilage injuries and the presence of concurrent pathology.
Primary outcome was glenoid changes associated with failure of nonoperative management. Secondary outcomes included evaluation of potential risk factors for failure of nonoperative management, including glenoid bone loss, glenoid version and posterior humeral head subluxation. Dickens said failure was defined as recurrent pain with a positive exam, inability to return to activity, revision surgery or medical discharge from the military due to the shoulder.
Overall, 47% of the nonoperatively treated shoulders failed nonoperative management. Mean follow-up was 3.4 years, Dickens said. Failed nonoperative treatment was associated with progression of posterior glenoid bone loss from 2.7% to 6.5%. The failure group had a significantly greater humeral head subluxation ratio. Of patients who failed nonoperative management, 17 patients had repeat MRIs for comparison with initial MRIs, which revealed a greater significant increase in glenoid bone loss. Mean time from index MRI and repeat MRI was 488 days.