MANAGEMENT — Although precise data is lacking, many patients with atraumatic multidirectional shoulder instability are treated effectively with a focused rehabilitation program designed to strengthen the stabilizing muscles of the shoulder and improve neuromuscular coordination of glenohumeral and scapulothoracic movement [28]. Those who do not respond well to physical therapy may require surgical repair. Surgical options for stabilizing the glenohumeral joint in patients with MDI include open and arthroscopic capsular plication, rotator interval closure, and labral augmentation [29-33].
Initial treatment — Patients should initially be advised to rest and restrict overhead activities, such as reaching, pushing, pulling, and lifting. Daily applications of ice (15 minutes every four to six hours) and a short course (eg, two to three days) of antiinflammatory medication (eg, ibuprofen) help to relieve pain in patients with concomitant bursitis or rotator cuff tendinopathy.
Physical therapy — A rehabilitative exercise program that focuses on correcting scapulothoracic dyskinesia and strengthening the dynamic stabilizers of the glenohumeral joint is often effective [12,18]. The goal is to improve the dynamic control and positioning of the humeral head in the glenoid. Precise data is lacking, but observational studies and abundant clinical experience suggests that most compliant patients have good results with an appropriate rehabilitation program, as determined by diminished pain and improved stability over time [28]. When treating the overhead athlete, many clinicians incorporate stretching exercises into the rehabilitation program with the goal of maintaining a normal range of motion equal to the contralateral side, while correcting for the increased external rotation commonly seen in the dominant arm [34].
Strengthening the scapular stabilizers, including the trapezius, rhomboids, and serratus anterior, increases scapular stability, which is required for proper rotator cuff function [17,35]. Once proper scapulothoracic control is achieved the program begins to incorporate rotator cuff strengthening exercises. (See "Rehabilitation principles and practice in shoulder impingement syndromes", section on 'Step one: Improve scapular stability' and "Rehabilitation principles and practice in shoulder impingement syndromes", section on 'Step two: Strengthen the rotator cuff'.)
When appropriate strength is achieved in the scapulothoracic stabilizers and the rotator cuff, the patient begins a functional training program designed to simulate the stresses the patient’s shoulder will encounter during their usual athletic and work activities. An example of one exercise progression that might be used in such a program consists of push-ups against a wall, followed by standard push-ups, and ultimately pushups on a tilt board. The instability created by the tilt board helps the patient to improve proprioception and dynamic joint stability [36,37]. Once rehabilitation is completed, most patients need to continue performing exercises to maintain shoulder strength and function.
Persistent symptoms — Patients with concurrent symptoms attributable to subacromial impingement or rotator cuff tendinopathy may benefit from a short course of nonsteroidal antiinflammatory therapy or a subacromial glucocorticoid injection (figure 1). The resulting reduction in pain often allows patients to participate more actively in their rehabilitation program. (See "Rotator cuff tendinopathy", section on 'Glucocorticoids'.).
Indications for orthopedic referral — The natural history of multidirectional shoulder instability is to improve slowly as the tissues gradually stiffen with age. Nevertheless, referral to an orthopedic surgeon for consideration of surgical correction is warranted in patients with persistent pain or recurrent episodes of dislocation despite full participation in a well-designed physical therapy program for 6 to 12 months. Recurrent dislocation in particular must be managed appropriately to avoid the development of premature glenohumeral osteoarthritis. (See "Glenohumeral osteoarthritis".)
In addition, patients with unidirectional (eg, posterior) shoulder instability, particularly those who are not improving with physical therapy, should be referred to an orthopedic surgeon for evaluation. In many cases, the pathology responsible for unidirectional instability is amenable to surgical repair [38].
