Rehabilitation is the cornerstone of most shoulder treatments. After an acute injury, physical therapists may provide passive modalities to reduce pain and inflammation such as icing and iontophoresis. As part of the initial evaluation, the physical therapist may evaluate for imbalances outside the shoulder joint that may contribute to the source of shoulder pain. The shoulder is part of a kinetic chain, meaning that it is connected to other parts of the body by joints and soft tissues. Inflexibility or weakness in the buttocks or spine may affect mechanics in the shoulder. Thus, whole-body fitness strength and flexibility are considered in addition to the individual components of the shoulder.  

The scapular stabilizers (e.g., trapezius, rhomboids, serratus anterior, latissimus dorsi) are of particular importance in rehabilitation of the shoulder because the scapula is the base upon which all activities of the shoulder rest.⁵ Thus many exercises will focus on scapular control. Likewise the rotator cuff muscles are strengthened individually and as a unit. Exercises should emphasize use of the rotator cuff as a unit, with multidirectional forces.

Range of motion will be aggressively maintained and improved. Avoiding full range of motion because of pain can result in loss of range of motion due to adhesive capsulitis.

Surgical

Surgical interventions are available for many problems of the shoulder. Surgery is often reserved for patients who do not improve with rest, medication, and physical therapy. 

Rotator cuff repairs for full or partial thickness tears may be performed arthroscopically or with an open surgical approach, in which the joint is exposed via an incision visualized directly without the use of a camera. While it is generally accepted that rotator cuff tears do not heal without surgery, physical therapy alone can make a painful rotator cuff tear pain free. The risk of not having surgery is that the tear could worsen, causing the involved muscles to retract. With time, the muscle fibers are replaced by fatty infiltrates. After significant fatty infiltration, a rotator cuff tear may not be reparable. Recovery after surgery may take 4-6 months. 

Most cases of rotator cuff tendonitis without rotator cuff tear respond to physical therapy. In cases in which physical therapy does not bring significant improvement, open or arthroscopic decompression of the subacromial space may provide relief. Repair of the rotator cuff, if indicated, may be performed at the same time. In both rotator cuff tears and tendonitis, 3 months of physical therapy is often attempted before considering surgery.  

In cases of adhesive capsulitis, patients who do not have significant relief after 12 months of physical therapy may be offered manipulation under anesthesia and capsular release. In this procedure, the patient is anesthetized while the surgeon forcibly moves the joint to the extremes of available range of motion in order to restore mobility to the joint. The joint capsule, which can be scarred and tight, may also be opened surgically to allow improved range of motion. 

In glenohumeral joint arthritis, the surface of the joint may be resurfaced so that bones and cartilage articulate more smoothly. The success of resurfacing depends on the quality of the bone in the joint. For more advanced disease, a total joint replacement, in which the head of the humerus and glenoid fossa are replaced by prosthetic equipment, is also available. The average recovery time after total shoulder replacement is 3 months.  

Surgical treatment of glenohumeral instability depends on the age of patients and their history of previous instability. Patients under the age of 20 have an 80% chance of having recurrent dislocations compared to patients over the age of 30, who have a 10% chance. Surgery for instability is usually reserved for recurrent dislocators and elite athletes. These procedures may be open or arthroscopic, and usually involve reattachment of the anterior capsule and/or labrum to the glenoid rim.  

If the cause of shoulder pain is traumatic injury, for example AC joint separation or fracture, the need for surgery is determined by the severity of injury.