Frozen shoulder is a condition where the range of motion of the shoulder joint is severely restricted. There is typically a painful stage, a “frozen stage”, and a “thawing” stage. Frozen shoulder develops slowly. Each stage can last several months. The “thawing” stage usually lasts the longest.
Causes of Frozen Shoulder
Frozen shoulder (adhesive capsulitis) starts with inflammation of the shoulder joint capsule. The inflammation may be the result of an injury (such as a rotator cuff tear) but may occur for no apparent reason. Not using the shoulder for a prolonged period of time can lead to frozen shoulder. Having diabetes or thyroid problems increases the risk of developing frozen shoulder. It is most common in people between the ages of 40 and 60 and is more common in women. It is interesting to note that, even when there is no known cause, usually only one shoulder is affected.
The shoulder joint capsule encloses the main shoulder joint (glenohumeral joint). The shoulder joint capsule is attached to the bones of the joint but is loose enough to allow the bones to move freely. The joint capsule has a fibrous outer membrane and an inner membrane (the synovial membrane) that produces synovial fluid. Synovial fluid is a sticky fluid that lubricates the joint. There may also be a lack of synovial fluid in a frozen shoulder.
Stages of Frozen Shoulder
Inflammation in the shoulder joint capsule causes pain, which worsens when the shoulder is moved. When there is shoulder pain that is aggravated by motion there is a tendency to stop using the shoulder. The inflammation itself also limits motion somewhat. At this stage pain is the main problem – not actual stiffness.
Inflammation damages tissues, and as it heals scar tissue forms. The normally loose joint capsule thickens and shrinks. If the shoulder is not moved, scar tissue is more likely to fuse together surfaces in the shoulder joint and limit motion. Pain often decreases during this “frozen” stage, while range of motion decreases significantly.
A year or more of physical therapy may be needed to “thaw” (restore mobility to) the shoulder. Progress is gradual.
Treatment of Frozen Shoulder
Treatment involves reducing the pain and regaining the shoulder’s range of motion through stretching exercises. A physical therapist can help guide the patient through exercises and advise what exercises to perform at home. Recovery from a frozen shoulder can take up to 18 months of physical therapy. Shoulder muscles also atrophy from lack of use; a physical therapist can advise when strengthening exercises for the shoulder should begin.
Massage therapy can reduce pain and improve function of the shoulder. Deep tissue massage stretches muscles and softens and stretches adhesions around the shoulder to increase mobility. Massage therapy increases circulation to speed healing and decreases pain.
Anti-inflammatory medications reduce both pain and inflammation. NSAIDs (non-steroidal inflammatory drugs) are often recommended though they may cause stomach irritation and there is a risk of developing ulcers with long-term use. Ice is also useful for pain and inflammation. An injection of cortisone (a powerful anti-inflammatory) into the shoulder joint sometimes helps.
If symptoms do not improve within 18 months of physical therapy the shoulder may be manipulated while the person is under general anesthesia to break up adhesions and “unfreeze” the shoulder. This procedure may be performed earlier to speed recovery. Rarely, the shoulder joint has become too stiff to be manipulated without risking breaking the arm. In these cases, arthroscopic surgery can be performed to cut the adhesions (an arthroscopic capsular release). Other problems, such as a torn rotator cuff, that may have triggered the frozen shoulder syndrome may also need repairing.
Shoulder pain or stiffness should be diagnosed and treated early. Stretching exercises may prevent adhesions and stiffness from occurring in an injured shoulder. Preventing frozen shoulder is much easier than treating it.