Frozen shoulder is also known adhesive capsulitis. This is a painful condition of the shoulder which can cause severe limitation in movement.
How common is it?
It is quite a common condition occurring in up to one in 20 people. Most people affected by it are between the ages of 40 and 60 and it is more common in women. In about 10 to 15% of patients the other shoulder becomes affected as well- usually within five years.
Why does it occur?
No one really knows why. Most people get it for no known reason. It is more common in people with diabetes and is often more severe and more resistant to treatment in diabetics. It can sometimes occur following an injury or following an operation on another part of the body.
What happens to the shoulder in this condition?
The shoulder joint is the most mobile joint in the body. It is normally covered by a loose structure called the capsule. The looseness of the capsule allows a tremendous range of movement in the normal shoulder. In frozen shoulder , the shoulder capsule becomes inflamed and very thickened and contracted. As a result it “grips” the ball in the socket and does not allow it to move normally. It forms an actual physical block to movement.
What are the symptoms and signs?
The symptoms are usually slow in onset and can be spread over a number of months or even years. Frozen shoulder is typically described as having three stages:
Stage one (Freezing stage):
This lasts from 10 to 36 weeks. It often starts with a nagging constant pain in the shoulder, worse at night which responds poorly to painkillers and anti-inflammatory tablets. This is due to the inflammation of the capsule mentioned above. The combination of pain and contracted capsule makes it very difficult for the patient to perform normal day-to-day activities such as getting dressed, brushing hair and driving.
Stage two (Frozen stage):
This typically lasts for 4 to 12 months. During this stage the pain gradually subsides at the shoulder remains stiff. When the shoulder is at rest the patient is generally pain-free but sudden movements produce pain and there is pain at the extremes of movement.
Stage three (Thawing stage):
This is the recovery stage. It can last from one to 4 years. There is a gradual recovery in the range of movement. The pain gradually fades away though it can recur intermittently as the range of movement improves.
How is it diagnosed? Are any tests are required?
The diagnosis is made on the basis of the history and the physical examination. Generally speaking very few tests are required. In the older patient x-rays may be ordered to rule out any underlying arthritis of the shoulder. Scans are generally not needed unless the doctor is unsure about the diagnosis.
How is it treated?
Treatment depends upon the stage of the disease. In the early stages, treatment is directed towards relieving the pain. The treatment may include:
- oral painkillers
- oral anti-inflammatory tablets
- corticosteroid injections into the shoulder joint
- avoidance of painful activities and the limitation of shoulder movements within a pain-free range.
- a gentle home exercise program once the pain settles.
In the later stages, treatment is directed towards regaining movement. Injections are not used in this stage. Treatment may include:
- Physiotherapy to stretch out the contracted capsule
- A more aggressive home exercise program
- Hydrodilatation (stretching or rupture of the shoulder capsule by injecting saline and corticosteroid into the shoulder joint under x-ray control). This is particularly useful in those patients not fit for surgery. It has limitations however, particularly in diabetics in whom the disease is resistant to treatment.
- Surgery (arthroscopic capsular release): Surgery is indicated if nonoperative measures such as physiotherapy fail to improve shoulder movement. Previously a closed manipulation of the shoulder was the procedure of choice. More recently the advent of keyhole surgery has revolutionised the treatment of frozen shoulder. A simple keyhole procedure performed as a day case can restore a full range of movement to the shoulder.
What does keyhole surgery involve?
This involves insertion of a camera into the shoulder and division of the abnormal contracted structures under direct vision. An added advantage of the procedure is that any coexisting abnormality such as a prominent bone spur can be treated at the same time. The surgery is done as a day case usually under a general anaesthetic, though sometimes it is done after putting the arm to sleep and giving the patient some light sedation. After surgery it is important to retain the range of movement in the shoulder. Physiotherapy and a home exercise program are started almost immediately. This helps to prevent the scar tissue from forming again.