What is frozen shoulder?
If you experience stiffness, pain and restricted movement in your shoulder, you may have a condition often referred to as frozen shoulder, but what does "frozen shoulder" really mean?
Other names for frozen shoulder are adhesive capsulitis and shoulder contracture. It is not a type of arthritis and only affects the shoulder joint. The condition occurs when the tissues around the joint of the shoulder – known as the capsule – become inflamed and thickened. Scar tissue forms inside the capsule, which thickens it and makes the joint less flexible.
There may be only mild pain or it can be severe, and it will eventually become difficult to move the arm normally. It can take months or even years for the symptoms to get worse. The stiffness can make it difficult to perform some everyday tasks such as bathing and dressing. There are four main criteria for identifying the condition:
- It comes about slowly
- Pain is felt on top of the shoulder, front and back
- External rotation of the arm is painful and limited, with less than 50% of normal movement
- It's not possible to sleep on the affected shoulder.
There are three stages from the first symptoms of the condition until it gets better – a period that can take between 12 and 42 months (the average is 30 months):
- The first stage is the freezing phase, when the shoulder becomes increasingly painful (especially at night if lying on the affected side), and less able to move; this stage often lasts 2 to 9 months
- The second stage is the frozen phase, when the pain is stable or less but movement of the shoulder is limited (muscles may begin to waste due to lack of use); it can take 4 to 12 months to get through this stage
- The third stage is the thawing or recovery phase, where the range of movement slowly returns, though it may not come back completely; this stage can stretch from 5 months to several years.
Who is more likely to have a frozen shoulder?
It is estimated that 2–5% of people will have a frozen shoulder to some degree, mostly women between 40 and 60 years old. Scientists are not sure why some people have a frozen shoulder, but it often occurs after an injury or overuse, or from a disease such as diabetes (people with diabetes are twice as likely to have a frozen shoulder) stroke, an overactive or underactive thyroid or Parkinson's disease. Immobility such as after surgery can also lead to a frozen shoulder.
For unknown reasons, people with Dupuytren's disease – which appears as small lumps of thickened tissue on the hand that cause the fingers to bend into the palm – are eight times more likely to have a frozen shoulder, and 15–18% of people with a frozen shoulder have or will develop Dupuytren's disease.
Is there any treatment for a frozen shoulder?
Even without treatment, most cases of frozen shoulder will eventually improve, with the shoulder often returning to normal or close to it. However, if you are experiencing pain or limited movement you should seek medical advice. You may be prescribed painkillers such as ibuprofen or naproxen or corticosteroid injections to reduce the pain in the earlier stages, and stretching exercises for your shoulder may be recommended in the later stages. Your GP may refer you to a physiotherapist to help improve the range of movement in your shoulder.
If there is no improvement in symptoms after 6 months and they are severe, surgery may be an option, though surgery is not often necessary.