Frozen shoulder (sometimes called adhesive capsulitis of the shoulder) is a condition where a shoulder becomes painful and stiff. Shoulder movements become reduced, sometimes completely 'frozen'. It is thought to be due to scar-like tissue forming in the shoulder capsule. Without treatment, symptoms usually go but this may take up to 2-3 years. Various treatments may ease pain and improve the movement of the shoulder.
What are the symptoms of frozen shoulder?
The typical symptoms are pain, stiffness, and limitation in the range of movement of a shoulder. The symptoms typically have three phases:
- Phase one - the 'freezing', painful phase. This typically lasts 2-9 months. The first symptom is usually pain. Stiffness and limitation in movement then also gradually build up. The pain is typically worse at night and when you lie on the affected side.
- Phase two - the 'frozen', stiff (or adhesive) phase. This typically lasts 4-12 months. Pain gradually eases but stiffness and limitation in movement remain and can get worse. All movements of the shoulder are affected. However, the movement most severely affected is usually rotation of the arm outwards. The muscles around the shoulder may waste a bit as they are not used.
- Phase three - the 'thawing', recovery phase. This typically lasts between one and three years. The pain and stiffness gradually go and movement gradually returns to normal, or near normal.
Symptoms often interfere with everyday tasks such as driving, dressing, or sleeping. Even scratching your back, or putting your hand in a rear pocket, may become impossible. Work may be affected in some cases.
There is great variation in the severity and length of symptoms. Untreated, on average the symptoms last 2-3 years in total before going. In some cases, it is much less than this. In a minority of cases, symptoms last for several years.
Who gets frozen shoulder?
Frozen shoulder affects about 3% of adults at some stage in their life. It most commonly occurs in people aged between 40 and 65 years. It is more common in women. It is more common than average in people who have diabetes and some other conditions, including overactive thyroid disease.
Either shoulder can be affected but most commonly it is the non-dominant shoulder - that is, the left shoulder in a right-handed person. In about 1 in 5 cases the condition also develops in the other shoulder at some stage.
Note: frozen shoulder is not a form of arthritis and other joints are not affected.
What causes frozen shoulder?
The cause is not clear. It is thought that some scar tissue forms in the shoulder capsule. The capsule is a thin tissue that covers and protects the shoulder joint. The scar tissue may cause the capsule to thicken, contract and limit the movement of the shoulder. The reason why the scar tissue forms is not known.
A frozen shoulder occasionally follows a shoulder injury. However, this is not usual and most cases occur for no apparent reason.
Do I need any tests?
The diagnosis of frozen shoulder is usually made by a doctor's examination. You may also have an X-ray or an MRI scan of your shoulder joint. These tests are usually only done if the diagnosis is not clear, to exclude another cause of your symptoms. So, many people will not actually need any tests.
What are the treatment options for frozen shoulder?
The aim of treatment is to ease pain and stiffness; also, to keep the range of shoulder movement as good as possible whilst waiting for the condition to clear. One or more of the following may be advised to help ease and prevent symptoms:
Paracetamol may be advised first to try to control the pain. Codeine is a stronger painkiller which may be used as an alternative to, or in addition to, paracetamol. Constipation is a common side-effect from codeine. You can take ordinary painkillers in addition to other treatments.
Examples anti-inflammatory painkillers include ibuprofen, diclofenac and naproxen. These drugs work by helping to ease pain and also by reducing any swelling (inflammation) in your shoulder. There are many different brands. Therefore, if one does not suit, another may be fine. Side-effects sometimes occur with anti-inflammatory painkillers. Always read the leaflet that comes with the drug packet for a full list of cautions and possible side-effects.
These are commonly advised. The aim is to keep the shoulder from 'stiffening up' and to keep movement as full as possible. For most benefit, it is important to do the exercises regularly, as instructed by a doctor or physiotherapist.
Many people are referred to a physiotherapist who can give expert advice on the best exercises to use. Also, they may try other pain-relieving techniques such as warm or cold temperature packs and transcutaneous electrical nerve stimulation (TENS) machines.
An injection into, or near to, the shoulder joint brings good relief of symptoms for several weeks in some cases. Steroids reduce inflammation. It is not a cure, as symptoms tend to gradually return. However, many people welcome the relief that a steroid injection can bring.
An operation is sometimes considered if other treatments do not help. Techniques that are used include:
- Manipulation. This is a procedure where the shoulder is moved around by the surgeon while you are under anaesthetic.
- Arthroscopic capsular release. This is a relatively small operation done as 'keyhole' surgery. It is often done as a day-case procedure. In this procedure, the tight capsule of the joint is released with a special probe.
Although surgery has a good rate of success it does not help in all cases.
Note: it is really important to avoid immobilising your shoulder - for example, with a sling or even a plaster cast. This will actually make recovery more difficult and will take longer to improve.
What is the outlook?
The symptoms of frozen shoulder can persist for 18 months to 3 years or more. However, the vast majority of people with a frozen shoulder do recover to normal levels of function and movement by two years, even without any treatment.
It is very uncommon to have frozen shoulder more than once in the same shoulder.
Dr Tim Kenny
Dr Louise Newson
Dr John Cox