What is frozen shoulder?
Frozen shoulder is a condition that leads to pain and stiffness of the shoulder. It's also known as adhesive capsulitis or shoulder contracture.
The symptoms tend to gradually get worse over a number of months or years. You'll typically experience shoulder pain for the first two to nine months, which can be severe, followed by increasing stiffness.
The stiffness may affect your ability to carry out everyday activities. In particularly severe cases, you may not be able to move your shoulder at all.
The condition may improve with time, but this can sometimes take several years.
Read more about the symptoms of frozen shoulder .
When to see your doctor
You should visit your doctor if you have persistent shoulder pain that limits your movement.
The earlier frozen shoulder is diagnosed, the more likely it is that treatment can help prevent long-term pain and stiffness.
Read more about diagnosing frozen shoulder .
What causes frozen shoulder?
Frozen shoulder occurs when the flexible tissue that surrounds the shoulder joint, known as the capsule, becomes inflamed and thickened. It's not fully understood why this happens.
The following can increase your risk of developing a frozen shoulder:
- a previous shoulder injury or shoulder surgery
- Dupuytren's contracture – a condition where small lumps of thickened tissue form in the hands and fingers
- other health conditions, such as heart disease and stroke
Most people who get frozen shoulder are between the ages of 40 and 60. The condition is more common in women than men.
Read more about the causes of frozen shoulder .
How frozen shoulder is treated
Most people with frozen shoulder eventually get better, even without treatment. However, appropriate treatment can help reduce pain and improve the movement in your shoulder until it heals.
The type of treatment you receive will depend on how severe your frozen shoulder is and how far it's progressed. Possible treatment options include:
- corticosteroid injections
- shoulder exercises
If your symptoms haven't improved after six months, surgery may be recommended.
Read more about treating frozen shoulder .
Symptoms of frozen shoulder
Pain and persistent stiffness in the shoulder joint are the two main symptoms of a frozen shoulder.
This makes it painful and difficult to carry out the full range of normal shoulder movements. You may find it difficult to perform everyday tasks such as:
- sleeping comfortably
Symptoms may vary from mild, with little interference to daily activities, to severe, where it may not be possible to move your shoulder at all.
Stages of frozen shoulder
The symptoms of a frozen shoulder usually progress gradually over a number of months or years.
There are three separate stages to the condition (see below), which can sometimes be difficult to distinguish. The symptoms may also vary greatly from person to person.
During stage one, often referred to as the 'freezing' phase, your shoulder will start to ache and become very painful when reaching.
The pain is often worse at night and when you lie on the affected side. This stage may last 2-9 months.
Stage two is often known as the 'frozen' phase. Your shoulder may become increasingly stiff, but the pain does not usually get worse and may decrease.
Your shoulder muscles may start to waste away slightly because they are not being used. This stage lasts 4-12 months.
Stage three is the 'thawing' phase. During this period, you will gradually regain some movement in your shoulder. The pain will begin to fade, although it may recur from time to time as the stiffness eases.
Although you may not regain full movement of your shoulder, you will be able to carry out many more tasks. Stage three can last from five months to many years.
Causes of frozen shoulder
Frozen shoulder occurs when the sleeve that surrounds the shoulder joint, known as the capsule, becomes swollen and thickened. It's unclear why this happens.
The shoulder is a ball and socket joint. The end of your upper arm bone (humerus) sits in contact with the socket of your shoulder blade (scapula).
The shoulder capsule is fully stretched when you raise your arm above your head, and hangs down as a small pouch when your arm is lowered.
In frozen shoulder, bands of scar tissue form inside the shoulder capsule, causing it to thicken, swell and tighten. This means there's less space for your upper arm bone in the joint, which limits movements.
Who's most at risk?
It's not fully understood why frozen shoulder occurs, and it's not always possible to identify a cause. However, a number of factors can increase your risk of developing it. These are outlined below.
Age and gender
Most people affected by frozen shoulder are aged between 40 and 60. The condition is more common in women than men.
Previous shoulder injury or surgery
Frozen shoulder can sometimes develop after a shoulder or arm injury, such as a fracture, or after having surgery to your shoulder area.
This may partly be a result of keeping your arm and shoulder still for long periods of time during your recovery. Your shoulder capsule may tighten up from lack of use.
Because of this, it's very important not to ignore a painful shoulder injury and to always seek medical advice.
If you have diabetes , you have a greater risk of developing a frozen shoulder. The exact reason for this is unknown.
It's estimated that people with diabetes are twice as likely to develop a frozen shoulder.
If you have diabetes, the symptoms of frozen shoulder are likely to be more severe and harder to treat. You're also more likely to develop the condition in both shoulders.
This means it's important to have your diabetes checked regularly to make sure it's controlled with the right medication.
Other health conditions
You may have a greater risk of developing a frozen shoulder if you have other health conditions, such as:
- heart disease
- lung disease
- an overactive thyroid ( hyperthyroidism ) or an underactive thyroid ( hypothyroidism )
- breast cancer
- Dupuytren's contracture – where small lumps of thickened tissue form in the hand, causing the fingers to bend into the palm
Other shoulder conditions
Frozen shoulder can sometimes develop alongside other shoulder conditions, such as:
- calcific tendonitis – where small amounts of calcium are deposited in the tendons of the shoulder
- rotator cuff tear – the rotator cuff is a group of muscles that control shoulder movements
Not moving for long periods of time can also increase your risk of a frozen shoulder. This can sometimes happen if you spend time in hospital.
Diagnosing frozen shoulder
See your doctor if you think you have a frozen shoulder, or if you have persistent shoulder pain that limits your range of movement.
Early diagnosis and treatment may help prevent long-term stiffness and pain in your shoulder joint.
Your doctor will examine your shoulder and ask about your symptoms. They may ask:
- when your symptoms started – particularly if it was after an incident, such as a fall
- how severe the pain is
- if you have any other symptoms, such as neck pain
- how your symptoms affect your everyday life
- whether the pain is disturbing your sleep
- whether there's anything that makes the pain better or worse
- if you have any other health conditions, or if you're taking any medication
During the physical examination, your doctor may test your range of movement by asking you to move your arm and shoulder as far as you can in each direction.
Your doctor may apply pressure to parts of your shoulder, to determine where your pain is most severe and what's causing it. They'll also look for any swelling, bruising or muscle wasting.
You may sometimes need to have further tests to rule out other possible health conditions.
For example, if your doctor thinks you may have diabetes , a blood test may be recommended. Frozen shoulder is more common in people with diabetes.
An image of your shoulder joint may be taken to check for any physical signs that could suggest another cause of your symptoms. For example, wear and tear caused by arthritis , or a tear in the tendons around the shoulder.
This may involve:
- an X-ray – to rule out other causes of stiffness in the shoulder, such as arthritis
- an ultrasound scan or magnetic resonance imaging (MRI) scan – if a rotator cuff tear is suspected
Treatment for frozen shoulder
Treatment for a frozen shoulder will vary, depending on the stage of the condition and the severity of your pain and stiffness.
A frozen shoulder may get better over time without treatment, but recovery is often slow and can take at least 18 to 24 months. In some people, the condition may not improve for five years or more.
A number of different treatments can be used to treat frozen shoulder, although it's uncertain how effective they are and which is best.
The treatments described below can help reduce shoulder pain and keep the joint mobile while the shoulder heals.
Early stage treatments
The first stage of a frozen shoulder is the most painful. Therefore, treatment is mainly focused on relieving the pain.
During this stage, your doctor may recommend avoiding movements that make the pain worse, such as stretching. However, you shouldn't stop moving altogether.
If you're in pain, you may be prescribed painkillers, such as:
- a combination of paracetamol and codeine
- a non-steroidal anti-inflammatory drug (NSAID) – such as ibuprofen
Some painkillers are also available from pharmacies without a prescription. Always follow the manufacturer's instructions and make sure you're taking the correct dose.
Taking painkillers, particularly NSAIDs, in the long term can increase your risk of side effects. See the patient information leaflet that comes with your medication for more information.
Read more about the side effects of NSAIDs .
If painkillers aren't helping to control the pain, it may be possible to have a corticosteroid injection in your shoulder joint.
Corticosteroids are medicines that help reduce pain and inflammation. They may also be given with a local anaesthetic .
These injections can help relieve pain and improve the movement in your shoulder. However, injections won't cure your condition and your symptoms may gradually return.
Corticosteroid injections won't be used after the pain has gone from your shoulder and only the stiffness remains.
Having too many corticosteroid injections may damage your shoulder, and the injections often become less effective over time, so your doctor may recommend having no more than three injections. You'll need at least three to four weeks between these.
Read more about corticosteroids .
Later stage treatments
After the initial painful stage, stiffness is the main symptom of a frozen shoulder. Your doctor may suggest stretching exercises, and you may also be referred to a physiotherapist.
If you have a frozen shoulder, it's important to keep your shoulder joint mobile with regular, gentle stretching exercises. Not using your shoulder could make the stiffness worse, so you should continue to use it as normal.
However, if your shoulder is very stiff, exercise may be painful. Your doctor or physiotherapist can give you some simple exercises to do every day at home that won't damage your shoulder any more.
A physiotherapist can use a number of techniques to keep the movement and flexibility in your shoulder. If you're referred to one, you may have treatments including:
- stretching exercises that use specific techniques to move the joint in all directions
- thermotherapy, with warm or cold temperature packs
There's no clinical evidence to show that certain other treatments are effective in treating frozen shoulder, including:
- transcutaneous electrical nerve stimulation (TENS)
- Shiatsu massage
Read more about physiotherapy .
Surgery and procedures
It's uncommon to need surgery for a frozen shoulder, but it may be recommended if your symptoms are severe and other treatments haven't worked after six months.
If this happens, you may be referred to an orthopaedic surgeon (a specialist in conditions that affect the bones and joints). Some of the procedures used to treat frozen shoulder are described below.
Manipulation under anaesthetic
If you're finding the pain and movement restriction difficult to cope with, you can have your shoulder manipulated (moved) while you're under general anaesthetic .
During this procedure, your shoulder will be moved, in a controlled way, to stretch the sleeve (shoulder capsule) surrounding the shoulder joint.
After the procedure you'll usually have corticosteroid and local anaesthetic injected into your shoulder joint to help reduce any pain or swelling.
You can normally go home the same day. Physiotherapy is usually recommended afterwards to help maintain mobility in your shoulder.
Arthroscopic capsular release
Arthroscopic capsular release is an alternative procedure to manipulation. It's a type of minimally invasive or "keyhole" surgery, carried out under general anaesthetic, where two or three small incisions are made around your shoulder.
The surgeon will insert a thin tube containing a light and camera ( arthroscope ) into one of the incisions, so they can see inside your shoulder. A special probe that emits high-frequency radio waves is inserted through the other incisions, and this is used to divide or cut out the thickened parts of the shoulder capsule. Opening up the shoulder capsule in this way should greatly improve your range of movement.
As with manipulation, you can usually go home the same day you have this operation, and you'll probably need physiotherapy afterwards to help you regain a full range of movement in your shoulder joint. Stretching exercises need to be continued for at least three months after surgery.
Shoulder stiffness may return, despite manipulation or surgery, and further treatment may be necessary.
Arthrographic distension (hydrodilatation)
Although it's less commonly performed than the operations described above, a procedure called arthrographic distension or hydrodilatation may sometimes be recommended to treat your frozen shoulder.
This treatment is carried out under local anaesthetic, which means you'll be awake while it's carried out, but your shoulder will be numbed.
It may be performed by a specialist orthopaedic surgeon using a local anaesthetic and corticosteroids, or saline with corticosteroids. X-ray guidance may sometimes be needed.
This procedure usually only takes about 15 minutes, and you can go home the same day. As with the other procedures described above, physiotherapy may be recommended afterwards to help you regain a good range of movement in your shoulder.
There's some evidence that hydrodilatation may result in less pain and greater movement, although the effects may be no better than a corticosteroid injection.