Frozen shoulder

Synonym: adhesive capsulitis of the shoulder

What is frozen shoulder?

Frozen shoulder is one of the most common causes of intrinsic shoulder pain. It is a glenohumeral disorder and can occur in one shoulder or both shoulders simultaneously. Thickening and contraction of the glenohumeral joint capsule and formation of adhesions cause pain and loss of movement¹ .

Frozen shoulder can occur:

• Spontaneously.

• Following rotator cuff lesions/injury.

• In conditions causing immobility - eg, after a cerebrovascular accident or plaster immobilisation.

See the separate Shoulder Pain and Shoulder Examination articles.

Who is affected by frozen shoulder? (Epidemiology)¹

• Adhesive capsulitis occurs in approximately 2-5% of the population with a peak incidence between 40 and 70 years of age.

• It is more common in females and bilateral in 20-30% of cases..

• The incidence of adhesive capsulitis is two to four times higher in those with diabetes than in the general population² . It is also associated with thyroid disease.

Frozen shoulder symptoms¹

The main symptoms are pain and stiffness, caused by formation of adhesive or scar tissue in the glenohumeral joint.

• The vast majority of patients notice pain before stiffness³ .

• It usually affects the non-dominant shoulder although it can occur in either shoulder.

• Bilateral frozen shoulder occurs in around 14% of patients⁴ .

• There is usually a gradual onset of severe pain in the shoulder, which is associated with stiffness.

• Restriction of all shoulder movements, both active and passive.

• Inability to sleep on the affected side.

• Restriction of activities of daily living due to impaired external rotation - eg, driving, dressing.

• There tends to be three phases:
  

  • Phase 1 - severe generalised pain associated with stiffness. Daily activities are limited (eg, putting on a jacket). It can last up to nine months.

  • Phase 2 - pain usually gradually subsides but the shoulder is stiff. Movement can become more limited. External rotation is usually very limited. This phase lasts between 4-12 months.

  • Phase 3 - the shoulder becomes less stiff. There is an increase in the range of movement. This phase usually lasts 1-3 years.

Stiffness, pain and loss of motion with insidious onset are usually the major symptoms.

Investigations

• The diagnosis is clinical:
  

  • The whole shoulder joint may be tender to palpation.

  • The main diagnostic test is the inability to do passive external rotation.

• X-rays are usually only necessary if the presentation is atypical or the patient is not responding to treatment.

• X-rays are commonly normal.

• Consider other causes of shoulder pain.

• Blood tests and radiography should only be performed if red flag symptoms are present. For a list of these, refer to the separate Shoulder Pain article.

Frozen shoulder treatment and management^{5 6 7}

Consider referral to secondary care if pain and significant disability are present for more than six months despite appropriate conservative management.

Despite over a hundred years of treating this condition the most efficacious treatments are still largely unclear⁸ . A holistic approach to treatment should be used, considering psychological and psychosocial factors.

• The first stage is analgesia - paracetamol as first-line with non-steroidal anti-inflammatory drugs (NSAIDs) second-line, provided there are no contra-indications. Use of a transcutaneous electrical nerve stimulation (TENS) machine may also be helpful.

• Encourage early activity.

• Physiotherapy with joint mobilisation combined with stretching exercises have been shown to be better than stretching exercise alone in terms of external rotation, abduction range of motion and function score⁹ .

• Physiotherapy can prevent further reduction in range of motion and eventually increase the range of motion in the affected shoulder¹⁰ .

• Passive mobilisation and capsular stretching are two of the most commonly used techniques for physiotherapy.

• Injection with corticosteroids can reduce pain and duration of symptoms in the early stages.

• The best available data show that a combination of manual therapy and exercise may not actually be as effective as glucocorticoid injection in the short term¹¹ .

• There is, however, no benefit of having ultrasound-guided steroid injection¹² .

• Oral steroids may provide short-term benefit in pain and function¹³ .

• One study has shown that the most effective treatment for frozen shoulder was the combination of the intensive mobilisation and steroid injection with capsular distension, which helped to control inflammation, extend joint space and recover range of movement¹⁴ .

• The management of frozen shoulder amongst surgeons varies substantially. Surgical options include manipulation under anaesthesia and arthroscopic capsulotomy¹⁵ .

Complications

Long-term pain and shoulder stiffness.

Frozen shoulder prognosis

• The condition is usually self-limiting. However, in some patients, symptoms can last for several years or may never fully resolve¹ .

• Over 90% of patients with spontaneous frozen shoulder have been shown to recover to normal levels of function and movement by two years without any treatment¹⁶ .

• Relapses in the same shoulder are uncommon.