Overview
The rotator cuff is a group of four muscles and their tendons surrounding the shoulder joint, providing stability and enabling arm rotation and elevation. Rotator cuff injuries range from tendinopathy (inflammation or degeneration) and partial tears to full-thickness tears. They are a common cause of shoulder pain and reduced arm function.
How common is it?
Rotator cuff problems are the most common cause of shoulder pain, accounting for about 70% of shoulder presentations in primary care. Full-thickness tears affect 20 to 30% of adults over 60, many asymptomatically.
Causes and risk factors
Rotator cuff injuries result from acute trauma, repetitive overhead activity, or degenerative age-related changes that weaken the tendon and make it susceptible to tearing.
Common risk factors
- Age-related tendon degeneration (most common cause of full-thickness tears)
- Overhead repetitive activity (painting, tennis, swimming, throwing sports)
- Acute trauma: fall onto outstretched hand or shoulder, heavy lifting
- Poor posture and shoulder biomechanics
- Subacromial impingement (narrowing of the space through which tendons pass)
- Smoking (reduces tendon blood supply)
- Diabetes (associated with tendon stiffness and tears)
Symptoms
- Pain in the outer shoulder and upper arm, typically worse with reaching overhead or behind the back
- Pain at night, especially lying on the affected side
- Weakness when lifting the arm or rotating the shoulder
- Difficulty combing hair, reaching behind the back, or fastening a bra
- Catching or clicking sensation in the shoulder
- Limited range of movement in severe cases
When to see a doctor
See a GP or physiotherapist for shoulder pain lasting more than 6 weeks. Seek urgent orthopaedic assessment for acute complete loss of shoulder strength after trauma (suggesting acute full-thickness tear).
Diagnosis
Clinical assessment: specific tests (Neer, Hawkins-Kennedy, empty can, drop arm sign). X-ray excludes bony pathology. MRI is the gold standard for soft tissue characterisation, distinguishing partial from full-thickness tears and guiding surgical decisions.
Treatments
Physiotherapy and rehabilitation
Supervised exercise programme targeting rotator cuff strengthening, scapular stabilisation, and posterior capsule stretching. Resolves symptoms in 60 to 80% of patients with non-massive tears over 3 to 6 months.
Corticosteroid injection
Ultrasound-guided subacromial injection provides significant short-term pain relief (4 to 12 weeks) and allows engagement with physiotherapy. Not a long-term solution and should not be repeated more than 3 times.
Surgical repair
Arthroscopic rotator cuff repair for complete tears causing significant disability, younger patients, or those failing conservative treatment. Success rates 70 to 85% for full-thickness repair. Rehabilitation takes 6 to 12 months.
Self-care and lifestyle
- Begin gentle pendulum exercises as soon as pain allows to prevent shoulder stiffening
- Avoid lying on the affected shoulder at night (use a pillow for support)
- Warm up properly before overhead activity
- Address posture (rounded shoulders increase subacromial impingement)
Prevention
Rotator cuff strengthening exercises, correct technique during overhead sports, and addressing posture reduce injury risk. Stopping smoking and optimising diabetes control protect tendon integrity.