Consultant surgeon Mr Brian Cohen continues our series on therapeutic exercises with a guide to subacromial impingement. A patient information leaflet and full video are available online
Subacromial impingement can be caused by either an injury to the rotator cuff or spurs of bone forming on the anterior margin of the acromion. It is due to the rotator cuff and the covering bursa coming into contact with the undersurface of the acromion during this movement.
The typical symptoms are of pain over the cape of the shoulder and upper arm in the mid arc of abduction or, for instance, when reaching above shoulder height to a high shelf. Symptoms are more common in those over 40 years of age.
The shoulder may be painful to lie on at night and may cause the patient to wake from sleep. The diagnosis is supported by the presence of a subacromial spur on X-ray, thickening of the subacromial bursa on ultrasound scan with impingement on dynamic scanning, or a subacromial bursitis on an MRI scan.
Physiotherapy along with anti-inflammatory medication and analgesia is the first line of treatment. One of the actions of the rotator cuff is depression of the humeral head. Physiotherapy is aimed at posture and scapula setting as well as strengthening the cuff to encourage active depression of the humeral head on elevation of the arm.
Self-training may prove as effective as formal supervised physiotherapy.1 Studies also indicate that physiotherapy may be as effective as arthroscopic surgery in the treatment of subacromial impingement.2,3
Two useful exercises are shown in the online video and the box, right.
Isometric external rotation and abduction against a wall involves the patient standing against a wall with their elbows bent, applying pressure gently to the wall through the fist, keeping their elbow away from it. They then press their elbow against the wall and attempt to bring the elbow out to the side, avoiding pressing with their hand. Both movements should be held for 10 seconds before relaxing and repeating 15 times.
Scapula retraction and depression involves the patient sitting in good posture and gently bringing the shoulder blade back and down, holding the position for 10 seconds before relaxing and repeating 10 times.
Refer any patient whose symptoms get worse with exercise or who cannot do them at all.
Twenty minutes a day for three months.
Mr Brian Cohen is a consultant surgeon at the London Orthopaedic Clinic
The London Orthopaedic Clinic holds free monthly education sessions for GPs. For more information: www.londonorthopaedic.com
scapula retraction and depression subacromial impingement Patient leaflet: Exercises for subacromial impingement
Shoulder pain leaflet Video: Exercises for subacromial impingement