An injury to the rotator cuff is a common cause of shoulder weakness.
- Dr Duckworth
The rotator cuff is the collective term for a group of tendons around the shoulder.
Your shoulder has numerous muscles and tendons controlling movement and stability of the shoulder. Among these are the tendons of the rotator cuff. The rotator cuff is composed of four tendons that blend together to help stabilize and move the shoulder. The rotator cuff is the collective term for a group of tendons, which includes the supraspinatus, infraspinatus, teres minor, biceps and subscapularis. These tendons pass under a bony-ligamentous arch.
Loss of integrity of the rotator cuff is a common cause of shoulder weakness. Those patients with large rotator cuff defects have difficulty raising the arm or rotating it out towards the side.
Learn more about rotator cuff repair surgery
Problems can arise within the rotator cuff when it is:
Irritation, bruising or fraying of the tendons can occur with repetitive use of the arm eg. when carrying heavy luggage or during sports like golfing and tennis. When the tendons are inflamed but not torn then it is called tendinitis. The pain is primarily from the inflamed tendons being rubbed by the bony ligamentous arch. This can also result in a bursitis, where the bursa above the tendons also becomes irritated and swollen which causes pain. The biceps tendon can also become frayed or unstable and may require treatment at the same time.
Tearing of the rotator cuff can occur when these tendons become irritated and swollen and eventually wear out or else they can occur as a result of a major force eg, direct injury. Most tears have some degree of preceding wear changes. Any accidents or injuries that might occur at work, sport or a fall may precipitate a tear of these weakened tendons.
Tears of the rotator cuff tendons occur with increasing frequency as the population gets older. It is unusual for a patient younger than 40 years to have a tear whereas up to 50% of patients over the age of 75 years have a tear in one or other rotator cuff tendon. A tear of the rotator cuff does not always have to be painful.
What are the symptoms?
The most common symptoms which cause a patient to seek medical advice are:
How is a diagnosis made?
In determining the diagnosis it is most important to take a thorough history from the patient and also to examine them to assess their range of motion and ability to use and raise their arm. After this, one or more of the following tests may be ordered – a plain xray, ultrasound or MRI in order to assess the condition of the bones, tendons and ligaments.
How are these problems treated?
In patients who have an acute rupture of their rotator cuff after a fall, surgical management is generally indicated to restore function to the arm, however the majority of rotator cuff tears are degenerative in nature and occur over time. These ones rarely require surgery and are best managed with non-operative management.
Non-operative treatment includes
If this does not help in reducing the pain or if there is poor shoulder function then surgery maybe recommended. For those patients with a rotator cuff tear, a rotator cuff repair is performed. If a patient with a rotator cuff tear does not have surgery, then the tendon tear may, in some cases, increase in size. For others the shoulder may continue to function reasonably for many years.
When rotator cuff tears are relatively recent and when a significant force was required to tear the tendon, the chances of regaining shoulder strength by rotator cuff surgery are good. Conversely, when the defect is longstanding and occurred without a major injury, the quality and quantity of tissue available for repair may not be sufficient for the restoration of good shoulder function.