Rotator Cuff Tear
The rotator cuff is a group of four muscles which envelope the ‘ball’ of the shoulder joint (the humeral head). The muscles help lift the arm but are also instrumental in keeping the humeral head down and away from the overlying bone in the shoulder, the acromion. Between the acromion and the rotator cuff muscles is the subacromial space and providing this space is preserved there should be ample room for the tendons to glide under the acromion. If there is not enough space, then the tendons can be damaged.
A rotator cuff tear can develop following a number of different patterns of injury. Two of the most common are;
- Degenerative Tears; the rotator cuff tendons may become weakened over time due to natural degenerative changes that occur. These are often referred to as “age related changes”. The weakened rotator cuff tendons are then compromised in their ability to keep the humeral head (ball) away from the overlying bone, the acromion. Thus can be further compounded by a build up of bone on the under surface of the acromion (a bone spur) which can also occur as we get older. If contact develops between the rotator cuff and the under surface of the acromion such that the two surfaces rub, and then pain, clicking and restrictions in movement can occur. This is referred to as subacromial impingement and shoulder movements, particularly those that involve elevation to, and above, shoulder height can particularly aggravate the shoulder. If the impingement continues then bursitis/inflammation can cause the progressive thickening and scarring of the bursa such that movement is further restricted. If the impingement continues unchecked then the rotator cuff tendons may undergo degeneration and eventually result in a tear of the tendon. This may result in more pain and weakness.
- Traumatic Tears; if too much load is placed through the it is not uncommon for the rotator cuff tendon to develop either a partial or full thickness tendon tear. Although this is unusual in young patients, as one gets older it becomes increasingly common, so much so that partial and small full thickness tears can be seen in up to 50% of 60-70 year olds. However, although most of these don’t result in symptoms, if the tear reaches a certain size, or if it affects an important part of the rotator cuff tendon, significant pain and loss of function can occur. As young patients will usually have a normal rotator cuff prior to any injury, the magnitude of an injury in a young person usually has to be significant for it to result in a rotator cuff tear, however in older patients, more minor injuries can result in devastating rotator cuff injuries. This is usually because the shoulder was already undergoing some degenerative changes prior to the injury and was therefore already prone to developing a rotator cuff tear.
The symptoms of a rotator cuff tear include;
- Pain can be present both at rest and with activity.
- Pain can be referred to the front of the shoulder and also down the side of the arm.
- Pain is usually made worse when the arm is taken through an arc of movement to, and above, shoulder height. Pain can also be present when you try to lower your arm back to your side.
- Sudden severe pain may occur on lifting or reaching movements.
- Night pain and difficulty lying on the affected side may occur.
- Stiffness and restricted movement
- Undertaking activities, especially those involving taking your hand behind your back, may become difficult and painful.
- There may be a complete inability to lift the arm or the arm may just feel weak.
- Movement may be possible but only by posturing the shoulder to enable the movement.
- Repetitive use of the shoulder, especially overhead.
- Injury; falls or after the sudden loading or lifting of heavy weights.
- After prolonged weakening, deterioration or impingement.
- X-rays can be used to assess the shoulder and also confirm the presence of associated osteoarthritis of the shoulder or acromioclavicular (ACJ) joints.
- Ultrasound scans are often the most accurate way of assessing the quality of the rotator cuff tendons and are particularly useful in assessing partial thickness rotator cuff tears.
- MRI scans (Magnetic resonance imaging) can be used to assess rotator cuff tears and are very useful for helping to plan surgery and predict the outcome of any reparative surgery.
- Conservative treatment comprising of rest, activity modification and the use of anti-inflammatory medications.
- Physiotherapy; strengthening exercise and physiotherapy regime can be used to improve the range of shoulder movement by optimising the remaining shoulder and rotator cuff muscles.
- Injection treatments; injections to the subacromial space, or sometimes suprascapular nerve blocks can be used to ease the symptoms associated with a rotator cuff tear, however such treatments will not address the tear itself. Furthermore, if subacromial space injections are used inappropriately, they can also cause further damage to the rotator cuff tendons. This is especially relevant when managing partial thickness rotator cuff tears.
- Surgery; Surgery has an important role in the management of rotator cuff tears. The choice of the appropriate treatment is based on the site and size of the rotator cuff tear, the condition of the rest of the shoulder and the patient’s expectations and needs. The options can include;
Causes & Risk factors
Although the diagnosis of a rotator cuff tear can often be made clinically from the history and examination, imaging is always used to confirm the diagnosis and help to determine the most appropriate treatment.
There are a number of treatments available for rotator cuff tears. Each treatment is individualised to the patient and will be based on the nature and size of the rotator cuff tear, the patient’s age and their activity levels and expectations. However, often more than one treatment modality is used to address the tear and its symptoms. The options include;
Rotator Cuff repair; If the symptoms associated with the rotator cuff tear are such that treatment is necessary, a rotator cuff repair can be undertaken. The aim of the surgery is initially to arthroscopically examine the shoulder to confirm the diagnosis and then create the best surgical environment before undertaking the repair. The surgery will entail a full debridement, bursectomy and usually a subacromial decompression. The torn rotator cuff is then mobilised and then manipulated to see if it can be returned to the position from which it was torn. If it can, then the repair is undertaken by physically stitching the tendon back to its bony origin, known as the footprint. To achieve this, anchors are used to secure the sutures used in the repair into the bony footprint. Using arthroscopic techniques a repair is the completed. This is usually a completely arthroscopic procedure but mini-open techniques are sometimes also used. In these instances, the majority of the repair is performed arthroscopically such that the outcome and recovery times are not adversely affected.