The shoulder is a ball and socket joint and is very mobile. The ball is kept in its socket through the help of various ligaments, cartilages and tendons.
In the 1930s a surgeon called Michael Burman introduced a procedure using a keyhole camera inserted in the shoulder joint and since then the equipment, techniques and expertise have significantly improved. The majority of shoulder joint problems can now be treated by this minimally invasive surgery.
Shoulder pain is a very common symptom and may affect patients of any age. The cause of pain varies with age. In middle-aged and older patients it is usually caused by arthritis, which is normally associated with worn or torn tendons surrounding the shoulder joint (the so-called ‘rotator cuff’).
In such patients, overhead activity, especially if repeated, is a risk factor that causes pain. What happens is that arthritis of the upper bone of the shoulder (known as the acromion) pinches the tendon underneath it, causing the tendons to become irritated and inflamed. This is referred to as ‘impingement’. The tendons then become thickened and cause further problems as they become larger. Such a condition is sometimes also known as ‘swimmer shoulder’ or ‘thrower shoulder’. Impingement may also be associated with a thinning or tear of the shoulder muscles, as well as arthritis of the small joint of the shoulder, known as acromioclavicular (AC) joint.
In middle-aged patients this often presents itself with pain of the outer aspect of their arm, which usually becomes worse when they lift it, reach out for objects or sleep on their side. They may also develop weakness of movement if there is an associated tear of the muscles around the shoulder. The condition is usually progressive, which is of an increased significance if the person has a manual job.
Impingement is diagnosed by taking a detailed medical history and physical examination. X-rays may show bony spurs which cause the impingement.
The condition can be successfully treated by pain relief medicines such as aspirin, ibuprofen and naproxen, which need to be taken for six to eight weeks. In addition, patients are advised to do daily stretching of the shoulder under a warm shower, to apply ice packs to the shoulder, to avoid repatative activities and to undertake physical treatments such as physiotherapy to help align the shoulder movements and build up the muscles around the shoulder.
In some cases, injection of a steroid or long-acting anaesthetic may be effective for various period of time; however, if such injections are repeated this may result in the weakening of muscles and tendons. If these non-operative treatments are ineffective, surgery in the form of arthroscopic (keyhole) surgery is recommended.
In this operation a camera and various instruments are inserted into the shoulder joints through approximately one-centimetre incisions, allowing the surgeon to visualise and work on the joints. In cases of impingement, the excess bone pinching the tendon as well as the inflamed tissue under the acromion (the upper bone of the shoulder) can be shaved away under direct observation in order to widen the space around the muscles so that they do not rub or catch on surrounding tissues. Moreover, any associated tears in the muscle insertions around the shoulder can be repaired.
The advantages of performing these procedures through keyhole surgery have been borne through the results of several clinical studies. One advantage is that the operation of arthroscopy is usually done as a day case. The visualisation of the joint during this type of operation is much better than with open techniques.
The recovery is also much shorter with keyhole surgery than with open surgery, as the damage to the soft tissues around the shoulder is minimised. The pain levels, complications and risks such as infection are significantly less than with traditional open techniques. Moreover, the patient can return to work and exercise sport much quicker than with open surgery.
Alistair Pace is a consultant orthopaedic surgeon.