Shoulder Joint Arthritis
What do you mean by shoulder arthritis?
This means arthritis of the ball and socket joint of the shoulder. This is the joint between the shoulder blade and the humerus (arm bone). The common types of arthritis which can affect the shoulder are:
- Osteoarthritis
- Rheumatoid Arthritis
- Post Injury Arthritis
- Rotator cuff tear arthropathy
What is osteoarthritis?
This is the “wear and tear” arthritis that one sees in older people. It is a degenerative joint disease. If there is a known cause it is called secondary osteoarthritis (for example congenital disorders of the shoulder) but in many cases there is no obvious cause and in these patients it is called primary osteoarthritis. As a person ages, the water content of the cartilage (which covers the bone surfaces in the shoulder joint) decreases and the cartilage becomes less resilient. It thus becomes susceptible to break down. Breakdown products released from the cartilage can cause inflammation in the joint. Bones spurs or “osteophytes” can form on the margin of the shoulder joint. These changes together with the inflammation can result in significant pain.
What is rheumatoid arthritis?
This is a generalised condition resulting in inflammation of the joint lining (synovium). This can occur at all ages and tends to affect multiple joints in the body. Symptomatic rheumatoid arthritis of the shoulder is typically seen between the ages of 35 and 55 years and is more common in women. Such patients often have associated arthritis of the hand and elbow.
What is Post-injury arthritis?
Post injury arthritis or post-traumatic arthritis is the type of osteoarthritis that occurs following an injury such as a fracture of the shoulder socket or repeated dislocations of the shoulder. Such injuries result in irregularity of the shoulder joint surface. As a result this increases the wear and tear in the shoulder resulting in premature arthritis.
What is rotator cuff tear arthropathy?
Shoulder arthritis can develop following a tear of the shoulder muscles and this is called rotator cuff arthropathy. This tends to be seen in older persons over the age of 70 years. The rotator cuff muscles help to stabilise the “ball” (head of humerus) in the “socket” (glenoid). When these muscles tear, the ball can become unstable in the socket. It tends to move upwards and rub against the overlying shoulder blade. As a result the cartilage can be worn away resulting in arthritis.
What are the symptoms of shoulder arthritis?
The main symptom of shoulder arthritis is pain in the shoulder. This tends to be worse on moving the arm but as the disease progresses there may be significant pain at rest and at night. Limitation of movement in the shoulder or stiffness is another common symptom. Patients may find it difficult to do daily tasks such as combing their hair or changing their shirt etc. A creaking or grating sensation is commonly felt or heard on attempting to move the shoulder.
How is shoulder arthritis diagnosed?
The history and physical examination usually gives the orthopaedic surgeon enough information to make the diagnosis. This is confirmed by taking x-rays of the shoulder. If there is a suspicion of damage to the rotator cuff muscles and then an MRI scan may be ordered. If a joint replacement is being contemplated then a CT scan may be ordered to help plan the surgery. If there is any doubt about the source of the pain, then a local anaesthetic injection into the joint may be performed. For example, some patients may have arthritis in the neck which can produce referred pain to the shoulder. If the shoulder injection relieves the pain, it will confirm that the shoulder is the pain source.
How is shoulder arthritis treated?
Treatment depends upon a number of factors such as previous treatment, age, general health, and degree of pain and disability. The initial treatment of shoulder arthritis is usually non-surgical. This may include:
- Modification of activities to avoid provoking pain.
- Anti-inflammatory tablets and painkillers.
- Disease modifying medication in the case of rheumatoid arthritis (eg methotrexate).
- Physiotherapy
- Injection treatment
- Nutritional supplements
If nonsurgical treatment is not successful in adequately reducing pain then surgery may be indicated.
What are the surgical treatments available for shoulder arthritis?
- Open surgical procedures: these include different types of shoulder replacement and less commonly performed procedures such as corrective osteotomy, open biological resurfacing, shoulder fusion, and shoulder resection arthroplasty.
- Disease modifying medication in the case of rheumatoid arthritis (eg methotrexate).
When are keyhole procedures indicated for shoulder arthritis?
Keyhole procedures may be useful in a number of situations. Arthroscopic debridement involves washing out the shoulder joint by keyhole surgery and removal of any loose unstable cartilage flaps. Drilling of small cartilage defects may also be performed and the tight shoulder capsule can be released at the same time. This may benefit the following patients:
- Patients with mild to moderate shoulder arthritis
- Patients with symptoms due to loose bodies in the shoulder joint or localised damage to the humeral head.
- Disease modifying medication in the case of rheumatoid arthritis (eg methotrexate).
- Patients who were deemed unfit for more major surgery such as shoulder replacement may get some short to medium term improvement in their symptoms. Generally speaking however, keyhole surgery is contraindicated in patients with severe arthritis of the shoulder.
- Patients with mild to moderate shoulder arthritis and restriction of shoulder movement. Patients with restriction of outward movement (external rotation) compared to the opposite side tend to benefit more from this procedure.
- Patients with shoulder arthritis who also have diabetes or thyroid disease may be particularly responsive to arthroscopic capsular releases which reduce the pain from associated adhesive capsulitis.
Arthroscopic biological resurfacing is a new technique which involves inserting a soft tissue graft into the shoulder to cover the worn out socket. It may be considered for young patients who were not candidates for a shoulder replacement. This is technically very demanding and no long-term results are available yet. It may be considered a stopgap procedure to provide medium-term relief of pain in the younger patient until they are old enough to consider having a shoulder replacement.
When are open procedures indicated for shoulder arthritis?
Open surgical procedures are indicated in the older patient with moderate or severe symptomatic arthritis of the shoulder in whom symptoms have not been controlled by nonoperative management. The most commonly performed open procedures are the various types of shoulder replacement. These procedures are very successful in the relief of severe pain that has failed to respond to nonoperative measures. The different types of shoulder replacement are:
- Shoulder resurfacing arthroplasty: this involves replacing the worn out humeral head (the “ball”) with a metallic cap. This is useful if the socket is not badly affected by the arthritis and in those patients in whom it is not possible to replace the socket (for example some patients with rheumatoid arthritis and severe erosion of the socket). It may also be indicated in the younger more active patient in whom there is a significant risk of loosening of the socket. Some patients with shoulder arthritis and a massive rotator cuff tear who are not suitable for a reverse total shoulder replacement (see below) may benefit from a resurfacing arthroplasty.
- Shoulder hemiarthroplasty: this involves replacing the worn out humeral head with half a shoulder replacement (only the humeral side is replaced with a metallic stemmed implant). The indications are of similar to resurfacing arthroplasty. If the humeral head is affected more severely than simply putting a metallic cap on it may not be possible and a stemmed head replacement is advisable to give more stability.
- Total shoulder replacement: this involves replacing both the ball and the socket. The ball is replaced by a metallic implant and the socket is replaced by a plastic implant. Several studies suggest that pain relief following a total shoulder replacement is slightly better than that obtained following replacement of only the humeral head. However this remains somewhat controversial and the choice of a total shoulder replacement versus a shoulder hemiarthroplasty is often made depending upon the needs of the individual patient and the preference of the surgeon.
- Reverse total shoulder replacement: this is a relatively new type of total shoulder replacement which may be indicated in the older patient with shoulder arthritis associated with a massive irreparable tear of the shoulder muscles (the rotator cuff). Such patients tend to have severe pain and are unable to raise their arms above 60°. A successful reverse total shoulder replacement can relieve the pain and restore the ability to raise the arm above shoulder level in such patients. This is however a technically demanding procedure and the complication rate is greater than is the case with the other types of shoulder replacement.
Other open surgical procedures such as corrective osteotomy, open biological resurfacing, shoulder fusion, and shoulder resection arthroplasty are rarely performed and have very specific indications.
What does a shoulder replacement operation involve?
The operation is performed under general anaesthetic usually with a nerve block to provide good post-operative pain relief. An incision is made in the front of the shoulder measuring 10 to 15 cm. Various muscles have to be divided to access the shoulder joint and after implanting the prosthesis these muscles are repaired securely. In order to protect the repair the arm must remain in a sling for 4 to 6 weeks. The patient usually stays in hospital for 1-2 nights. Exercises involving the hand and wrist and elbow are commenced straightaway. Shoulder exercises under the supervision of a specialist shoulder physiotherapist are generally started at about four weeks. The sling is generally discarded at about six weeks. It can take 3 to 6 months to fully recover from the procedure.
What are the possible complications of shoulder replacement?
With all major surgical procedures, complications can occur. The risks of complications however are low. The possible complications include:
- Infection: the risk of developing an infection is low (about 1%). However should an infection developed it can be serious. Very rarely the prosthesis may require removal in order to get rid of the infection. Infections can spread into an artificial joint farm other infected areas and once established in the joint it can be almost impossible for the body’s immune system to eliminate it. Therefore a patient with a joint replacement may require antibiotics before having any dental work or surgical procedures on the bladder or bowels.
- Loosening of the prosthesis: The most common reason for eventual failure of a shoulder replacement is loosening of the prosthesis (usually the socket). This results in pain and if this becomes significant than a repeat operation may be needed. A shoulder replacement can be expected to last for well over 10 years however.
- Dislocation: an artificial shoulder may dislocate. The risk is greatest soon after the surgery. In order to minimise the risk, a sling is used to allow the muscles and other soft tissues to heal around the new joint. Certain movements will need to be avoided and the physiotherapist will instruct the patient regarding these.
- Injury to a nerve or blood vessel: there are some major nerves and blood vessels around the shoulder joint and these may be damaged during a shoulder replacement. All precautions are taken however to avoid this. If damage does occur it turns to be temporary due to stretching of the structures by surgical retractors. If a significant blood vessel is inadvertently damaged during surgery it is repaired at the same time and usually does not result in any long-term problems.
- Development of a blood clot: development of a significant blood clot in the veins is much more common following major surgery to the legs (eg total hip or total knee replacement). It is very rare to develop a significant blood clot in the arm.
- Anaesthetic complications: general anaesthesia is extremely safe. However a very small number of patients can have problems with anaesthesia. The consultant anaesthetist discusses these issues fully with each patient prior to surgery.
Hospitals Attended
