There are different types of arthritis that affect the shoulder joint: osteoarthritis, rheumatoid arthritis, post-traumatic arthritis, rotator cuff arthritis and arthritis associated with avascular necrosis.
Also known as “wear and tear” arthritis, osteoarthritis generally affects older patients who present with pain and loss of movement of the shoulder. The smooth cartilage of the shoulder becomes frayed, thinned and even worn away to eventually leave bone rubbing on bone.
Currently, the treatments are aimed at either controlling symptoms with activity modification, painkillers and injections or with shoulder replacement surgery.
Rheumatoid arthritis is a chronic inflammatory arthritis that tends to affect the small joints of the hands symmetrically. The shoulders can be affected with pain and swelling of the joints.
There have been significant advances in the medical treatment of rheumatoid arthritis, often supervised by the Rheumatologists, but if symptoms are not controlled significant pain relief can be achieved by shoulder replacement surgery.
Arthritis can develop after injury to the shoulder, such as fracture, dislocation and some surgical treatments for shoulder instability. Activity modification, painkillers and injections can be helpful and if symptoms persist then shoulder replacement surgery may be offered.
Avascular Necrosis (AVN)
Avascular necrosis (AVN) of the humeral head (shoulder ball) can occur if the blood supply to the humerus is disrupted. The bone of the shoulder dies and eventually collapses, leading to painful arthritis and loss of function.
AVN is not very common. It may be caused by excessive alcohol, high dose steroid use, sickle cell disease or traumatic disruption to the blood supply (as seen after some fractures).
Rotator Cuff Arthritis
The rotator cuff keeps the humerus “centred” in the shoulder socket (glenoid). Large rotator cuff tears (torn shoulder tendons) cannot maintain the ball in the socket. The humerus moves up, and over time arthritis of the shoulder can develop as abnormal shoulder movements wear away the lining of the joint. Patients present with pain and loss of function of the shoulder, and X-rays confirm arthritic change and upward migration of the humerus. Activity modification, painkillers and injections can be helpful and if symptoms persist then shoulder replacement surgery, in form of reverse shoulder replacement, may be offered.
Shoulder arthritis surgery
Arthroscopy (keyhole surgery)
Some patients with early arthritis of the shoulder may benefit from debridement (clear out) of the shoulder, particularly if a rotator cuff tear is present.
Arthroplasty (replacement surgery)
Shoulder resurfacing only replaces the top of the ball of the shoulder.
Total shoulder replacement (anatomical)
Replaces the ball of the shoulder as well as the shoulder socket, with metal and plastic respectively.
Reverse shoulder replacements are total shoulder replacements with the ball put on the socket side and the socket put on the ball side. This alters the centre of rotation, and mechanics, of the joint allowing other muscles around the shoulder to move the joint when the rotator cuff is absent or deficient.