Osteoathritis is the degeneration of a joint through wear and tear.
The main joint at the base of the thumb is called the trapeziometacarpal joint. This joint carries a lot of force when the thumb is used, yet allows for a complex range of movements, including rotation. It is this load-bearing and movement that causes the wear and tear that brings on osteoarthritis.
Osteoarthritis can cause aching, especially between the thumb and the side of the index finger. The pain may lead to a sense of weakness when you pinch or grip. Actions such as opening the lid of a jar, or turning a key in a door, can be painful and difficult. The base of the thumb may become swollen and may crunch audibly during certain movements. It may also become misshapen. It is this pain and disability that often encourages people to seek surgical interventions.
What surgery is available, and what techniques are involved?
Before surgery is pursued, other treatments such as thumb splints or steroid injections may be carried out. If these treatments fail to support the thumb or reduce the pain, then surgery may be considered. The options include:
• Joint stabilisation: this involves either realignment of the bone or ligament reconstruction using a tendon; suitable only for a minority of patients who have an unstable joint but little damage to the surfaces of the joints.
• Trapeziectomy: this involves the complete removal of the trapezium bone; recommended if the joint above or below this bone are affected by arthritis. Some surgeons fill the gap left by the bone, with adjacent tissue.
• Trapeziectomy with ligament reconstruction: this is performed if there are concerns that the thumb appears too slack to sit securely in the new joint created by the removal of the bone.
• Arthrodesis: fusion surgery, which is normally reserved for younger patients; has the disadvantage of stiffening the thumb.
What can I expect as a patient?
Trapeziectomy is the most commonly performed surgical operation for osteoarthritis of the thumb. The operation is usually performed under general anaesthetic, supplemented by local anaesthetic. As a patient, you will need to stay in hospital for one or two nights after the operation. It will leave a scar on the back of your hand, and a bulky dressing to protect it. In the days following the operation, hand elevation is very important to prevent swelling and stiffness.
Stitches are usually removed at around two weeks after the operation, and the plaster may be changed for a lighter weight splint, which you will need to wear for up to six weeks. From about four weeks you can begin exercising the hand, using techniques passed on by a hand therapist. It normally takes six-to-nine months for strength in your thumb and hand to return, but improvement is usually steady. Although your strength in this area may never be as good as it was, most patients notice significant pain reduction.
Infection can occur, and severe stiffness can affect about 5% of patients.
Surgery to treat osteoarthritis in the thumb and hand is available on the NHS.