Osteoarthritis at the thumb-base

The joints at the base of the thumb often become arthritic as people get older. The usual cause is wear -and-tear arthritis (osteoarthritis) where the smooth cartilage covering the bone surfaces becomes worn out. The condition is commoner in the non-dominant hand, and females are affected more frequently than males. It may give rise to pain at the thumb-base, particularly on opening jars, turning keys, etc, and if it becomes very advanced, it may give a zig-zag appearance to the thumb, as shown in the X-ray.

The severity of pain and the time course of progression are very variable. For example, in some patients there may be very significant signs of arthritis on X-rays, but with minimal associated pain. Treatment is usually conservative in the early stages, e.g. use of splints, painkillers and anti-inflammatory tablets, anti-inflammatory gels. In more troublesome cases, steroid injections may give temporary relief of symptoms, and can be repeated several times. Symptoms will often stabilise over a period of years, and use of these conservative measures may provide time for this to happen.

If the condition does progress to persistent pain, surgery may be indicated. There are a variety of operations, the commonest being a trapezectomy or fusion. The operations usually srequire considerable periods of post-operative splintage and physiotherapy.