Base of thumb arthritis

What is it?

The thumb is an important component of the hand, it is vital in powerful/grasping hand functions as it acts as a 'post' against which the hand can hold objects, it is also vital in fine movements / functions of the hand, such as when picking up a small coin or writing etc. The joint at the base of the thumb is called the "carpo-metacarpal joint", and is responsible for taking much of the load and providing the vast mobility of the thumb, that is it does alot of work through life!

As the joint wears it develops arthritis, this is termed CMC (carpometacarpal) joint arthritis of the thumb. As with most other joints it occurs from use of the joint over the years but may also be associated with injuries or over use. It results in pain, stiffness, and deformity of the affected joint. There may also be weakness associated.

For individuals who rely on their hands for work or sporting activities etc, the loss of function can be quite disabling. It is important to know also that there are a number of other possible causes for pain in that part of the hand, and that they can co-exist or mimic each other, which Dr Ihsheish can talk you through.


A thorough clinical assessment is required to make the diagnosis, this may well also require the use of imaging studies such radiographs (x-rays). Dr Ihsheish can discuss with you the suspected diagnosis and any other problems, and the merits of the various management options available.

As with most arthritic joints, the first line treatment consists of

  • pain relief and anti-inflammatories
  • activity modification, and
  • appropriate splinting of the joint.

If these are not successful then surgery may be required.

Surgery aims at removing the painful articulation. In recent decades many surgical options have been developed and used, and many have good results pubished in the scientific literature. Dr Ihsheish can discuss the appropriate ones with you for your case if needed. In general, following surgery, you will be seen at two weeks for a wound check, no sutures will usually be visible (absorbable sutures are used), you will be in a splint for 4-6 weeks, and arrangements for physiotherapy will be made.