Base of thumb arthritis

This is a very common condition where 10% of the population may seek help. Patients typically present in the 6th or 7th decade of life, but those who are genetically susceptible or have had an injury to their thumb may have symptoms earlier than this.

Symptoms

The main symptom is pain at the base of the thumb. In the early stages the pain is limited to certain activities like pinching or gripping. As the arthritis progresses, the pain can be present during normal every day usage, and finally it can be present continuously.

Diagnosis

The diagnosis is clinical, which means that it is made on the basis of the symptoms described by the patient and the findings on examination of the painful thumb and the rest of the joints in both hands. X-rays are taken to confirm the diagnosis and demonstrate the severity of the arthritis in terms of the anatomy of the involved bones and joints.

Treatment

Initially if the pain is not severe, activity modification, pain killers and hand therapy including special splints may be all that is necessary. If these measures are insufficient, steroid injection into the painful joint usually gives pain relief for two to three months but is not curative. Once these non-surgical options are exhausted and you would like something more done, then there are surgical options.

Surgery

The most common operation is a ‘trapeziectomy’, which means removal of the trapezium bone at the base of the thumb which research has demonstrated to be the safest procedure. However, I may recommend an alternative procedure such as ligament reconstruction, cutting of the pain nerves to the joint (denervation) or joint replacement if I believe this would be more appropriate for you. The surgery is usually carried out under regional or general anaesthesia as a day case operation and you can go home the same day. Your thumb will be in a plaster cast initially which will be changed to a thermoplastic splint for a total of 6 weeks and you will have hand therapy after the operation. Driving is permitted 6 weeks after the operation. You should see pain relief three months after the operation but the full benefit may not be felt for 9 months.

Complications

Minor complications such as wound infection, poor scarring or problems with bleeding occur in less than 5% of patients. Major complications are rare but it is important to realise that surgery does not give absolute pain relief from this condition. Most patients say that their pain is 80% better. Most of the remaining 20% report no change in their pain levels but a few experience markedly increased pain and stiffness due to complications of surgery, including complex regional pain syndrome (CRPS) NHS Information on CRPS. Thumb strength (key and tip pinch) usually remains weaker than a normal thumb and may not be any stronger than before surgery. You may become more aware of thumb weakness following surgery when the thumb is no longer painful. You are likely to continue to have trouble opening tight screw-top bottles and jars. If you have a good outcome in terms of pain relief one year after surgery then it is likely this will be permanent.

Please see my publication on the subject