Dr Steve Carter


Carpometacarpal (CMC) Osteoarthritis

Osteoarthritis "wear & tear" is very common in the base of the thumb particularly in women after age of 50. Very often on the non dominant side.

  • The thumb counts for 40% of the function of the hand, so there is a tremendous amount of force going through a shallow saddle shaped joint.
  • This results in excessive sheer forces and the cartilage of the thumb starts to wear out.

Patients present with pain in the base of the thumb. They may also notice a deformity of the thumb, with a swelling at the base. The hand may be weak and typically they are unable to open a tight jar or tap. There may also be a loss of dexterity and range of motion. Overall pain at the base of the thumb is the most important symptom.


  • We initially adopt a conservative approach (anti-inflammatories may be useful or splinting of the thumb). Most importantly: many patients get significant long term relief with an intra-articular steroid injection.
  • If conservative treatment fails, surgical options are
    1. CMC joint arthrodesis (we very seldom do this and it is for the younger patient).
    2. CMC joint excision arthroplasty: In other words removing the arthritic bone and placing a tendon as a new space. This was our preferred option for many years. It is still a highly reliable technique, but rehabilitation takes an extended period of time, so I now favour CMC joint total arthroplasty.
    3. CMC joint total arthroplasty is now our favoured technique. Touch total arthroplasty for the first CMC joint offers advantages over traditional trapeziectomy in terms of preserving joint motion, stability and reducing pain. It maintains thumb length, provides stability and enables a quicker recovery compared to trapeziectomy. What are the advantages of total arthroplasty? Firstly touch total arthroplasty preserves the trapezoid bone, a vital structure in the thumb’s overall functionality. By retaining this bone the procedure maintains the joint’s stability and helps distribute loads more effectively, ensuring improved thumb movement and strength. Secondly, this technique allows for greater preservation of surrounding soft tissues and ligaments. By minimizing disruption to these structures, touch total arthroplasty offers enhanced stability and a reduced risk of postoperative complications promoting a much quicker recovery period. Additionally, the procedure’s design replicates the joint’s natural anatomy, promoting a more physiological movement of the thumb. This mimicking of the joint’s original mechanics is vital in restoring a more natural range of motion and function, resulting in better overall patient satisfaction.
      Furthermore, patients often report significant reduction in pain levels and a substantial increase in thumb mobility, enabling them to resume daily activities with greater ease and comfort.
      1. The surgery is performed as day case surgery, usually under general anaesthetic, but can also be done under a local regional block. The procedure takes 40 minutes and I use a 5cm incision over the base of the thumb.
      2. Following the procedure, you are placed in a bulky dressing for 10 days.
      3. After 10 days the dressing and sutures are removed. The occupational therapist will make a soft thumb splint which is worn for 4 weeks.
      4. Physiotherapy and full range of movement is started from day 10.