CMC Joint Replacement

The carpometacarpal (CMC) joint is located at the base of the thumb, where the first metacarpal bone meets the trapezium bone in the wrist. This joint allows the thumb to move in multiple directions and is important for gripping, pinching and everyday hand function.

Arthritis can develop when the cartilage within the CMC joint wears down. This can cause:

• Pain at the base of the thumb
• Pain when gripping or pinching
• Reduced thumb strength
• Stiffness and reduced movement
• Difficulty opening jars, turning keys or using tools
• Tenderness or swelling around the thumb joint

As the arthritis progresses, everyday activities can become increasingly difficult.

Treatment for CMC joint arthritis depends on the severity of your symptoms, the degree of joint damage and how the condition affects your hand function.

Non-surgical treatments may be appropriate for mild or moderate arthritis and can include:

• Activity modification
• Hand therapy and exercises
• Splinting
• Anti-inflammatory medication where appropriate
• Corticosteroid injections in selected cases

Surgery may be considered when pain and loss of function persist despite non-surgical treatment.

Dr Bissell will assess your symptoms, thumb movement, strength and imaging before discussing whether CMC joint replacement is appropriate for you.

CMC joint replacement is a surgical procedure that replaces the arthritic surfaces of the thumb CMC joint with an artificial joint implant.

The procedure aims to:

• Relieve pain caused by arthritis
• Preserve movement of the thumb
• Improve grip and pinch function
• Allow a return to everyday hand activities

CMC joint replacement is an alternative to trapeziectomy and other surgical procedures used to treat advanced thumb CMC arthritis. The most appropriate procedure depends on your individual circumstances.

CMC joint replacement is designed to relieve the pain associated with thumb arthritis while maintaining useful movement of the thumb.

Potential benefits include:

• Pain relief from the arthritic CMC joint
• Preservation of thumb movement compared with procedures that remove the joint
• Improved grip and pinch function
• Return to everyday activities following recovery
• A more functional thumb for activities requiring gripping and pinching

The results of surgery vary between patients, and Dr Bissell will discuss the potential benefits and limitations of CMC joint replacement with you.

Your thumb will usually be protected in a splint or supportive dressing following surgery. The length of immobilisation will depend on the procedure performed and your individual recovery.

Hand therapy is an important part of rehabilitation following CMC joint replacement. Exercises are gradually introduced to restore thumb movement, strength and function.

You will need to avoid heavy lifting and forceful gripping during the early stages of recovery. Your return to driving, work, sport and other activities will depend on your progress and the demands placed on your hand.

Dr Bissell will provide individualised advice about wound care, splinting, hand therapy and your return to normal activities.

As with any surgery, CMC joint replacement has potential risks and complications. These may include:

• Infection
• Bleeding or bruising
• Scarring or scar sensitivity
• Stiffness or reduced movement
• Persistent pain
• Nerve irritation or injury
• Implant loosening, wear or failure
• Joint instability or dislocation
• Fracture around the implant
• The need for further surgery

Your individual risks will depend on your health, the severity of your arthritis, your anatomy and other factors. Dr Bissell will discuss the expected benefits, risks and alternatives with you before surgery.

CMC joint replacement and trapeziectomy are established surgical options for advanced thumb CMC arthritis. They use different approaches to treat the arthritic joint, and each has potential benefits and risks.

CMC joint replacement aims to relieve pain while preserving movement of the thumb. Trapeziectomy removes the arthritic trapezium bone and does not require an artificial joint implant.

The most appropriate procedure depends on factors including your age, activity level, joint condition, anatomy and treatment goals. Dr Bissell will discuss the available options with you.