Interposition arthroplasty of thumb CMC joint


Pain in the base of the thumb from arthrosis is a common occurrence and markedly restricts thumb function.


Surgery for thumb CMC joint arthrosis is recommended when pain and stiffness and deformity of the thumb significantly restrict use of the hand.

Preoperative Instructions

No specific pre-operative planning is required for this operation.


A curved incision is made directly over the dorsum of the thumb CMC joint. After careful exposure and retraction of the branches of the radial nerve, the joint is exposed and the distal end of the trapezium bone is removed to create a space. A coil of palmaris longus tendon is then sutured into the space to act as a new bearing surface. The capsule is closed to stabilise the joint and a scaphoid cast is applied. A block will be inserted to ensure your pain is well controlled when you wake up.

Postoperative Instructions

You may be able to go home on the day of surgery with the cast if you are comfortable. The cast will stay on for six weeks and after which it is removed, the sutures are removed and stress ball exercises and physiotherapy are commenced.


There are always some risks with any operation. The problems that may rarely arise after this surgery are blood clots, wound infection or perhaps there may be some damage to the median nerve or one of its branches. There may be tightness from the cast due to post-operative swelling and the cast may have to be split. All these problems are exceedingly rare.

Related Information

Thumb CMC joint osteoarthrosis