There’s a surgery for painful arthritis of the thumb joint. It has something to do with filling in the space where the joint rubs. What is this procedure, and why do doctors use it?

The procedure is called excision arthroplasty. The term excision means to “take out.” In this surgery, the surgeon takes out a small bone at the base of the thumb and fills in the space with a rolled up section of tendon. The soft tissue forms a “false joint.”

The main goal of this surgery is to ease pain where the surfaces of the thumb joint are rubbing together. The doctor uses a piece of tendon to form a “spacer” that separates the surfaces of the joint. Unlike a fusion surgery that simply binds the joint together, excision arthroplasty can help take away pain while allowing the thumb joint to retain some movement.