Small Joint Replacement

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Small joints in the hand may be damaged by rheumatoid arthritis (predominantly inflammation), osteoarthritis (predominantly wear) or the destructive effect of injury to the joint surfaces and surrounding structures (post-traumatic). Badly damaged joints are painful and lose movement. Joint replacement by a silicone rubber spacer (eg the Swanson implant) has been available for over thirty years. It is still often the best type of replacement for the joint with rheumatoid arthritis (see under that heading). The same type of joint replacement has also been used in degenerative and post-traumatic arthritis, but the results have generally not been so good. A new design of joint for these situations has now been made available in the form of a resurfacing device. Several joints of this type are now commercially available. The aim is to provide new joint surfaces on either side of the joint, the new surface being attached to bone by a stem which fits very accurately into the shaft of the bone. In order to retain smooth movement in the joint, the surrounding ligaments must be preserved.   

This type of joint replacement can be used in the MP joint (between the finger and the hand) or the PIP joint (the first joint along the finger). These joint replacements are less often used in the thumb, where the stability offered by joint fusion scores over mobility.   

Resurfacing joint replacements require carefully controlled mobilization in the days following the operation. Results are generally good, but failure can occur if the joint is too loose or too tight, or if it is allowed to dislocate in the early stages.