Finger joint replacement
Finger joint replacements are most commonly performed at the proximal interphalangeal joint (PIPJ) and metacarpal interphalangeal joint (MCPJ). The PIP joint replacements are usually performed for osteoarthritis, whereas the MCP joint replacements are usually performed for rheumatoid arthritis, but also osteoarthritis.
The general principles of surgery are similar for both procedures in that the arthritic ends of the bone that have had the articular cartilage destroyed are prepared to accept the new joint replacement.
The joint replacement stems are inserted into the bone canal and the surrounding bone is allowed to grow onto the implant stem to fix it in place. The end of the implant is left protruding out of the bone and forms a joint with the other side replaced surface.
There are a number of commercially available implants. The most commonly performed in rheumatoid arthritis is a small plastic hinge, whilst newer generation implants (usually of two components) are performed for osteoarthritis.
Who does it affect?
Arthritis usually occurs in people over the age of 40.
Why does it happen?
Osteoarthritis is a simple wear and tear problem. In this situation the articular cartilage, which is the slippery lining of the joint, is worn away. In Rheumatoid arthritis, the disease process attacks the lining of the joint and destroys the cartilage.
Pain and decreased range of movement is the hallmark of finger joint arthritis.
The patient may have a swollen joint that is stiff.
X-rays usually confirm the diagnosis. The features of arthritis on an x-ray are loss of joint space previously occupied by the articular cartilage, new bone formation at the edges of the joint (osteophyte), cysts in the bone and hardening of the ends of the bone with increased white appearance (sclerosis).
Corticosteroid injections in to the joint, usually under x-ray control can often give pain relief. Only one or two are performed before the need to have surgery.
PIP or MCP joint replacement
An incision is made, usually under general anaesthetic or occasionally local anaesthetic, on the back of the finger. The tendons are displaced to one side. The ends of the bone are removed and the medullary canal of each bone is prepared to accept the implant stem. Having inserted the implants the range of movement is assessed, as is the stability and looseness of the joint. The wounds are sutured back into place and the patient is placed in a splint. Within two to three days the patient will be seen by a Therapist, and a structured rehabilitation programme will take place.
A hand therapist will guide the patient through a rehabilitation program. Usually a return to function is seen at 6-8 weeks.
Over 80% of patients are normally satisfied with finger joint replacement surgery.