ARTHRITIS AT THE BASE OF THE THUMB

Basal joint arthritis is a condition that irritates or destroys the joint at the base of the thumb. The cartilage that normally covers the ends of the bones begins to deteriorate, allowing the bones to rub against each other.

The result is significant damage that can cause severe pain and limit drastically thumb movement. Common activities such as opening jars, turning door knobs or buttoning clothing can become difficult or impossible if the condition continues to worsen.

Diagnosis of arthritis at the base of the thumb is based upon a carefully performed physical examination and review of medical history with confirmation by X-rays, which allow the arthritis to be staged as early, mild, moderate or severe.

In the early stages, splinting, and medications may be beneficial. In more severe cases, surgery may be necessary.

The goal of surgery is to eliminate the pain at the base of the thumb by creating a new joint. When surgery is necessary, the procedure can improve the position of the thumb, its range of motion and the hand’s strength for pinching and grasping.

There are 2 types of surgery that are currently available that maintain motion. The traditional surgery which is useful in patients with advanced disease involves removing the entire trapezium bone and then using a tendon from the forearm to suspend the thumb and to act as an interposition material. This is referred to a “Ligament Reconstruction Tendon Interposition” Arthroplasty (LRTI).

The newer approach to earlier stage painful arthritis at the base of the thumb involves only removing only 2mm of the diseased portion of the trapezium bone. A spacer made of woven biodegrabable material is then inserted between the two bones. This eliminates the rubbing of the two rough surfaces and diminishes pain. Thumb length which is important in strength is also maintained.

Pre-operative xray of thumb arthritis. Postoperative xray after placement of spacer. Notice the separation between the trapezium bone and the thumb metacarpal bone.