One of the most common degenerative conditions of the hand that is seen by orthopedists is arthritis of the thumb. In orthopaedics, we refer to it as first carpometacarpal (CMC) joint arthritis or basal joint arthritis.
The thumb joints have a large range of motion which allow us to pinch, grasp, and manipulate objects. In a healthy joint, the bones that make up the thumb joint normally glide easily with motion. As the cartilage wears, friction develops and the bones begin to rub together. This is the development of osteoarthritis.
Symptoms associated with thumb arthritis include pain, tenderness, and in some cases swelling towards the base of the thumb. Activities that involve gripping or pinching, can trigger pain. Progressively, certain activities become harder to perform and mobility declines. As the arthritis advances, the appearance of the thumb joint can change and a bony ridge can form over the joint that can often be felt. Typically, this is a problem identified in those over 50 years old, although it does affect younger patients in some cases.
The diagnosis of first CMC or basal joint arthritis is made by taking a patients history, physical examination and radiographs. The typical findings from radiographs include loss of joint space and bone spurring.
Non-surgical treatment is usually initiated which may include the use of non-steroidal anti-inflammatory medication, a splint to immobilize the joint, and activity modification. A cortisone injection also may be beneficial to provide temporary relief of pain and inflammation.
When non-surgical treatments fail to provide relief, surgery may be recommended. Several different surgical options exist based on the degree of joint wear. The first, is to simply excise the arthritic bone (trapezium). This will eliminate the bones from rubbing on each other and alleviate pain. Another option is to replace one of the bones (trapezium) with an implant made of titanium or silicone. The third option, which tends to be the most preferred one, is to perform an arthroplasty of the thumb. In simplest form, this involves removing the arthritic joint surfaces and repositioning the surrounding tendons to better support the joint.
Following surgery, the thumb and hand is immobilized in a splint or cast for an extended period of time to allow healing. Full recovery from this type of procedure may take several months.