What is Thumb Arthritis?

Thumb arthritis, also known as basal joint arthritis, is the degeneration of the thumb joint at the base of the thumb metacarpal. Thumb arthritis is usually found in the trapezium/metacarpal joint (TMC), but it can be present in the joint below the TMC as well. It is the second most common form of arthritis in the hand, surpassed only by arthritis in the last joint of each finger.

Symptoms & Causes

The most common symptom of thumb arthritis is pain at the junction of the thumb and the wrist, which is exacerbated by pinching, or flexing, those bones together. Many times there is deformity of the wrist, including loss of the web space between the thumb and index finger. Swelling and stiffness of the joint are also common symptoms of basal joint arthritis.

Affected Populations

Basal joint arthritis of the thumb is extremely common. It usually occurs in women over the age of 45, or men over the age of 60. It can be isolated to the thumb alone or be present alongside other hand and/or wrist arthritis. Often, patients will present with a family history of arthritis. While the condition itself is not work-related, doing any job will be hard with thumb arthritis. While osteoarthritis is the biggest culprit, there are other conditions such as inflammatory arthritis that can affect the base of the thumb and cause the deterioration of that joint. In rare cases, an old fracture can lead to thumb arthritis.


Treating thumb arthritis is about controlling pain. Thumb arthritis has usually progressed for years before anyone seeks treatment. There is no prevention or preventative treatment for arthritis. In addition, there is no benefit to early surgical intervention. Initial treatments consist of bracing and periodic steroid injections. No exercise program has been shown to slow the progression of thumb arthritis. When bracing and steroid injections no longer help, surgical treatment can be very successful. The patient makes the decision to operate. The trapezium is removed, and a tendon is usually placed in the space that once held the trapezium. The deformity is usually corrected at the time of surgery. If a patient has a significant “Z” deformity, they may require a fusion or a stabilization of the joint above is required.

Thumb Arthritis Arthritic Joint

Thumb Arthritis

Additional Resources