By Dr. Brent Steiner

Northwest Ohio Orthopedics & Sports Medicine

Our thumbs are one unique feature that separates us, as humans, from many other living creatures. Our thumbs are opposable, allowing us to grasp items and perform fine motor skills which would otherwise be impossible with a less mobile digit. 

The thumb is a complex structure providing multi-plane mobility and fine dexterity. The base of the thumb joint is described as a “saddle joint” due to its unique appearance and attachment structure.

A common problem related to the thumb is pain that develops at the base, making normal everyday activities challenging due to pain and loss of grip and pinch strength. Although there can be multiple causes for pain about the thumb and radial wrist, frequently this pain is caused by first carpometacarpal (CMC) osteoarthritis. 

In first CMC osteoarthritis, the cartilaginous surfaces at the base of the thumb (trapezium and first metacarpal) progressively deteriorate causing deformity, pain, instability and loss of grip and pinch strength.

This can lead to a significant decline in quality of life and can cause one’s independence with normal activities of daily living to suffer severely. Patients will often complain of a deep achy soreness along the base of the thumb which worsens with increased activity. Previous simple activities such as pulling up pants or socks, opening lids, turning doorknobs and grasping items with the thumb become exceedingly difficult. Another term for this condition is basilar thumb arthritis.

Basilar thumb arthritis will frequently present in the sixth decade of life but can be symptomatic in younger or older patients. In fact, up to 25% of males and 40% of females over the age of 75 will have basilar thumb arthritis. 

CMC arthritis can be diagnosed based on clinical symptoms and radiographic evaluation. Normally a simple in-office x-ray is the only imaging modality required to confirm the clinical diagnosis. Occasionally further imaging, such as MRI, can supplement the comprehensive workup in patients who may also have concomitant pathology within the surrounding carpal joints, gross instability or suspected tendon pathology. 

Treatment usually begins with nonoperative management such as bracing or wraps, anti-inflammatory medication, injections and/or therapy. For many patients, these relatively simple treatment options can keep symptoms tolerable for some time. 

If these modalities fail or become less effective, surgical options can be discussed. 

There are several surgical treatment options for CMC osteoarthritis, all of which involve removing or replacing the worn-out arthritic joint. Generally, surgical outcomes are favorable providing significant decrease in pain and significant subjective and objective improvement in stability, grip and pinch strength. The surgery is done on an outpatient basis, allowing patients to return home on the same day of surgery. 

Surgery can provide a profound improvement in quality of life, leading to decreased pain and improved function of the thumb.