Thumb Arthritis: What to Know

Symptoms, when to be seen, and your treatment options

If opening a jar or turning a key has started to hurt at the base of your thumb, you may have arthritis of the CMC joint. It is one of the most common conditions we treat, and one of the most treatable. Most people never need surgery.

What it is

The CMC (basal) joint sits where your thumb meets your wrist. Its saddle shape is what gives the thumb a significant amount of range of motion, which also wears it out quicker. Every pound of pinch at your fingertip becomes 12 pounds of pressure at the base of the thumb.

It is common, especially in women, and usually starts in the 40s and 50s. On X-ray, thumb base arthritis appears in about 7% of 50-year-old women and nearly 40% of women in their 80s. The X-ray changes often show up long before any pain — so we treat the patient, not the film.

Symptoms

• Pain at the base of the thumb, on the palm side near the wrist
• Pain with pinching and gripping — jars, keys, doorknobs, buttons, wringing out a cloth, texting
• An ache that lingers for hours after a busy day, sometimes worse at night
• Weakness — dropping cups, needing two hands for one-handed tasks
• Grinding, swelling, or a squared-off bump at the base of the thumb as the joint shifts

Later on, the thumb may sit closer to the palm and you may not be able to open your hand wide enough to grab a large glass. The adjacent joint (MCP) can become unstable and end up with an hyperextension deformity.

When to come in

Come in if thumb pain has limited your daily activities for more than a few weeks, a drugstore brace and rest are not holding you, you are losing grip strength or dropping things, pain wakes you at night, or the shape of your thumb is changing. The visit will typically include a history, an exam, and X-rays. An MRI is almost never needed.

Treatment without surgery

• Activity changes. Fatter grips on pens and tools, an electric jar opener, a key turner, carrying bags on your forearm instead of pinched in your fingers, and breaking up long pinching tasks.
• Bracing. Thumb brace reduces pain, and rigid braces supporting both the CMC joint and thumb knuckle worked best. I usually recommend wearing one during aggravating activities rather than all day.
• Hand therapy and topicals. A certified hand therapist can fit a custom orthosis and teach joint protection. Topical anti-inflammatory gels (Voltaren) work well here because the joint sits close to the skin.
• Steroid injection. Many patients get several months of relief, and a good response confirms the joint is the pain source. The evidence is mixed — one placebo-controlled trial found no benefit at six months in advanced arthritis — and the effect tends to be better in earlier-stage disease. Worth trying, not worth repeating indefinitely.

Surgical options

Surgery is elective and appropriate when pain persists despite an honest nonoperative trial. Waiting does not burn any bridges.

• Denervation. The newest of these options in US practice, and increasingly popular over the last three to five years. Rather than removing or replacing the joint, we divide the tiny sensory nerves that carry pain from the joint capsule. The arthritis stays put, but stops hurting. It is a shorter operation, requires no lengthy cast, and returns you to activity in weeks rather than months — and because no bone is removed, a trapeziectomy remains fully available later. Thumb CMC joint denervation reliably reduces pain and improves function, with outcomes comparable to trapeziectomy-based procedures in the short-to-medium term, and faster recovery. There are certain percentages of patients who will need conversion to trapeziectomy.
• Trapeziectomy. The reference standard, and the option with the longest track record. We remove the arthritic wrist bone (the trapezium); the space fills with scar tissue and the thumb settles into a stable position. In a review of 22 studies and more than 800 thumbs followed an average of 8.3 years — some past 20 — satisfaction averaged 91%, grip strength improved about 25%, and reoperation rates ran around 1% for simple trapeziectomy. The trade-off is recovery: a splint or cast for two to six weeks, light activity around four to six weeks, and strength returning gradually — roughly 40% of your eventual function at three months, 80% at six, plateauing near nine months.
• Implants and joint replacement. The joint is resurfaced with a small implant instead of removed. Recovery is faster and early pinch strength may be better, and modern implants report 80–95% survival at 10 years. I do not usually recommend it: revision rates run 5–20% at medium-term follow-up versus under 5% for trapeziectomy, and matched studies show implant patients are about 2.5 times more likely to need another operation. When an implant fails, the salvage surgery is harder because of bone loss. Thoughtful surgeons disagree with me on this, and if a fast return to work is your priority it is a fair conversation to have.

The bottom line

There is no single best treatment — there is a best treatment for you, based on how much the thumb bothers you, how much recovery time you can absorb, and what your hands need to do. Early arthritis usually responds well to bracing and activity changes. If pain is the main problem and you want to be functional quickly, denervation is an appealing option. If the joint is significantly worn or you want the most durable answer, trapeziectomy is the most predictable.

Either way, the outlook is good. Thumb arthritis is a nuisance, not a threat, and nearly everyone ends up with a hand that works well for what they want to do. If your thumb has been limiting you, come in and let’s take a look.