About thumb (CMC) arthritis
The carpometacarpal (CMC) joint sits where the thumb meets the wrist. Its saddle shape lets the thumb swing across the palm, which is what makes pinching and gripping possible. That same freedom of motion puts a lot of stress on the joint over a lifetime.
In CMC arthritis, the smooth cartilage lining the joint wears thin and the ligaments that hold it steady loosen. The joint can shift slightly out of line, which makes pinching painful and weaker. It is one of the most common places in the hand for arthritis, and it is especially common in women after midlife.
Common symptoms
- Aching at the base of the thumb, near the wrist
- Pain with pinching, writing, turning keys, or opening jars
- A weaker pinch or grip
- Swelling or a bump at the base of the thumb
- Stiffness, and in later stages a thumb that is harder to open wide
Common causes and risk factors
- Age-related wear on the joint
- Looser ligaments, which let the joint shift under load
- An old fracture or injury at the base of the thumb
- Repetitive pinching and gripping over many years
- Family history
How we diagnose it
We examine the thumb for tenderness, grinding, and instability, and we check nearby areas such as the wrist tendons that can cause similar pain. Ultrasound at the exam table shows joint swelling, bone spurs, and how the joint moves under load. X-rays help stage the arthritis when that will change the plan.
How Propel treats thumb (CMC) arthritis
Conservative care comes first and often works well. A custom or off-the-shelf thumb splint can calm a flare, and a targeted strengthening program for the muscles that stabilize the thumb helps many people pinch with less pain. We also look at tools and grip changes that reduce strain while keeping you active in the things you enjoy.
When pain persists, an ultrasound-guided injection places medicine precisely inside this small joint. Some people consider PRP, a concentrate from their own blood, to ease pain and improve function. PRP does not rebuild cartilage, and evidence in the thumb is still growing. For advanced arthritis that no longer responds to these options, we help coordinate referral to a hand surgeon.
What to expect at your visit
- 1.
We listen first
Your visit opens with a real conversation: how the problem started, what you have already tried, and the activity you want back.
- 2.
Exam and in-office ultrasound
A hands-on exam, then ultrasound at the exam table, often while you move, so your physician can see the tendon, joint, or nerve involved.
- 3.
A clear diagnosis and plan
You leave knowing what is wrong and what your options are, from strength-based rehab to procedures, and why we recommend each one.
- 4.
Treatment and follow-through
Most procedures happen here in the office. We coordinate with your physical therapist and check progress against the goals you set.
Questions about thumb (CMC) arthritis
- Should I wear a thumb brace all the time?
- A brace is most helpful during flares and during activities that aggravate the thumb. Wearing it constantly can let the supporting muscles weaken, so we pair bracing with strengthening. Your physician will suggest a schedule that fits your day.
- Why is my thumb injection done with ultrasound?
- The thumb CMC joint is small and surrounded by tendons and a nerve branch. Ultrasound lets our physicians see the needle enter the joint, which improves accuracy and helps avoid nearby structures.
- Will exercise make thumb arthritis worse?
- The right exercises usually help. Strengthening the muscles around the base of the thumb supports the joint and can reduce pain with daily tasks. We guide you on which movements to build up and which to modify during a flare.