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CMC Arthritis

thumb arthritis graphic

Ever heard of CMC Arthritis, or perhaps Carpometacarpal?

What is arthritis at the base of the thumb?

Osteoarthritis occurs when there is a loss of joint space between two bones. One of the most common joints in the hand to develop osteoarthritis is at the base of the thumb. Due to the normal mobility of this joint, it is prone to wear and tear, which results in loss of the cartilage or cushion between the joint. Arthritis at the base of the thumb is also known as CMC arthritis or basal joint arthritis.

What causes arthritis at the base of the thumb?

The cause of arthritis at the base of the thumb is thought to be the result of a combination of factors including family history, repetitive pinching or twisting of the thumb and general overuse. Thumb arthritis can also occur when there is a history of trauma, fractures or dislocations of the thumb. Thumb arthritis is seen most often in females over the age of 50.

What are the symptoms of thumb arthritis?

The symptoms of basal joint arthritis are pain with pinching, gripping and general thumb use. Using a key, turning a door knob or opening a jar can be painful with this type of arthritis. Thumb pain may also occur at night or when resting. Individuals with arthritis at the base of the thumb may also notice swelling at the area of pain.

What is the treatment for arthritis at the base of the thumb?

Treatment for basal joint arthritis can be nonoperative or operative. The initial conservative treatment is rest and modification of daily activities. If the symptoms are mild, the physician may prescribe an anti-inflammatory medicine, a referral to a hand therapist and/or suggest a cortisone injection to help decrease the pain. If the symptoms persist and begin to limit hand function, the physician may recommend surgery.

To meet with one of our specialists contact BoulderCentre (303) 449-2730 and ask for Dr. Daniel Master.


“Working with a knowledgeable hand therapist can make the difference between success and failure in complex hand surgical cases. The therapist extends the continuum of our care, as well as functioning as coach and trainer for our patients.”

~ Marybeth Ezaki, MD, President, American Society for Surgery of the Hand


How can a hand therapist help with arthritis at the base of the thumb?

Initially, a hand therapist can provide patient education including use of adaptive equipment, activity modification and special exercises to help reduce pain. A hand therapist can also provide a custom-fabricated brace or orthosis that will allow the thumb joint to rest and will provide support while performing daily activities. Hand therapy following surgery improves range of motion, and teaches the patient how to regain the function of the hand.

Contact BoulderCentre (303) 449-2730 for your hand therapy appointment with one of our specialists Sally Brown, Bridget Myers or Charla Stilling.

See all of BoulderCentre’s Physical Therapists.

Content courtesy of American Society of Hand Therapists.