1st CMC (Carpometacarpal) arthritis is a common condition affecting the base of the thumb, where the thumb meets the wrist. It occurs when the cartilage at this joint wears down, leading to pain, stiffness, and reduced thumb function. This condition is especially common in older adults and can significantly impact daily activities such as gripping, pinching, or writing.

The 1st CMC joint is located at the base of the thumb and allows a wide range of motion, including pinching, gripping, and rotation. Arthritis in this joint develops when the cartilage that cushions the bones wears away, leading to bone-on-bone contact.

Age-related wear and tear (most common)

Repetitive thumb movements or overuse

Previous injuries or fractures of the thumb

Genetic factors that predispose individuals to joint degeneration

Hormonal influences, especially in postmenopausal women

Pain at the base of the thumb, worsening with activity

Swelling and tenderness around the joint

Reduced strength for gripping or pinching objects

Difficulty performing daily tasks like opening jars or turning keys

Stiffness, especially in the morning

Possible formation of a small bump or deformity at the joint

Activity modification – avoiding movements that trigger pain

Splints or braces to support and stabilize the thumb

Pain relief medications such as NSAIDs

Corticosteroid injections to reduce inflammation

Physiotherapy to strengthen muscles around the thumb and improve range of motion

Trapeziectomy – removal of the trapezium bone in the thumb base

Ligament reconstruction with tendon interposition (LRTI) – stabilizes the thumb after bone removal

Thumb joint replacement (arthroplasty) – replaces the damaged joint with a prosthesis

Arthrodesis (fusion) – fuses bones to reduce pain in severe cases

Non-surgical treatments may provide relief within weeks to months.

Surgical recovery typically takes 6–12 weeks, with gradual physiotherapy for restoring motion and strength.

Long-term exercises and precautions are essential to prevent recurrence and maintain hand function.

Avoid repetitive stress on the thumb

Use ergonomic tools and adaptive devices for daily activities

Perform hand exercises to maintain flexibility and strength

Early medical consultation for persistent thumb pain