Thumb Base Arthritis
Pain at the base of the thumb caused by wear of the carpometacarpal joint, often affecting pinch, grip and opening jars.
Common symptoms
Pain is usually felt where the thumb meets the wrist and may be triggered by opening jars, turning keys, pinching, writing or prolonged gripping. Swelling, reduced pinch strength and a sense of grinding can occur.
Why it happens
The thumb carpometacarpal joint is highly mobile and carries substantial load during pinch. Degenerative change can develop with age, ligament laxity, prior injury and individual anatomy.
How it is diagnosed
The clinician examines the thumb base, pinch and joint stability. X-rays can show joint-space narrowing, bone spurs and subchondral change, but treatment is guided by symptoms as well as imaging.
Treatment without surgery
Options may include activity modification, a supportive thumb splint, hand therapy, topical or oral pain medication when appropriate, and corticosteroid injection for selected patients.
When surgery is considered
Surgery may be considered when pain remains function-limiting despite a reasonable trial of non-operative treatment. Several procedures exist and the choice depends on age, activity level, joint pattern and surgeon assessment.
Recovery
Recovery from thumb-base surgery is measured in weeks to months. Splinting and hand therapy are often part of rehabilitation, and pinch strength may continue improving after pain has settled.