The thumb CMC joint has been reported as the most painful joint when compared to other hand joints affected by OA. It is therefore no surprise that this is a common chief complaint of patients and has a significant effect on work and life satisfaction Patients often present with complaints of pain localized to the base of the thumb that is exacerbated when performing tasks such as opening a jar, turning a car key, and turning door Knob, this pain may be reproduced by resisted pinch and grip .~On physical examination, patients will have point tenderness at the thumb basal joint with swelling and crepitus when the basal joint is compressed - a positive grind test and a positive hump sign from dorsal CMC dislocation subluxation .
The basal joint, also referred to as the carpometacarpal (CMC) joint, of the thumb is one of the joints most commonly affected by arthritis. CMC joint arthritis can lead to decreased grip and pinch strength and impairment of activities of daily living