Rhizarthrosis

Osteoarthritis localized at the base of a finger or limb. In practice, the term is reserved for thumb osteoarthritis, a condition that affects the joint between the trapezium (a bone in the wrist) and the first metacarpal (a bone in the hand), primarily involved in thumb opposition movements (pinching between the thumb and index finger). Rhizarthrosis is typically bilateral and is more common in individuals who use their thumbs intensively (such as waiters, goldsmiths, and athletes). It manifests with pain and stiffness, and in advanced stages, it may also cause deformities (such as a Z-shaped thumb).