CMCgewrichten

The carpometacarpal (CMC) joints are a group of five articulations located at the base of the hand, where the metacarpal bones of the palm meet the carpal bones of the wrist. Specifically, there are five CMC joints, each corresponding to one of the metacarpal bones. The most significant and commonly discussed CMC joint is the first CMC joint, also known as the carpometacarpal joint of the thumb. This joint is formed between the trapezium carpal bone and the base of the first metacarpal bone. The other four CMC joints (digits 2 through 5) are formed by the articulation of the remaining metacarpals with the trapezoid, capitate, and hamate carpal bones, respectively.

The CMC joints, particularly the thumb's CMC joint, are crucial for hand function. The first CMC joint is a saddle joint, allowing for a wide range of motion, including flexion, extension, abduction, adduction, and opposition. This unique structure enables the thumb to perform complex movements, such as grasping and pinching, which are essential for fine motor skills and everyday activities. The other four CMC joints are more planar in nature and offer limited gliding movements, primarily contributing to the stability and overall shape of the hand.

Conditions affecting the CMC joints can significantly impact hand function. Osteoarthritis is a common degenerative joint disease that frequently affects the first CMC joint, leading to pain, stiffness, and reduced grip strength. Other conditions include inflammation, trauma, and congenital abnormalities. Treatment approaches for CMC joint issues vary depending on the severity and type of condition and can range from conservative management like rest, splinting, and medication to surgical interventions such as joint fusion or replacement.