The MCP joints, or metacarpophalangeal joints, are the connections between the metacarpal bones of the hand and the proximal phalanges of the fingers. These joints allow for a wide range of motion, including flexion, extension, abduction, and adduction, enabling the fingers to grasp and manipulate objects effectively. Each MCP joint is surrounded by a capsule and supported by ligaments that provide stability. They play a crucial role in hand function and are essential for activities such as writing, typing, and playing musical instruments. Proper functioning of the MCP joints is vital for overall hand health and dexterity.