Which type of joint is found between the thumb metacarpal and the wrist?

The joint found between the thumb metacarpal and the wrist is classified as a saddle joint. This type of joint is characterized by its unique shape, allowing for a greater range of motion than hinge or pivot joints. Specifically, the saddle joint can move in two planes: it allows flexion and extension as well as abduction and adduction, which are critical for the thumb's functionality, especially in grasping and pinching movements.

The structure of the saddle joint facilitates the opposition of the thumb, a crucial feature that distinguishes human hand function, enabling a strong grip and dexterity. The articulation occurs between the trapezium bone of the wrist and the first metacarpal of the thumb, supporting these varied movements.

While the other types of joints have their specific motions (hinge joints allow for movement in one plane, pivot joints facilitate rotational movement, and ball-and-socket joints provide a broad range of motion in multiple directions), they do not offer the unique combination of movements provided by a saddle joint, making it an essential element of thumb mobility and hand function.