What is a key feature of a saddle joint?

A key feature of a saddle joint is its unique structure that allows for a wide range of movement, particularly in two planes, which is characterized by the saddle-like shape of the articulating surfaces. This joint type permits flexion, extension, abduction, and adduction, enabling coordinated movements similar to how a rider would move while sitting on a horse. The specific interlocking nature of the bones contributes to this flexibility and stability.

While other joint types may allow for rotational movement, interlock, or be fixed, the distinction of a saddle joint lies in the unique morphology that permits multidirectional movement yet maintains a stable connection. Understanding saddle joints can be crucial in fields such as biomechanics, rehabilitation, and personal training, as they are involved in movements of critical importance, such as the thumb, which has a saddle joint allowing for a strong grip and fine motor skills.