What type of joint is the knee?

The knee is classified as a hinge joint, which is characterized by its ability to primarily allow movement in one plane—specifically, flexion and extension. This type of joint is similar to the action of a hinge on a door, enabling the knee to bend and straighten effectively.

The structure of the knee involves the femur (thigh bone) and the tibia (shin bone), with the joint supported by ligaments and cartilage that facilitate movement while providing stability. The hinge design allows for a wide range of motion during activities such as walking, running, and jumping, often emphasizing the flexion and extension movements of the leg.

Understanding the functional characteristics of hinge joints is vital in fitness and rehabilitation contexts, as this knowledge informs exercises that can promote knee health and strength. This specific joint structure also distinguishes the knee from types like ball and socket joints, which allow for a greater range of motion in multiple directions, or pivot joints, which enable rotation around a single axis.