Why do you think that hinge joints only bend in one direction?

Hinge joints are designed to allow movement in one specific plane, resembling the mechanism of a door hinge. This unique structure, formed by articular surfaces that fit together in a way that restricts movement, ensures stability and efficient load-bearing in activities like walking and lifting. The unidirectional bending minimizes the risk of injuries, as it limits excessive motion that could lead to dislocation or strain. Overall, this design optimizes both functionality and safety in joint movement.