What motions are produced at the interphalangeal joints?

The interphalangeal joints, found in the fingers and toes, primarily allow for movements of flexion and extension. This means that these joints enable the bending (flexion) and straightening (extension) of the digits.

Flexion occurs when the angle between the phalanges decreases, typically bringing the fingers or toes closer together. Extension is the opposite, where the angle increases, allowing the digits to straighten out. The unique anatomy of the interphalangeal joints, which are classified as hinge joints, restricts them to these two specific motions primarily, ensuring functional flexibility for grasping and manipulating objects in the hands and providing stability in the feet during walking and running.

Other types of motions, such as abduction and adduction, typically occur at the metacarpophalangeal joints rather than the interphalangeal joints. Inversion and eversion pertain to the movements of the foot at the ankle, while dorsiflexion and plantar flexion relate to the ankle joint and the motions of moving the foot up or down. Therefore, it is clear that flexion and extension are the correct answers for the motions produced at the interphalangeal joints.