Finger middle and end joints
The finger middle and end joints (Articulationes interphalangeales) connect the individual phalanges. They are hinge joints, both anatomically and functionally. Movements in one plane (flexion and extension) are therefore possible.
These finger joints are also surrounded by a very taut capsule reinforced by a tendon plate. All fingers, with the exception of the thumb, have a finger middle joint (proximal finger joint, PIP) and a finger end joint (distal finger joint, DIP). In the fingers themselves, no muscles of their own can be found, but only ligaments and tendons originating from the hand and forearm muscles. With the exception of the thumb, all fingers have two long tendons from the muscles of the forearm, one each for bending and stretching.