Corpus: Middle phalanx
Definition
The term middle phalanx is used to describe the bones that form the middle phalanx of the fingers and toes, i.e., that connect distally to the proximal phalanx.
Anatomy
Fingers
The middle phalanx is longer than the distally following proximal phalanx, but shorter than the preceding proximal phalanx of the finger. The proximal end of the bones facing the proximal phalanx is larger and has a double concave articular cartilage with a sagittally aligned degree in the middle. Together with the cartilage surface of the proximal phalanx, it forms the metacarpophalangeal joint. The distal end ends in two small condyles that are separated by a sagittal groove. The thumb is the only finger without a middle phalanx, as it consists of only 2 phalanges.
Toes
The small, stunted-looking middle phalanges of the toes are longer than the distal phalanges. They are slightly wider in the middle section than the proximal phalanges of the toes and, in comparison, significantly shorter than the middle phalanges of the fingers.
The big toe is the only toe that does not have a phalanx media, as it consists of only 2 phalanges.
