Corpus: Proximal phalanx
Definition
The term proximal phalanx refers to the bones that constitute the base member of the fingers and toes, directly adjoining the metacarpal bones (hand) or metatarsal bones (foot).
Anatomy
Fingers
The proximal phalanx is longer than the distally following phalanges. The extremity of the bone facing the metacarpal bones, the proximal extremity, has a concave articular cartilage, which is more extensive in the frontal direction than in the sagittal. It forms with the cartilage surface of the respective metacarpal bone the metacarpophalangeal joint (base joint of the finger).
Toes
The proximal phalanx is longer than the distal phalanges of the toes. The proximal extremitas of the bones facing the metatarsal bones has concave articular cartilage. Together with the cartilage surface of the respective metatarsal bone, it forms the articulatio metatarsophalangealis (metatarsophalangeal joint). The metatarsal phalanges of the toes are significantly shorter than those of the fingers and have a compact, biconcave basic shape when viewed from above.
