Finger bones

The phalanges are two on the thumb and three on the other fingers.

Phalanx
On each article we distinguish 3 main parts:


 * basis phalangis – wider proximal section, base of the article;
 * corpus phalangis – slimmer body of the cell, middle part;
 * caput phalangis – the head with which the article ends distally.

The bases of the phalanges are transversely widened, proximally bearing an oval concave articular facet for connection with the corresponding bone of the metatarsus. For middle and distal segments, pulleys with a guide rail support the well.

The bodies of the phalanges resemble the phalanges on the hand only in the proximal phalanges, the bodies of the other phalanges are usually very short.

The phalanges heads have convex pulleys with a groove (similar to the hand).

Phalanx proximalis, media, distalis
According to the position on the finger, the phalanx proximalis, media et distalis is recognized. The thumb does not have phalanx media.

The proximal phalanges are slender(except for the thumb). The middle and distal segments are short (especially the middle cells) and tend to merge with the distal phalanx.

Distal segments have tuberositas phalangis distalis at the ends on the plantar side – roughness for attachment of the ligament of the fingertip (similarly as on the hand).

Tangible
Palpable are the phalanges of the fingers from the dorsal side.

Ossa sesamoidea pedis – sesamoid bones of the leg

 * They occur in a pair at the metatarsophalang joint of the thumb.
 * They are oval bones embedded in the tendons of the short muscles of the thumb.
 * Contact with the joint is conditioned by two grooves on the head of the thumb metatarsal bone.
 * A similar pair of sesame bones is often under the metatarsophangang joint of the 2nd and 5th fingers, rarely in the 3rd or 4th finger.
 * The sesame bone is also common in the tendon of m. fibularis longus – where the tendon curves under the os cuboideum (sesamum fibulare).

Related articles

 * Bones of the fingers
 * Joints of the foot