Each finger except the thumb consists of three bones – the proximal, middle, and distal phalanx. The thumb has only two phalanges – the proximal and the distal.
The list of terms:
Phalanx proximalis – Proximal phalanxPhalanx media – Middle phalanx
Phalanx distalis – Distal phalanx
Caput phalangis – Head of the phalanx
Trochlea phalangis – Trochlea of phalanx
Corpus phalangis – Body (shaft) of phalanx
Basis phalangis – Base of phalanx
Tuberositas phalangis distalis – Tuberosity of distal phalanx
Click an image to switch between the top- and bottom-oblique view. Note the shape of the congruent articular surfaces between phalanges (uniaxial, hinge-type joint). It differs from the ellipsoid-shaped metacarpophalangeal joint, providing bi-axial rotation of the proximal phalanx. The shape of the articular surface at the base (ellipsoid vs. bi-concave) is the main characteristic allowing to differentiate the proximal phalanx from the distal one.
Last update: 20/Dec/2020