Despite their small size, the phalanges are also classified as long bones. Therefore, each phalanx consists of the following three parts:

Base - expanded proximal end; the base of the proximal phalanx presents an oval-shaped concave articular surface, while the base of the intermediate phalanx and base of distal phalanx have double concavities that are separated by median ridges (sometimes these ridges are not very well pronounced);
Body or shaft - the middle or the central part of the phalanx that tapers distally; they are concave on the palmar surfaces while convex on the dorsal aspects (it is more visible for the proximal phalanges); the palmar aspects of the bodies are roughened, and they have raised ridges that mark attachment sites for the flexor sheaths;
Head - the expanded distal end of each phalanx; they are smaller than the bases; heads of the proximal and intermediate phalanges end in two condyles that form structures known as the trochleae, which articulate with the bases of the adjacent phalanges; the heads of the distal phalanges are called the distal tips.

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Phalanges of hand (parts)