Head of the metacarpals

Study entry

Description

The distal end of each metacarpal.

Relations

Articulates with the proximal phalanx; the heads form the knuckles.

Palpation

The knuckles of the closed fist; that of the 3rd is the most prominent.

Source: cap. 3, «Huesos de la mano» y «Anatomía de superficie de los huesos del miembro superior»

Clinical correlation

Fractures of the metacarpals; boxer's fracture

From the 2nd to the 5th, the metacarpals are attached to one another, so an isolated fracture is usually stable, and because they are well supplied with blood they heal quickly. An oblique (spiral) fracture may overlap or rotate the distal fragment, shortening the finger or making it flex out of alignment. Crushing may break several and leave the hand unstable. The fracture of the 5th metacarpal, the "boxer's fracture", happens when an untrained person throws a punch with a closed, abducted fist: the head rotates on the shaft and is left flexed.

Related clinical cases

• Fractures of the metacarpals; boxer's fracture

Other structures in this region

• Conoid tubercle
• Trapezoid line
• Scapular notch
• Glenoid cavity
• Supraglenoid tubercle
• Infraglenoid tubercle
• Subscapular fossa
• Supraspinous fossa