The fourth metacarpal bone (metacarpal bone of the ring finger) is shorter and smaller than the third. The base is small and quadrilateral; its superior surface presents two facets, a large one medially for articulation with the

hamate The hamate bone (from Latin hamatus, "hooked"), or unciform bone (from Latin ''uncus'', "hook"), Latin os hamatum and occasionally abbreviated as just hamatum, is a bone in the human wrist readily distinguishable by its wedge shape and a hook-l ...

, and a small one laterally for the

capitate The capitate bone is a bone in the human wrist found in the center of the carpal bone region, located at the distal end of the radius and ulna bones. It articulates with the third metacarpal bone (the middle finger) and forms the third carpomet ...

. On the radial side are two oval facets, for articulation with the

third metacarpal The third metacarpal bone (metacarpal bone of the middle finger) is a little smaller than the second. The dorsal aspect of its base presents on its radial side a pyramidal eminence, the styloid process, which extends upward behind the capitate; ...

; and on the ulnar side a single concave facet, for the

fifth metacarpal The fifth metacarpal bone (metacarpal bone of the little finger or pinky finger) is the most medial and second-shortest of the metacarpal bones. Surfaces It presents on its base one facet on its superior surface, which is concavo-convex and artic ...

Clinical relevance

A shortened fourth metacarpal bone can be a symptom of

Kallmann syndrome Kallmann syndrome (KS) is a genetic disorder that prevents a person from starting or fully completing puberty. Kallmann syndrome is a form of a group of conditions termed hypogonadotropic hypogonadism. To distinguish it from other forms of hypog ...

, a genetic condition which results in the failure to commence or the non-completion of

puberty Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a girl, the testes in a bo ...

. A short fourth metacarpal bone can also be found in

Turner syndrome Turner syndrome (TS), also known as 45,X, or 45,X0, is a genetic condition in which a female is partially or completely missing an X chromosome. Signs and symptoms vary among those affected. Often, a short and webbed neck, low-set ears, low hair ...

, a disorder involving sex chromosomes. A fracture of the fourth and/or

fifth metacarpal bone The fifth metacarpal bone (metacarpal bone of the little finger or pinky finger) is the most medial and second-shortest of the metacarpal bones. Surfaces It presents on its base one facet on its superior surface, which is concavo-convex and artic ...

s transverse neck secondary due to axial loading is known as a boxer's fracture.Shultz, S. J., Houglum, P. A., Perrin, D. H. (2010). Examination of Musculoskeletal Injuries. Chicago: Human Kinetics

Ossification

The ossification process begins in the shaft during prenatal life, and in the head between 11th and 37th months.

Additional images

File:Fourth metacarpal bone (left hand) - animation01.gif, Fourth metacarpal bone of the left hand (shown in red). Animation. File:Fourth metacarpal bone (left hand) - animation02.gif, Fourth metacarpal bone of the left hand. Close up. File:Gray219 - Fourth metacarpal bone.png, Palmar view of the left hand (fourth metacarpal shown in yellow). File:Gray220 - Fourth metacarpal bone.png, Dorsal view of the left hand (fourth metacarpal shown in yellow). File:Neck Fracture of the Fourth Metacarpal Bone.png, A fractured right hand fourth metacarpal ( boxer's fracture).

References

Skeletal system Bones of the hand Metacarpus {{Portal bar, Anatomy

Clinical relevance

Ossification

Additional images

See also

References