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, and a small one laterally for the capitate.
On the radial side are two oval facets, for articulation with the third metacarpal; and on the ulnar side a single concave facet, for the fifth metacarpal.
Clinical relevance A shortened fourth metacarpal bone can be a symptom of Kallmann syndrome, a genetic condition which results in the failure to commence or the non-completion of puberty. A short fourth metacarpal bone can also be found in Turner syndrome, a disorder involving sex chromosomes.
A fracture of the fourth and/or fifth metacarpal bones 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.
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See also Metacarpus First metacarpal bone Second metacarpal bone Third metacarpal bone Fifth metacarpal bone
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