Quick Facts
Location: Hand.
Bone Type: Long Bone.
Key Features: Head, body, base, medial and lateral surfaces, and proximal and distal articular facets.
Articulates With: Proximal phalanx of little finger, hamate, and fourth metacarpal bone.
Arterial Supply: Palmar metacarpal arteries.
Related parts of the anatomy
Key Features & Anatomical Relations
The fifth metacarpal bone is one of the five metacarpal bones of the hand. It’s classified as a long bone and includes the following bony features:
- parts: head, body, and base;
- surfaces: medial and lateral surfaces;
- landmarks: proximal and distal articular facets.
More information regarding these bony features can be found in the Parts, Surfaces and Landmarks tabs for this bone.
The fifth metacarpal bone is located:
- proximal to the proximal phalanx of little finger;
- distal to the hamate bone;
- medial to the fourth metacarpal bone.
It articulates with the:
- proximal phalanx of little finger at the fifth metacarpophalangeal joint;
- hamate bone, contributing to the formation of the carpometacarpal joints;
- fourth metacarpal bone, contributing to the formation of the intermetacarpal joints.
Ossification
Ossification of the fifth metacarpal bone occurs at two ossification centers, these are found in the:
- body, which appears in utero at the ninth week;
- head, which appears within the second to third years.
These ossification centers fuse with each other during the fifteenth to nineteenth years (Standring, 2016).
Variations
The base of the fifth metacarpal bone can vary between individuals in terms of the number and size of its articular surfaces.
Surface Anatomy
The following bony features of the fifth metacarpal bone are relevant to surface anatomy:
- the head can be palpated at the “knuckle” that is proximal to the proximal phalanx of the little finger, particularly during flexion of the fifth metacarpophalangeal joint;
- the body and base can be palpated along the medial aspect of the hand.
List of Clinical Correlates
- Fracture of fifth metacarpal bone (base or body)
- Boxer’s fracture of fifth metacarpal bone
- Reverse Bennet’s fracture or dislocation
- Mauclaire’s disease
References
Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edn.: Elsevier Limited.
Learn more about this topic from other Elsevier products
Metacarpal Bone
The trapezial angle is defined the complement of the angle formed by the intersection of the line parallel to the trapezial articulation and the line parallel to the long axis of the index metacarpal bone.
