Metacarpal Base Fractures
(Green 7e) The hamate articulates with the ring and small metacarpals by two concave facets separated by a ridge. The base of the 5th metacarpal consists of a concave-convex facet that articulates with the hamate and a flat radial facet that articulates with the fourth metacarpal base.
- CMC ligaments
- Interosseous ligament
- 4th & 5th – less stable than 2nd & 3rd (increased CMC joint mobility)
- Motor branch of ulnar nerve runs in close proximity with 4th & 5th metacarpal bases
(Green 7e) There is no consensus regarding optimal treatment of these fractures. Options run the gamut from closed reduction and cast immobilization to ORIF.
Bora and Didizian found that weakness of grip was the major functional disability resulting from inadequate reduction or lost reduction. These authors recommended closed reduction and percutaneous pin fixation of the 5th metacarpal to the 4th metacarpal or carpus for maintenance of reduction.