Head, intraarticular

Metacarpal head fractures may be simple, but are often multifragmentary. The degree of displacement and the number of fragments may be difficult to judge on standard x-rays. CT scans can be helpful in these situations.

The fractures can usually be treated with screw fixation, but require skill and experience. If the fragments are sufficiently large, screws are inserted in an antegrade manner, without perforating the articular cartilage. In smaller fragments, retrograde fixation has to be performed, and the screws are inserted through the articular cartilage. Care must be taken to bury the screw head underneath the cartilage. As an alternative to standard screws, small headless screws can be used if the fragment is sufficiently thick. In severely impacted fractures, bone graft, harvested from the distal radius, may be necessary.