Comminuted fractures often result from crushing or high-energy injuries and may involve several metacarpals. Compartment syndrome may occur with these types of injuries, and fasciotomy may therefore be necessary. These fractures tend to be very unstable.
Bridge plating uses the plate as an extramedullary splint fixed to the two main fragments, while the complex fracture zone is bridged, thereby restoring axial alignment, length and correct rotational alignment of the main shaft fragments. The dissection required to reduce anatomically all the intermediate fragments would risk disturbing their blood supply and is not necessary. If the soft-tissue attachments of these fragments are preserved, and they are relatively well aligned, healing is predictable. Occasionally, a larger wedge fragment can be fixed to one of the main fragments using a lag screw. Relative mechanical stability, provided by the bridging plate, leads to healing by callus formation.
Multiple metacarpal fractures
When multiple metacarpals are injured, restoration of length and rotation is difficult. If one of the finger metacarpals is intact, the fixation is started on the adjacent metacarpal, and then continued sequentially. With one incision it is possible to fix two metacarpals.
Fix two metacarpals
If all four metacarpals are fractured, fixation is started with the least comminuted, and then the adjacent metacarpals are fixed.