Intraarticular fractures of the proximal phalanx of the thumb must be treated radically to avoid
loss of motion
Articular congruity should be restored anatomically. In cases of comminuted impacted fractures (“pilon”), bone graft from the distal radius is needed to fill the metaphyseal defect resulting from elevation of the depressed fragments.
It is difficult to assess the extent of articular comminution from plain radiographs. A CT scan is advisable.
Choice of approach
In the case of extension of the fracture into the diaphysis, the dorsal approach to the MCP joint is modified so that the distal incision extends as far as the interphalangeal (IP) joint. The IP joint itself will not be opened. Be careful not to detach the insertion of the extensor pollicis brevis (EPB) into one of the basal fragments.