Flexor digitorum profundus avulsion with associated fracture of the distal phalanx

Two unusual cases of flexor digitorum profundus avulsion with an associated fracture of the distal phalanx are reported. In one case the injury consisted of avulsion of a large bone fragment from the distal phalanx and an associated profundus avulsion from the fragment. The other case showed simultaneous shaft fracture of the distal phalanx with avulsion of the profundus tendon, which could not be included in the existing classification of profundus injuries. The latter injury was misdiagnosed initially.