Abstract
We report two cases of rotationally displaced unicondylar fracture of the basal phalanx. The first patient was an 18-year-old man with a unicondylar fracture of the right litte finger in which the fragment was supinately displaced. The fracture, sustained when catching a softball two days before the first visit, caused pain and limited the range of motion of the finger. Open reduction and internal fixation with two Kirschner wires were performed. Good reduction was obtained and early active motion was started. Six months after the operation, extension of the PIP joint was -20°, and flexion was 105°. The second patient was a 70-year-old man with a unicondylar fracture of the right index finger in which the fragment was pronately displaced. He had injured the finger when using a sanding machine, and visited us soon afterwards. An open wound was present on the dorsal aspect of the PIP joint. We inserted a small elevator into the wound and reduced the fragment. The fragment was stable, and early active motion was started. Seven months after the operation, extension of the PIP joint was -20°, and flexion was 90°.
We consider that lateral and rotational stress imposed at the same time cause rotationally displaced unicondylar fracture of the basal phalanx. To obtain better extension of the PIP joint, passive motion should be started early.
