Accuracy in Screw Selection in a Cadaveric, Small-Bone Fracture Model

Using a cadaveric model simulating clinical situations experienced during open reduction and internal fixation of proximal phalangeal fractures, the aim of this study was to evaluate the relationship between level of training and the rates of short, long, and ideal screw length selection based on depth gauge use without fluoroscopy assistance.

A dorsal approach to the proximal phalanx was performed on the index, middle, and ring fingers of 4 cadaveric specimens, and 3 drill holes were placed in each phalanx. Volunteers at different levels of training then measured the drill holes with a depth gauge and selected appropriate screw sizes. The rates of short, long, and ideal screw selection were compared between groups based on level of training. Ideal screws were defined as a screw that reached the volar cortex but did not protrude more than 1 mm beyond it.

Eighteen participants including 3 hand fellowship-trained attending physicians participated for a total of 648 selected screws. The overall rate of ideal screw selection was lower than expected at 49.2%. There was not a statistically significant relationship between rate of ideal screw selection and higher levels of training. Attending surgeons were less likely to place short screws and screws protruding 2 mm or more beyond the volar cortex CONCLUSIONS: Overall, the rate of ideal screw selection was lower than expected. The most experienced surgeons were less likely to place short and excessively long screws.

Based on the low rate of ideal screws, the authors recommend against overreliance on depth gauging alone when placing screws during surgery. The low-rate ideal screw length selection highlights the potential for future research and development of more accurate technologies to be used in screw selection.