Effect of motion on digital nerve repair in a fresh cadaver model

Information in the literature regarding the postoperative management of digital nerve lacerations is vague, and postoperative immobilization for up to 3 weeks is frequently recommended. In order to define more precisely what, if any, postoperative restrictions are necessary, a fresh cadaver model was designed for digital nerve division, resection, repair, and passive motion. Ten digital nerves were divided at the proximal interphalangeal joint and then repaired, mobilized, and inspected. Intact nerve repairs were serially resected in order to determine the limits of resection that would allow motion without repair disruption. All repairs were resistant to disruption even with hyperextension up to a resection length of 2.5 mm, and all repairs were resistant to disruption if splinted in neutral up to a resection length of 5 mm. There was not 100 percent disruption of repairs until a resection length of 1 cm and range of motion including hyperextension. These results give valuable objective data that can be used to guide early motion and splinting protocols after various degrees of digital nerve injury and repair.