IMPORTANCE OF CROSSOVER INNERVATION IN DIGITAL NERVE REPAIR DEMONSTRATED BY NERVE ISOLATION TECHNIQUE

This study was conducted to determine how testing of nerve repair usin g nerve isolation techniques compares with standard testing. Nerve iso lation consisted of double-gloving, leaving the study finger free, and administering local anesthetic blocks to all other sensory contributi ons in the exposed digit. Ten patients with 13 single digital nerve re pairs of equally severe injuries were studied at a mean of 41 months p ostoperatively. Standardized tests yielded an excellent result in 77% for static two-point discrimination (S2pd), 85% for moving two-point d iscrimination (M2pd), and 46.2% for Semmes-Weinstein monofilaments (SW MF). The same studies combined with nerve isolation yielded an excelle nt result in only 43% for S2pd, 43% for M2pd, and 0% for SWMF, These r esults indicate a statistically significant difference and the importa nce of crossover innervation from intact nerves in the long-term resul t of digital nerve repair. Nerve isolation study techniques are an imp ortant adjunct in assessing the outcome of nerve repair and are the on ly method of evaluating the true end result of nerve regeneration foll owing neurorrhaphy.