[sensorimotor differentiated reconstruction of peripheral nerves--a methods of intraoperative identification of motor...

In 1975, Freilinger et al. identified motor fibres by acetylcholinesterase (AChE) histochemistry. Precise identification of motor fascicles in cases of mixed peripheral nerve dissection became possible, and selective fascicular nerve repair could be performed. Using this technique, two separate operations were necessary for definitive nerve repair, since histochemical analysis took 28 hours. A modified AChE staining technique now offers results within one hour. In seven cases of human median and three cases of human ulnar nerve lesions, nerve biopsies were obtained and underwent both modified and standard histochemical staining. The standard procedure did not render any further information about the AChE activity indicating that both methods are equally reliable. Photomicrographs of the nerve specimen with motor fascicles marked on them were completed in all cases of the modified AChE staining method one hour after obtaining the biopsies. Intraoperative identification of motor fascicles by rapid AChE staining technique was performed in two cases of acute injuries of the median nerve, radial artery and musculotendineous system of the forearm. Biopsies were obtained at the beginning of the operation. Histochemical analysis was done while tendons and arteries were reconstructed and selective fascicular nerve repair was possible at the end of the operation. The rapid AChE staining may be applied intraoperatively to acute nerve injury and late peripheral nerve reconstruction provided the nerve is expected to already contain segregated motor fascicles.