Experimental peripheral nerve repair: environmental control directed at the cellular level

This study recognizes recent advances in the understanding of the anatomy and physiology of peripheral nerves at the cellular level. It has reproduced study conditions originally advocated by de Medinaceli and coworkers, with modifications. Eighty-four rats were divided into three groups. Group A underwent sciatic nerve transection and standard perineurial repair. Group B nerves were frozen, severed with a vibrating blade, and reconnected by tubulization with a rubber cuff while bathed in solutions designed to inhibit Ca++-calmodulin activation, maintain colloid osmotic pressure, and mimic ambient electrolytic conditions. Group C underwent a similar procedure as group B, with the rubber cuff replaced by a polyglycolic acid mesh. All animals were randomized and evaluated functionally in terms of a sciatic index. By post-operative day 225, animals of group A recovered 37% of function, group B recovered 74%, and group C recovered 67%. Compound action potential recordings revealed a velocity recovery of 41% in group A, 70% in group B, and 81% in group C. Microscopic evaluation provided evidence for corresponding structural improvement. This new method of nerve repair is uncomplicated, relatively inexpensive, and easily adaptable to other animal models.