Effect of nerve graft porosity on the refractory period of regenerating nerve fibers.
OBJECTIVE
In the present study the authors consider the influence of the porosity of synthetic nerve grafts on peripheral nerve regeneration.


METHODS
Microporous (1-13 microm) and nonporous nerve grafts made of a copolymer of trimethylene carbonate and epsilon-caprolactone were tested in an animal model. Twelve weeks after surgery, nerve and muscle morphological and electrophysiological results of regenerated nerves that had grown through the synthetic nerve grafts were compared with autografted and untreated (control) sciatic nerves. Based on the observed changes in the number and diameter of the nerve fibers, the predicted values of the electrophysiological parameters were calculated.


RESULTS
The values of the morphometric parameters of the peroneal nerves and the gastrocnemius and anterior tibial muscles were similar if not equal in the rats receiving synthetic nerve grafts. The refractory periods, however, were shorter in porous compared with nonporous grafted nerves, and thus were closer to control values.


CONCLUSIONS
A shorter refractory period enables the axon to follow the firing frequency of the neuron more effectively and allows a more adequate target organ stimulation. Therefore, porous are preferred over nonporous nerve grafts.
Vleggeert-Lankamp
Carmen L A M
CL
Department of Neurosurgery, Leiden University Medical Centre, Leiden, The Netherlands. cvleggeert@lumc.nl
Wolfs
Jasper
J
Pêgo
Ana Paula
AP
van den Berg
Rutgeris
R
Feirabend
Hans
H
Lakke
Egbert
E
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D005260:Female; D008855:Microscopy, Electron, Scanning; D008959:Models, Neurological; D018482:Muscle, Skeletal / Q000294:innervation; D009412:Nerve Fibers / Q000502:physiology; D009416:Nerve Regeneration / Q000502:physiology*; D010523:Peripheral Nervous System Diseases / Q000503:physiopathology / Q000601:surgery; D019736:Prostheses and Implants / Q000648:ultrastructure; D019919:Prosthesis Implantation; D051381:Rats; D017208:Rats, Wistar; D012584:Sciatic Nerve / Q000502:physiology* / Q000601:surgery*