The functional recovery of peripheral nerves following defined acute crush injuries

Abstract

This study evaluates the effect of crushing load on functional recovery of the sciatic nerve. Male Sprague-Dawley rats were divided into five groups: sham operation, resected sciatic nerve, and 100 g (13 mm Hg/mm2), 500 g (50 mm Hg/mm2), and 15,000 g (1,000 mm Hg/mm2) of sciatic crush load (groups 1-5). In groups 3-5, a 5-mm segment of sciatic nerve was crushed for 10 min using a specially designed crushing device. Motor functional recovery was assessed from hind-limb walking tracks by calculating a sciatic functional index. There was no detectable functional deficit in the group receiving sham operations, while the resected sciatic nerve group exhibited complete dysfunction for the full duration of the experiment. All groups subjected to crush exhibited an initial deficit that gradually recovered to normal by day 14 (100-g crush), day 39 (500-g crush), and day 53 (15,000-g crush). Histological changes were also related to the initial crushing load and the length of the recovery period. Results indicate that the crushing device described is able to administer an adjustable, defined crush injury to the rat sciatic nerve, and that the functional deficit resulting from such an injury can be easily monitored with a sciatic functional index. The rate of recovery of crushed nerves was directly related to the initial load. All crushed nerves recovered in this experiment, even after the application of a 15,000-g load for 10 min.

The sciatic nerve injury model in pre-clinical research

“…Various methods have been devised for producing the crush injury, including various surgical instruments (Chen et al, 1992;Kingery et al, 1994, Savastano et al, 2014 and compression devices (Navarro and Kennedy, 1989;Radevik and Lundborg, 1997;Oliveira et al, 2001;Srikcioglu et al, 2007). The compression is applied with the goal of interrupting the continuity of all axons (axonotmesis) without interruption of the connective scaffold of the nerve (especially the epineurium) and thus without losing continuity of the nerve trunk.…”

Erythropoietin Promotes Functional Recovery and Enhances Nerve Regeneration after Peripheral Nerve Injury in Rats

“…25 Briefly, the animals were allowed to walk down a corridor, leaving blue footprints on the floor paper impregnated with a 0.5% solution of the anhydrous form of bromophenol blue in absolute acetone. The distance between the first and fifth toes (TS), the distance between the second and fourth toes (IT), and the print length (PL) were measured.…”

Effects of Selenium on Axon and Myelin Healing in an Experimental Sciatic Nerve Injury Model

“…In empirical studies, the models using sciatic nerve mechanical compression have been used commonly (3). In these studies, mechanical compression of the sciatic nerve has been created by different compression devices (4,(20)(21)(22). One of these compression devices is aneurysm clips, and they have been used in different studSelenium on axon and myelin damage ies.…”