Correlation between Functional Index and Morphometry to Evaluate Recovery of the Rat Sciatic Nerve Following Crush Injury: Experimental Study

Elias F. Oliveira; Nilton Mazzer; Cláudio H. Barbieri; Marcelo Selli

doi:10.1055/s-2001-12691

Journal of Reconstructive Microsurgery, Table of Contents

J Reconstr Microsurg 2001; 17(1): 069-076
DOI: 10.1055/s-2001-12691
DOI: 10.1055/s-2001-12691

Correlation between Functional Index and Morphometry to Evaluate Recovery of the Rat Sciatic Nerve Following Crush Injury: Experimental Study

Elias F. Oliveira, Nilton Mazzer, Cláudio H. Barbieri, Marcelo Selli

Hand Surgery and Microsurgery Division and Bioengineering Laboratory, Department of Orthopaedic and Trauma Surgery, Ribeirão Preto School of Medicine, São Paulo University, Brazil

Abstract

ABSTRACT

An experimental study on the correlation between functional and morphologic recovery of crushed sciatic nerves was carried out in rats. The sciatic nerve of 33 rats, divided into three groups, was submitted to controlled crushing injury on a 5-mm long segment, in a universal testing machine for 10 min with three different loads (100, 500, and 15000 g, respectively). Functional recovery was evaluated, using a modified sciatic functional index (SFI) at weekly intervals up to the 60^th postoperative day, at which time, the animals were sacrificed for histologic and morphometric studies of the nerves. Results were compared with those of normal untouched nerves and nerves submitted to segmentary resection without repair. Initial loss of function was observed in all animals with crush injury, but recovery to a nearly normal SFI occurred after progressively longer intervals (25, 39, and 53 days), as a function of load. Nerve-fiber density was increased in the groups submitted to lower loads, but statistically significantly decreased in the animals submitted to the 15000-g crush. The authors conclude that the SFI is directly correlated with nerve-fiber density and, therefore, is an adequate tool for evaluating sciatic functional deficiency in the rat.

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References

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