Lack of effectiveness of laser therapy applied to the nerve course and the correspondent medullary roots.
OBJECTIVE
To investigate the influence of low intensity laser irradiation on the regeneration of the fibular nerve of rats after crush injury.


METHODS
Twenty-five rats were used, divided into three groups: 1) intact nerve, no treatment; 2) crushed nerve, no treatment; 3) crush injury, laser irradiation applied on the medullary region corresponding to the roots of the sciatic nerve and subsequently on the course of the damaged nerve. Laser irradiation was carried out for 14 consecutive days.


RESULTS
Animals were evaluated by functional gait analysis with the peroneal functional index and by histomorphometric analysis using the total number of myelinated nerve fibers and their density, total number of Schwann cells, total number of blood vessels and the occupied area, minimum diameter of the fiber diameter and G-quotient.


CONCLUSIONS
According to the statistical analysis there was no significant difference among groups and the authors conclude that low intensity laser irradiation has little or no influence on nerve regeneration and functional recovery. Laboratory investigation .
Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo - Ribeirão Preto, SP, Brazil.
Fausto Fernandes de Almeida
FF
Sousa
Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo - Ribeirão Preto, SP, Brazil.
Thaís Lopes
TL
Ribeiro
Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo - Ribeirão Preto, SP, Brazil.
Valéria Paula Sassoli
VP
Fazan
Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo - Ribeirão Preto, SP, Brazil.
Claudio Henrique
CH
Barbieri
Crush injury; Fibular nerve; Laser therapy; Nerve regeneration; Rats