Effect of low power laser treatment on a traumatized disc in a rat model.

This study investigated the effects of low power laser on the healing process of a traumatized disc in an animal model. The experimental design consisted of 14 rats divided into the following three groups: Animals in group I (n = 5) served as controls with no surgery. Animals in group II (n = 5), the sham group, received a surgically created defect in the disc at L4/L5 level and received no other treatment. Animals in the third group (n = 4) received a similar defect to L4/L5 in similar fashion as described for animals in the sham group (group II) with the exception that they received laser of 830 nm wavelength treatment or irradiation for a period of 4 weeks. The animals were euthanized at 30 days post-implantation using overdose of isoflurane. The discs were then harvested in addition to the vital organs, the reproductive organs, and sample of the adjacent skeletal muscles. The hard and soft tissues were evaluated histopathologically by following laboratory standard techniques. The results of this study indicated that the discs of the laser treated animals healed in a greater magnitude than the sham group. Image analysis revealed that there was more disc formation in the laser irradiated animals than the sham. In conclusion, data obtained from this study demonstrated that laser irradiation delivered on traumatized discs resulted in a remarkable increase in discs regeneration and healing following trauma.