The Effects of Photobiomodulation Therapy on the Healing of Eastern Box Turtle (Terrapene carolina) Shells

Abstract

Photobiomodulation therapy (cold laser or low-level laser therapy) has been evaluated in human and small animal medicine; however, there is a lack of knowledge about the role photobiomodulation therapy could play in reptile rehabilitation and release. This study used a quantifiable unit, Hounsfield units (bone density measurement), in computed tomography (CT) to evaluate if photobiomodulation therapy showed a significant healing difference between groups treated with photobiomodulation and those that were not. This study included 20 eastern box turtles (Terrapene carolina) presented to a rehabilitation center that sustained shell fractures without penetrating the coelom. They all received similar medical treatments, except that the photobiomodulation group received 250 Hz of red light laser for three minutes three times a week for eight weeks. The turtles were evaluated over the course of two months of therapy. Computed tomography scans were performed prior to therapy, at the midpoint of treatment (one month postinjury), and at the end of the study (two months postinjury). The average Hounsfield units of the fractures were evaluated using nonparametric means, the Wilcoxon/Kruskal–Wallis tests (ranked sums), and found that there were no significant differences in shell density between the photobiomodulation and control groups amongst the scans. This study did find that there was a significant difference (p = 0.0455) between the two groups in regard to the width of the fracture between pre- and post-treatment scans. This study found that the photobiomodulation group had a significantly decreased width of the fracture site between pre-treatment and post-treatment measurements, showing that photobiomodulation could be a relatively easy and effective treatment to promote healing of fractured turtle shells.