Musculoskeletal stretch injury shows a faster recovery compared to contusion in rats

Background: The musculoskeletal repair, in most cases, follows the typical inflammatory process. Although the majority of treatments result in good prognosis, the knowledge concerning basic biochemical principles, regeneration and repair mechanisms of skeletal muscles may help in recovery and accelerate the return to sport, helping to carefully choose the more appropriate therapeutic techniques for the injury management.

Objective: This study investigated the effects of contusion and stretch injury on the oxidative damage in the gastrocnemius muscle of rats.

Methods: The biochemical analysis was performed on the 1, 3, 5, or 7 days after the injuries and behavior analysis was performed until 48 hours after injuries to evaluate the healing process changing characteristics.

Design: Experimental animal study.

Results: The contusion and stretch injury increased the oxidative stress markers levels; however, the injuries showed significant differences from each other in the markers of oxidized dichlorofluorescein, superoxide dismutase enzyme activity and N-acetyl-beta-glucosaminidase enzyme activity in skeletal muscle tissue. Furthermore, the injuries showed differences in behavioral analyses in the beam walking test.

Conclusion: In conclusion, we could infer that the stretch injury presents an early increase in the activity of the N-acetyl-β-D-glucosaminidase enzyme, indicating a possible macrophage increase in the first hours after injury.