A comparative study of the established methods and evaluation of rat trauma models

Background: Scientific animal models are indispensable for studying trauma repair. This work aimed at establishing a more scientific rat trauma model by studying different rat trauma models caused by different trauma numbers, locations, and trauma attachment tension unloaders and rat age. Methods: A four-trauma self-upper, lower, left and right control model; a two-trauma self-trauma bare and ring control model; and a young and old rat trauma model were created to evaluate the condition of these traumas. Results: In the four-trauma self-control model, the healing status of the upper proximal cephalic trauma was better than that of the lower proximal caudal trauma, whereas there was no significant difference between the left and right trauma. The healing rate and postwound condition of the trauma with a ring control in the two-trauma model were better than those of the bare side. The healing speed of the old rats was slower, and the amount of extracellular matrix in the subcutaneous tissue after healing was significantly lower than that of the young rats. Conclusion: The double trauma with a ring is a more scientific and reasonable experimental model. There is a significant difference between young and old rats in the wound healing process. Therefore, the appropriate age of the rats should be selected according to the main age range of the patients with similar conditions in the clinical setting being mimicked.