The effect of different modes of microneedling technique on random flap survival in rats.

Objective: The investigation and practice of physical therapy in flap surgery are still scare. The purpose of this study is to evaluate the impact of different microneedling interventions on survival of random pattern flaps in rats, attempting to determine the optimal microneedling protocols for improvement of flap survival.

Methods: Eighty male Sprague-Dawley rats were randomly divided into four groups, with 20 in each group (group A, B, C, and D). A 3 cm × 9 cm rectangular random flap as the McFarlane flap was adopted in each group. In groups A and B, microneedling treatment was performed before and after surgery, respectively. While animals in group C were received both pre- and postoperative microneedling treatment. Group D was used as a control group, which was only exposed to surgery. Flap survival, flap blood flow, number of capillary formations, the expressions of CD31, CD34, HIF-1α, and vascular endothelial growth factor (VEGF) were detected in each group and compared.

Results: On the 7th day postoperatively, significant improvements with microneedling treatment were found in flap survival rate (p = 0.007), blood flow (p = 0.024), the expression levels of CD34 (p = 0.005), and the VEGF (p < 0.01). Furthermore, the VEGF expression level was significantly higher in group B when compared with the other three groups (all p < 0.01). However, there was no significant difference in the number of new blood vessels and other immunohistochemical indicators among the four groups (all p > 0.05).

Conclusion: Microneedling treatment especially postoperative intervention can significantly improve the survival of random flaps in rats.