The Imageology Study and Clinical Application of Perforating Branch of Posterior Tibial Artery.

Background: It is necessary to precisely locate the branches for better result of flap transplantation for the high variability of perforating branches of posterior tibial artery (PTA). In the research, digital subtraction angiography (DSA) and high-frequency ultrasound are jointly used to study the distribution and exact location of PTA perforating branches to guide clinical practice.

Methods: From January 2020 to December 2022, 16 patients underwent DSA examination and 5 of them accepted further high-frequency ultrasound examination. The authors analyzed the distribution, number, location, direction, and lengths of PTA branches and used PTA perforator flaps to repair middle and inferior lower leg defects according to the above imaging findings. The donor site was repaired with skin grafts or a sequential PTA perforator flap.

Results: A total of 81 branches of PTA were identified in 16 patients. Most of the perforating branches were in the middle and distal thirds of tibia. There was a significant correlation between the length of perforating branches and their perforating sites. Cluster analysis showed that larger branches appeared most frequently in the range of 15 to 20 cm from the tip of the inner ankle. 5 cases of PTA perforator flaps survived well.

Conclusion: DSA can clearly show the distribution of PTA and its branches, especially the dominant ones. The imaging findings can effectively guide PTA perforator flap design and harvesting, and thus improve the result of flap transplantation.