Abstract:

Abstract:Objective To observe the vascular casting specimen of medial supramalleolar cutaneous branch of posterior tibial artery，and investigate  the  surgical design of medial supramalleolar cutaneous branch flap of posterior tibial artery for the repairing of leg-foot skin and soft tissue defect，and illuminate the blood supply and characteristics of medial supramalleolar cutaneous branch of posterior tibial artery  to provide anatomical basis for clinical application.Methods Vascular casting and gradation etching were performed on 20 fresh adult cadaver lower legs，series data were obtained with vernier caliper and graph paper;the emerging point，branches，distribution，anastomosis，shape and area of blood supply of medial supramalleolar perforating branch of posterior tibial artery were collected and analyzed．Results In 90%，the emerging point of medial supramalleolar cutaneous branch of posterior tibial artery were concentrated in 8-12 cm of projection distance on condyle-ankle line，the mean diameter of the vessel was （0.96±0.24）mm；anatomical blood supply region was similar to oval，the area was （72±8）cm²，occuping 14.22% of the whole shank.The emerging point of medial supramalleolar cutaneous branch of posterior tibial artery was made as zero point，the line between emerging point and the middle point of posterior border internal malleolus and calcaneal tendon as longitudinal axis，the line through zero and vertical to longitudinal axis as horizontal axis，the blood supply region of medial supramalleolar perforating branch of posterior tibial artery was divided into four quadrants，the blood supply areas of every quadrant were upper inner quadrant（15±2）cm²,upper outer quadrant（8±3 ）cm²，lower inner quadrant（25±4）cm²，lower outer quadrant （24±3） cm²；the second class branch and third class branch were distributed more in upper inner and lower outer quadrants，the axial direction (Dmax/L) was 1.47±0.31；the cutaneous branch had abundant vascular anastomosis with vessels nearby，and participated in the composition of nutrient vessel chains of saphenus nerve，the effective blood supply region could reach 2/3 of  inferior medial facies of the shank． Conclusion Medial supramalleolar cutaneous branch of posterior tibial artery has relatively invariable emerging point，large blood supply region,and is easy to cut and transpose.According to its branches，distribution and anastomosis conditions，the surgical design of double axis-point and double axis flaps with medial supramalleolar cutaneous branch of posterior tibial artery can be made as feeding artery to repair leg-foot skin and soft tissue defect．

Key words: posterior tibial artery, medial supramalleolar perforator, axis points flap, dual axis flap, skin and soft tissue defects