The Anatomy And Clinical Study On The Reversed Island Flap With The Popliteo-posterior Intermediate Cutaneous Artery

【Objective】To provide anatomic basis for reversed island flap with the Popliteo-posterior intermediate cutaneous artery (PPICA).【Methods】10 fresh cadaveric specimens were injected through the femoral artery using the red latex and restored in the icebox. Before dissection, the specimens were thrawed in the room temperature.These fresh speciments were dissected with 5 magnification using loupe. The PPICA and its branches were observed. the origin and insertion and diameter and length of the dominant vessels are measured. The relationship between the cutaneous branches of the PPICA and the third perforater of the deep femoral artery were observed. The reversed island flap with the ascending branch of the PPICA was designed, and was applied in 2 cases clinically.【Results】1. The PPICA were in 10 specimens (100%). This artery arises from the popliteal artery 28.50±4.92mm proximal to the original point (OP). the OP is the middle point of the Popliteal-line. The starting point diameter of the PPICA is 1.72±0.12mm. There is a semimembranous muscular branches which diameter is 0.56±0.05mm arising from the PPICA 22.06±3.77mm proximal to the starting point of PPICA in 3 specimens. The PPICA perforate from fascia 33.36±5.39mm proximal to starting point. and then it divides into ascending and descending branches. the diameter of the descending branch is 0.59±0.12mm, it descends with small saphenous vein and sural nerve. The diameter of the ascending branch is 0.95±0.16mm, it ascend along spatium intermusculare of semimembranosus and biceps femoris. there are 18~25 branches arise from the ascending branch, the average diameter of these branches is 0.46±0.15mm. these branches extend from center line to two side extensions, and they can reach 5.6cm. moreover, the branches anastomose with each other. the ascending branch anastomoses with the descending branch of third perforating artery of Deep femoral artery (DTPA) 110.84±9.18mm proximal to the OP. The diameter of the DTPA is 0.84±0.12mm. The third perforating artery of Deep femoral artery (TPA) divides into ascending and descending branches. The descending branch anastomoses with the ascending branch of the PPICA. The ascending branch of the TPA ascends along with the median line to the back of the thigh.the diameter of the ascending branch is 0.92±0.12mm. the terminal branch anastomoses with the terminal of the inferior gluteal artery, and become the supply artery of the posterior femoral cutaneous nerve.2. The supply scope of ascending branch of the PPICA is: the length from the proximal to the OP is about 250.03±9.24mm; the remote-line is Popliteal-line; on both sides, the length from the center line to either side is the 5.5cm. The Flap can be size: 25cm×11cm. 3. And ascending branch of the PPICA accompanied by two vein. The vein converge in popliteal fossa, the diameter was 1.41±0.11mm, the vein converging into the small saphenous vein. the small saphenous vein accompanied by the descending branch of the PPICA 161.58±9.67mm remote to the OP, and then converging into Popliteal vein in popliteal fossa.4. Two patients were treated using this flap clinically. The size of the flap in one case is 17cm×6cm, and the function of the knee is normal after operation. The size of the other case is 26cm×15cm, and most of the flap survived, about 7cm×3cm flap did not suivive. then we treat it with dermepenthesis, the skin is survived. The texture and color of the flap is good.【Conclusions】The location and course of the ascending branch of the PPICA are consistent, and the rotation point is 28 mm proximal to the OP. The supply scope of the flap with the PPICA as a pedicle can be 25cm×11cm. The flap can be a better choice to be used to repair soft tissue defect in the knee.