Preserving the Blood Flow of the Recipient Artery in Cross-Leg Free Flap Procedure for Lower Extremity Reconstruction.

When there is no suitable vessel in the injured leg for microsurgical transfer, cross-leg free flaps can be considered for lower extremity reconstruction. This report describes patients who experienced lower extremity trauma and underwent reconstruction with cross-leg free flaps with preserved blood flow in the recipient artery. Anterolateral thigh flap is preferred for small to moderate defects. The descending branch of the lateral femoral circumflex artery was dissected 2 cm proximally and distally and was prepared in a T-shape. The branches of the T were anastomosed to the recipient artery in the contralateral leg in the first session of the cross-leg free flap procedure. After 3 weeks, the flap artery was separated from the bifurcation. For large defects, the latissimus dorsi flap was chosen. The thoracodorsal artery was anastomosed to the contralateral posterior tibial artery in the first session. After 3 weeks, to provide recipient vessel integrity, the thoracodorsal artery was transected from the flap and anastomosed to the distal stump of the posterior tibial artery. Between January 2017 and January 2019, 8 defects were reconstructed using an anterolateral thigh flap; the remaining 4 defects were reconstructed using a latissimus dorsi flap. All flaps survived without complications. Anterograde flow distal to the anastomosis was confirmed in all recipient arteries via Doppler ultrasound. In cross-leg free flaps, the continuity of the recipient artery can be established to prevent diminished blood flow to the recipient extremity.