Reversed arterial flow in free flap surgery for leg reconstruction

Lower Leg Reconstruction With Free Tissue Transfer Using Reverse Flow Recipient Vein: A Case Report

Since the introduction of distally based flap, the concept of reverse flow flap was expanded to free tissue transfers. For recipient vessels, retrograde arterial inflow is considered a safe option for anastomosis. However, the reliability of a retrograde recipient vein remains controversial. This report presents a case of successful lower leg reconstruction with free flap using a retrograde recipient vein. A 43-year-old woman had a mass lesion in the lateral side of the right calf, which was diagnosed as a malignant granular cell tumor. During wide excision of the tumor, the anterior tibial artery (ATA) and veins were ligated and resected at the bifurcation point from the popliteal artery and veins because the tumor abutted on the ATA near the bifurcation. The skin defect measured 17 × 7 cm with the proximal part of the tibia and lateral condyle exposed. A 19 × 7.5 cm anterolateral thigh flap was elevated, and anastomoses were performed using the distal end of the ATA and anterior tibial vein as retrograde recipient vessels. The flap was well perfused, and no signs of venous insufficiency were observed. Complete survival with no postoperative complications was achieved. In free tissue transfers of the lower leg, retrograde venous flow can be considered as a recipient vein when an antegrade vein is not available or has risks of venous insufficiency.

Multiple spurting test in microsurgical reconstruction of the lower extremities

Appropriate recipient artery is essential for the success of free flap reconstruction, however the selection could be difficult in a traumatized lower extremity. To detect unnoticed damage of the recipient artery, vascular integrity should be verified. For that purpose, we propose a simple and effective evaluation method, called Multiple Spurting Test (MST) this test esteems the dynamic status of the recipient arteries by measuring the length of arterial spurting. All the microsurgeons usually do something like MST: but it is not a standardized test yet.This study analyzed if this test could be a practical method in searching a safe recipient artery during microsurgical reconstruction of lower extremity. MST was employed in 163 flaps, all for lower extremity reconstruction. Fifteen flaps were re-explored in this series. Six of them had arterial problems, three in Anterior Tibial Artery (ATA), two in Posterior Tibial Artery (PTA) and one in Sural Artery (SA). The overall series' re-exploration rate, due to different complications, was 7% when ATA has been the recipient vessel, 7.6% with PTA and 30.7% with SA. Both ATA and PTA found equally reliable after examination with MST. We do believe that MST can effectively decrease the incidence of arterial complications and flap failure. Using this method, it is easier to choose a safe recipient artery for revascularization.

Reversed-flow superior thyroid artery: an alternative recipient vessel in head and neck reconstruction

In neoadjuvant intra-arterial infusion chemotherapy patients, the common recipient arteries are frequently damaged owing to preoperative chemotherapy-induced intima injury. When antegrade arterial inflow to the free flap is not available, end-to-side carotid arterial anastomosis or exploration of another recipient artery may be an appropriate solution. However, reversed arterial flow is an alternative to such a situation. We report a case with squamous cell carcinoma on the right buccal area, which was successfully reconstructed using a free anterolateral thigh flap with reverse superior thyroid arterial inflow. This alternative method might shorten the operation time and also reduce further exploration injury in the operation field.

Strategic considerations on the configuration of free flaps and their vascular pedicles combined with Ilizarov distraction in the lower extremity

For the injury of the lower leg associated with both bone and soft-tissue defect, the combined free flap and the Ilizarov distraction method were described as a useful treatment modality. During the procedure of distraction, however, revisions were frequently needed to change the pin position or to change the flap configuration. In case of flap ischemia, distraction should be delayed or abandoned. Then, a vascularized bone transfer might be necessary. To avoid these complications and achieve safe distraction, the configuration of the flap with its vascular pedicle should be carefully planned in terms of the future bony lengthening procedures and the concomitant soft-tissue changes of the lower leg. According to the response of local tissue to the distraction process, the lower limb can be divided into four compartments (active mobile, passive mobile, receptive, and restrictive). The configuration of the transferred free flap with its vascular pedicle can be classified into five types. To minimize the undue forces to the vascular pedicle and reduce the possibility of vascular compromise, the transferred free flap should have the configuration that its vascular pedicle lies in the territory of the mobile compartment. In performing free-tissue transfer combined with the Ilizarov method in the lower extremity, the configuration of the flap with its vascular pedicle should be carefully planned, and the characteristics of lower leg tissue should be kept in mind during the distraction.

Algorithm for recipient vessel selection in free tissue transfer to the lower extremity

The proper selection of a recipient vessel is essential for the success of free tissue transfer, especially when the transfer is to the lower extremity. However, a general agreement on which vessel to use has not been reached yet. Conflicting data have been reported on the survival and outcome of the transferred flaps, depending on the vessel used or the location of anastomosis. The aim of this study was to identify the patterns and problems in the selection of recipient vessels for free tissue transfer to the lower extremity and to establish a general guideline for proper selection. From September of 1990 to December of 1997, 50 consecutive, microvascular, free tissue transfers were performed on the lower extremity. The causes requiring soft-tissue coverage included trauma (25), unstable scar (11), chronic osteomyelitis (7), and tumors (7). The mean follow-up period was 22.4 months (range, 2 to 41 months). In 25 cases, the posterior tibial vessel was used as the recipient vessel. The microvascular anastomosis was done proximal to the zone of injury in 45 cases. The two most important factors in the selection of a recipient vessel are the site of injury and the vascular status of the lower extremity. Less important factors include the flap to be used, method, and site of microvascular anastomosis. All the currently feasible options for recipient vessels are included, and the opinions of other surgeons are reviewed. A general guideline is established, and an algorithm for the proper selection of a recipient vessel is proposed. This algorithm is a fast and convenient guide for evaluating the wound and planning the free flap to the lower extremity.