Lower Extremity Reconstruction with Anterolateral Thigh Free-Flap Anastomoses: A Computational Fluid Dynamic Analysis
Research article published in Journal of reconstructive microsurgery (2023)
Abstract
BACKGROUND: The anterolateral thigh free flap is an option for repairing soft tissue defects of the distal lower extremity. This flap uses the descending branch of the lateral circumflex femoral (LCF) artery as the flap vessel. The recipient vessel in these flaps is often the anterior tibial (AT), posterior tibial (PT), or peroneal (P) arteries. Computational fluid dynamic (CFD) evaluation of anastomoses between these vessels can optimize outcomes. METHODS: Thirty-eight CFD models were created to model end-to-side (ETS) and end-to-end (ETE) anastomoses for lower extremity reconstruction. Seven out of thirty-eight models represented ETS anastomoses between the LCF and AT arteries with varying anastomotic angles. Nine out of thirty-eight models represented 45-degree ETS anastomoses between varying diameters of the LCF and AT, PT, and P arteries. Nine out of thirty-eight models represented stenosis on the flap vessel and recipient vessel, pre- and post-bifurcation. Nine out of thirty-eight models represented ETE anastomoses, rather than ETS, with varying vessel diameters. Four out of thirty-eight models represented ETE anastomoses with varying regions and levels of stenosis. RESULTS: Stasis of blood flow in ETS models increased as anastomotic angle increased in a logarithmic relationship (R 2 = 0.918). Flow was optimized overall as flap and recipient vessel diameters approached one another. In ETS models, flap vessel and postbifurcation recipient vessel stenosis were found to substantially increase stasis. CONCLUSION: Selection of flap and recipient vessels with similar diameters can optimize outcomes in microvascular anastomoses. In the context of lower extremity reconstruction with the ALT flap, the PT artery can be recommended as a first-line recipient vessel due to its similar vessel caliber to the LCF and relative ease of surgical access compared with the P artery. Avoidance of areas of stenosis is recommended to ensure laminar flow and reduce the operative difficulty associated with performing anastomoses on nonpliable arteries. Striving for increased acuity of anastomotic angles is recommended to optimize the flow in ETS microvascular anastomoses.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
The anterolateral thigh free flap is an option for repairing soft tissue defects of the distal lower extremity.
Why This Matters for Hirudotherapy
This study used computational fluid dynamics to model 38 anastomotic configurations for lower extremity reconstruction with anterolateral thigh free flaps, evaluating how vessel diameter matching, anastomotic angle, and stenosis affect blood-flow stasis. The analysis recommended the posterior tibial artery as a first-line recipient vessel due to its similar caliber to the lateral circumflex femoral artery, and emphasized minimizing anastomotic angles and avoiding stenosis to maintain laminar flow. For ASH's domain, the relevance is indirect—medicinal leeches are sometimes deployed in free-flap surgery to manage venous congestion, but this study addresses intraoperative anastomotic optimization with no mention of leeches, hirudotherapy, or anticoagulation. The caveat is that this is a purely computational modeling study with no clinical leech content.
Citation
Lower Extremity Reconstruction with Anterolateral Thigh Free-Flap Anastomoses: A Computational Fluid Dynamic Analysis
Jinka SKA et al. · Journal of reconstructive microsurgery, 2023
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