TY - JOUR

T1 - Haemodynamically stimulated and in vivo generated axially vascularized soft-tissue free flaps for closure of complex defects

T2 - Evaluation in a small animal model

AU - Schmidt, Volker J

AU - Wietbrock, Johanna O

AU - Leibig, Nico

AU - Hernekamp, Jochen F

AU - Henn, Dominic

AU - Radu, Christian A

AU - Kneser, Ulrich

N1 - Copyright © 2017 John Wiley & Sons, Ltd.

PY - 2018

Y1 - 2018

N2 - The arteriovenous (AV) loop model permits the creation of significant volumes of axially vascularized tissue that represents an alternative to conventional free flaps, circumventing their common limitations. However, such AV loop-based flaps have never before been examined in standardized animal models with respect to their suitability for reconstruction of critical bone-exposing defects. In the course of our preliminary studies, we implemented a novel defect model in rats that provides standardized and critical wound conditions and evaluated whether AV loop-generated flaps are suitable for free microsurgical transfer and closure of composite defects. We compared three groups of rodents with similar scapular defects: one received the AV flap, whereas controls were left to heal by secondary intention or with supplementary acellular matrix alone. To create the flaps, AV loops were placed into subcutaneous Teflon chambers filled with acellular matrix and transferred to the thigh region. Flap maturation was evaluated by histological analysis of angiogenesis and cell migration at days 14 and 28 after loop creation. Flap transfer to the scapular region and microsurgical anastomoses were performed after 14 days. Postoperative defect closure and perfusion were continually compared between groups. Within the AV flap chamber, the mean vessel number, cell count and the proportion of proliferating cells increased significantly over time. The novel defect model revealed that stable wound coverage with homogeneous vascular integration was achieved by AV loop-vascularized soft-tissue free flaps compared with controls. In summary, our study indicates for the first time that complex composite defects in rats can successfully be treated with AV loop-based free flaps.

AB - The arteriovenous (AV) loop model permits the creation of significant volumes of axially vascularized tissue that represents an alternative to conventional free flaps, circumventing their common limitations. However, such AV loop-based flaps have never before been examined in standardized animal models with respect to their suitability for reconstruction of critical bone-exposing defects. In the course of our preliminary studies, we implemented a novel defect model in rats that provides standardized and critical wound conditions and evaluated whether AV loop-generated flaps are suitable for free microsurgical transfer and closure of composite defects. We compared three groups of rodents with similar scapular defects: one received the AV flap, whereas controls were left to heal by secondary intention or with supplementary acellular matrix alone. To create the flaps, AV loops were placed into subcutaneous Teflon chambers filled with acellular matrix and transferred to the thigh region. Flap maturation was evaluated by histological analysis of angiogenesis and cell migration at days 14 and 28 after loop creation. Flap transfer to the scapular region and microsurgical anastomoses were performed after 14 days. Postoperative defect closure and perfusion were continually compared between groups. Within the AV flap chamber, the mean vessel number, cell count and the proportion of proliferating cells increased significantly over time. The novel defect model revealed that stable wound coverage with homogeneous vascular integration was achieved by AV loop-vascularized soft-tissue free flaps compared with controls. In summary, our study indicates for the first time that complex composite defects in rats can successfully be treated with AV loop-based free flaps.

KW - Animals

KW - Blood Vessels/physiology

KW - Cell Movement

KW - Cell Proliferation

KW - Female

KW - Free Tissue Flaps/physiology

KW - Hemodynamics/physiology

KW - Models, Animal

KW - Neovascularization, Physiologic

KW - Rats, Sprague-Dawley

KW - Scapula/pathology

U2 - 10.1002/term.2477

DO - 10.1002/term.2477

M3 - Journal article

C2 - 28509443

VL - 12

SP - 622

EP - 632

JO - Journal of Tissue Engineering and Regenerative Medicine

JF - Journal of Tissue Engineering and Regenerative Medicine

SN - 1932-6254

IS - 3

ER -