Medial Sural Artery Perforator Flap for Leg and Knee Coverage: Extended Skin Paddle With 2 Perforators

The clinical application of V-Y advanced flap pedicled with freestyle perforator flap for repairing small range defects in the anterior knee region

Introduction

This study aims to investigate the clinical efficacy of V-Y advanced flap pedicled with freestyle perforator flap for repairing small range defects in the anterior knee region.

Methods

8 patients with skin and soft tissue defect/necrosis in the anterior knee area admitted to the Changshu No.1 People's Hospital from January 2021 to January 2022 were selected, with a defect range of 4 cm × 3 cm-9 cm × 6 cm, designed a V-Y advanced flap pedicled with freestyle perforator flap to repair the wound in the anterior knee area. Adjust the size and position of the flap according to the number and position of perforating branches found during the surgery, with a cutting area of 6 cm × 5 cm-14 cm × 10 cm and the supply area was directly pulled and sutured.

Results

4 patients were repaired by flaps pedicled with 2 perforating branches, 2 patients were repaired by flaps pedicled with 1 perforating branch and 2 patients were repaired by flaps pedicled with 3 perforating branches. 4 patients were repaired by flaps pedicled with 2 perforating branches, 2 patients were repaired by flaps pedicled with 1 perforating branch and 2 patients were repaired by flaps pedicled with 3 perforating branches. All flaps survived and following up for 6-15 months, the blood supply, appearance, and color of the flap were satisfactory, and the functions of knee joint flexion and extension were well preserved.

Discussion

The V-Y advancement flap pedicled with freestyle perforator flap has the advantages of reliable blood supply, simple surgical operation, texture and thickness similar to the skin of the anterior knee area, and direct suture of the donor area. It is a perforator flap with good repair effect for small scale defects in the anterior knee area.

A Cadaveric Study on Perforator Anatomy of the Medial Sural Artery Perforator Flap

Background  The medial sural artery perforator (MSAP) flap was described by Cavadas et al in 2001. The aim of this study was to analyze the flap characteristics in the regional population and was planned as a cadaveric dissection study. Methods  Thirty-three legs of fresh cadavers were studied for perforator characteristics, length, and origin of pedicle and skin paddle thickness. Observations were documented and analyzed. Results  Seventeen right legs (51.5%) and sixteen left legs (48.5%) were studied. Twenty-five pedicles originated from popliteal artery (86.2%) and four (13.8%) from the common sural trunk. No perforators were seen in four legs. The mean number of perforators is 2 (0-6). The mean distance of perforator from midpoint of popliteal fossa was 10.7 cm (8-13 cm) and from posterior midline it was 3.2 cm. The mean size of the perforator was 1.1 ± 0.8 mm (0.8-1.5 mm). The mean pedicle length was 9.3 ± 1.3 cm. The mean flap thickness was 4.3 ± 0.7 mm (3.0-5.5 mm). There was no correlation for flap or perforator characteristics with side of leg. Conclusion  This study concludes that MSAP is a good flap in terms of perforator characteristics, pedicle length, and flap thickness, when a medium sized thin flap with long pedicle is needed. The location of perforator on calf varies in different population. Being a perforator flap, anatomical variability is common and should be thought of while choosing this flap.

The Medial Sural Artery Perforator Flap: A Historical Trek from Ignominious to “Workhorse”

Rather than just another “review,” this is intended to be an “overview” of the entire subject of the medial sural artery perforator (MSAP) flap as has been presented in the reconstructive literature from its inception in 2001 until the present, with any exceptions not purposefully overlooked. Unfortunately, the pertinent anatomy of the MSAP flap is always anomalous like most other perforator flaps, and perhaps even more variable. No schematic exists to facilitate the identification of a dominant musculocutaneous perforator about which to design the flap, so some adjunctive technology may be highly valuable for this task. However, if a relatively thin free flap is desirable for a small or moderate sized defect that requires a long pedicle with larger caliber vessels, the MSAP flap deserves consideration. Indeed, for many, this has replaced the radial forearm flap such as for partial tongue reconstruction. Most consider the donor site deformity, even if only a conspicuous scar on the calf, to be a contraindication. Yet certainly if used as a local flap for the knee, popliteal fossa, or proximal leg, or as a free flap for the ipsilateral lower extremity where a significant recipient site deformity already exists, can anyone really object that this is not a legitimate indication? As with any perforator flap, advantages and disadvantages exist, which must be carefully perused before a decision to use the MSAP flap is made. Perhaps not a “workhorse” flap for general use throughout the body, the MSAP flap in general may often be a valuable alternative.

Propeller Flaps in Lower Extremity Reconstruction

Propeller flaps represent an outstanding alternative to conventional pedicled and free flap options in lower extremity reconstruction, offering significant advantages over the latter. An understanding of the perforasome concept, hot and cold perforator locations, and basic flap design enable the surgeon to readily harvest flaps based on any clinically relevant perforator in freestyle fashion. The purpose of this article is to review fundamentals of propeller flap design and harvest in the lower extremity and discuss reconstructive strategies by level of injury.

Lower limb perforator flaps: Current concept

Following a long period dominated by random fasciocutaneous flaps or muscle flaps, solutions to cover the lower limb have been largely diversified by the advent of so-called "perforator" flaps. Extended knowledge of vascular anatomy has propagated the development of this innovative procedure, in the objective of reducing morbidity. The existence of close to 400 perforator vessels in the body makes it possible to offer new flap perspectives for many defects, which were sometimes previously impossible to manage before except by free flap. For us, perforator flaps have become the current first-line solutions for small to medium size loss of substances. Understanding of vascular physiology and surgical experience are essential in choosing indications, detecting perforators, and modeling flaps to be optimally positioned in the reconstructive decisional algorithm. New skills are needed to master this type of reconstruction and limit failures, which implies a learning curve not only for flap design, perforator detection and surgical procedure, but also for monitoring and management of complications. In this manuscript, we outline the concepts and principles of the majority of the pedicled perforator flaps available for coverage of the lower limb, based on experience of more than 400 perforator flaps suitable for this localization.

Soft tissue coverage options around the knee

Defects around the knee exhibit various etiologies and pose challenges to both orthopedists and plastic surgeons. While a number of reconstructive coverage options are available, flaps are almost always required for complex defects. Many local flaps are easily placed, including muscle and perforator flaps sourced from the thigh to the leg. As the recipient vessels lie deep, free tissue transfers are challenging. Good postoperative management and efficient collaboration between orthopedic and reconstructive surgeons are the keys to successful knee reconstruction, restoring an esthetic contour and preserving joint function.