A-A Type, Arterialized, Venous, Flow-Through, Free Flap for Simultaneous Digital Revascularization and Soft Tissue Reconstruction???Revisited

Flow-Through Free Anterolateral Thigh Flap in Reconstruction of Severe Limb Injury

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This study aimed to present the use of flow-through free anterolateral thigh (ALT) flap for the reconstruction of severe limb injury.

Free medialis pedis venous flap transfer for reconstruction of volar finger defects: Clinical application and esthetic evaluation

BACKGROUND

There have been many reports about venous flaps, which are often used for the reconstruction of soft tissue defects after finger injury because such flaps are simple to elevate. Recently, high viability rates and nearly normal histological findings were reported for venous flaps, although the mechanism of flap survival remains unclear. This study investigated the esthetic outcomes after the reconstruction of volar finger defects with free medialis pedis venous flaps, which are venous flaps that elevated between the submalleolar and medial plantar regions.

MATERIALS AND METHODS

Reconstruction of volar finger defects was performed in 6 patients. All flaps were arterialized flow-through flaps with the venous anastomosis as the outflow. All 6 patients were men, with a mean age of 32.0 years. The defect involved the finger shaft in 4 patients and the finger pulp in 2 patients, and the mean size of the venous flap was 16.7 mm (width) × 34.2 mm (length). Five plastic surgeons specializing in maxillofacial surgery evaluated the color match of the flaps at 6 months postoperatively by assigning a score (maximum: 5 points).

RESULTS

The flap showed complete viability with little postoperative atrophy in all 6 patients. The mean color match score for the flaps was 3.7, and it decreased as the flaps were raised further from the medial plantar region.

CONCLUSION

Free medialis pedis venous flaps can be used for the reconstruction of volar soft tissue defects of the finger. Acceptable esthetic results can be obtained if flaps are harvested from an appropriate location in the medialis pedis region by a suitable method.

Systematic Review and Meta-Analysis of Unconventional Perfusion Flaps in Clinical Practice

BACKGROUND

Although unconventional perfusion flaps have been in clinical use since 1975, many surgeons are still deterred from using them, because of some reports of high necrosis rates.

METHODS

The authors performed a systematic review and meta-analysis of all articles written in English, French, German, Spanish, and Portuguese on the clinical use of unconventional perfusion flaps and indexed to PubMed from 1975 until July 15, 2015.

RESULTS

A total of 134 studies and 1445 patients were analyzed. The estimated survival rate of unconventional perfusion flaps was 89.5 percent (95 percent CI, 87.3 to 91.3 percent; p < 0.001). Ninety-two percent of unconventional perfusion flaps (95 percent CI, 89.9 to 93.7 percent; p < 0.001) presented complete or nearly complete survival. Most defects mandating unconventional perfusion flap reconstruction were caused by trauma (63.6 percent), especially of the hand and fingers (75.1 percent). The main complication of all types of flaps was a variable degree of necrosis (7.5 percent of all unconventional perfusion flaps presented marginal necrosis; 9.2 percent and 5.5 percent had significant and complete necrosis, respectively). There was a positive correlation between the rate of postoperative infection and the need for a new flap (Pearson coefficient, 0.405; p = 0.001). Flaps used to reconstruct the upper limb showed better survival than those transferred to the head and neck or to the lower limb (p < 0.001).

CONCLUSION

Unconventional perfusion flaps show high survival rates and should probably be used more liberally, particularly in the realm of upper limb reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

Syndactylizing arterialized venous flaps for multiple finger injuries

Multiple soft tissue finger defects in different shapes and locations are usually difficult to manage. Such defects commonly involve tendons and bones. Palmar soft tissue defects may also lead to vascular compromise. In this retrospective report, we report the results of seven patients with multiple soft tissue finger defects that were covered by syndactylizing arterialized venous flaps. Six of the patients suffered hot-pressing machine and crushing injuries, one patient had a rolling belt injury. All patients presented with soft tissue defects on palmar or dorsal sides involving at least two digits. The palmar forearm was donor site for all patients. At least one afferent artery and two efferent veins were selected for the anastomosis. Lengths of afferent and efferent veins were long enough to perform healthy anastomosis outside the injury zone. The afferent vessels were anastamosed to the digital arteries with the largest possible diameter or to the common digital arteries to maximize flow. The efferent veins were anastamosed to dorsal veins. Separations of the digits were performed after three weeks by longitudinal incisions. The mean follow-up period was 12 months. None of our patients suffered a flap loss. Syndactylizing arterialized venous flaps may be used for composite or single tissue reconstruction for multiple finger defects with satisfactory cosmetic and functional outcomes.

Free arterialised flow-through venous flap with venous anastomosis as the outflow (A-A-V flap) for reconstruction after severe finger injuries

Abstract For reconstruction of volar defects, an arterialised flow-through venous flap (A-A flap) can be used to restore the soft tissues and the digital artery at the same time. However, there have been reports that the circulation of this flap is inadequate. This study used a venous flap with only one venous anastomosis for the outflow of an A-A flap (A-A-V flap) to solve this problem. Six patients with defects of the finger soft tissues and digital artery after severe finger injuries were performed. The venous flap with a Y-shaped vein was harvested. The digital artery was reconstructed, after which the other proximal vein of this flap was anastomosed to the dorsal subcutaneous vein. The flap survived in all patients and histological examination of flap tissue showed a nearly normal architecture. This study describes the good results obtained with an A-A-V flap, and discusses the utility of our flap in comparison with previously reported venous flaps.

Artery-vein-artery venous flap for simultaneous soft-tissue repair and radial artery reconstruction: case report

We present a case of partial amputation of the forearm resulting in soft-tissue and radial artery defects that were simultaneously repaired using a large artery-vein-artery venous flap. The flap measured 4 × 11 cm, and we attribute its complete survival and long-term durability to the artery-vein-artery configuration.

Clinical applications of venous flaps in the reconstruction of hands and fingers

In recent years, the venous flap has been highly regarded in microsurgical and reconstructive surgeries, especially in the reconstruction of hand and digit injuries. It is easily designed and harvested with good quality. It is thin and pliable, without the need of sacrificing a major artery at the donor site, and has no limitation on the donor site. It can be transferred not only as a pure skin flap, but also as a composite flap including tendons and nerves as well as vein grafts. All these advantages make it an optimal candidate for hand and digit reconstruction when conventional flaps are limited or unavailable. In this article, we review its classifications and the selection of donor sites, update its clinical applications, and summarize its indications for all types of venous flaps in hand and digit reconstruction.

Bilateral upper extremity vascular injury as a result of a high-voltage electrical burn

High-voltage electrical burns are rare but cause devastating injuries, resulting in potential limb loss and major morbidity and mortality. These injuries are more insidious than flame burns in that the extent of the injury is not obvious at first glance. Damage to underlying muscle, nerve, and vessels may occur, resulting in limb-threatening ischemia and delayed hemorrhage. The management of such injuries remains controversial and can be challenging for the vascular and reconstructive surgeon. We present a case of high-voltage electrical injury to bilateral upper extremities resulting in limb-threatening ischemia, review the literature on the management of such injuries, and propose an algorithm to guide the management of these devastating injuries.

Late salvage of the ischemic finger after crush injury using flow-through flaps: case report

The progressive evolution and late salvage of a posttraumatic digit with poor vascularization has not been discussed in the literature. We report the cases of 3 patients whose fingers were rescued at referral 5 to 16 days after the traumatic event by restoring the arterial inflow by means of flow-through free flaps. All 3 fingers were compromised vascularly with patchy necrosis and absence of Doppler signal distal to the injury. All were salvaged. In our experience, in the setting of a posttraumatic digit with poor vascularization, it is possible to reverse impending necrosis by late revascularization. Frank infection or mummification is considered an irreversible state and a contraindication to salvage.

Optimizing the arterialized venous flap

BACKGROUND

Outcome of arterialized venous flaps is quite varied. The authors' initial experiments showed that a good vascular bed contributes significantly to survival of the flap. In continuation of these experiments, this study aimed to understand the influence of architectural variations on flap outcome.

METHODS

Fasciocutaneous flaps were designed on the ears of New Zealand rabbits, and the animals were randomized into four groups having flaps that used the larger anterior marginal vein (1.3 mm) or the smaller central vein (0.6 mm) for arterial inflow, with or without isolation of the flap from its bed with a silicone sheet. Flaps were observed for area of flap survival and vasculature was assessed by microangiography.

RESULTS

Using the smaller central vein for arterial inflow (n = 15), arterialized venous flaps had an excellent outcome, with good flap survival in 100 percent of the animals (survival of >85 percent of flap area), and a mean flap survival area of 99.4 +/- 1.6 percent. Even when neovascularization was prevented by isolation of the flaps (n = 14), 92 percent of central vein flaps showed good survival, with a mean flap survival area of 93.3 +/- 7.3 percent, which was significantly better than that of anterior marginal vein flaps (n = 22), which showed good flap survival in only 27 percent of the animals (mean flap survival area, 76.4 +/- 12.1 percent).

CONCLUSIONS

Survival of arterialized venous flaps is optimized by using smaller-caliber veins for inflow and reserving larger-caliber veins for outflow. This regulates inflow and avoids high blood pressure, and arterialized venous flaps behave as physiologic flaps do, by not relying on neovascularization for survival.

Finger Palmar Surface Reconstruction Using Medial Plantar Venous Flap

BACKGROUND

Because plantar anatomic features are similar to those of the palmar surface of the finger, palmar surface finger reconstruction using a medial plantar venous flap enables grasping without slippage, results in strength that can withstand friction, and provides a cushioning effect. Furthermore, sensory restoration is thought to be excellent due to the similarity of the tissues.

METHODS

We performed finger palmar surface reconstruction in 6 patients using venous flap without harvesting the medial plantar subcutaneous nerve branch and assessed the sensory restoration using a static 2-point discrimination test (s-2PD), moving 2-point discrimination test (m-2PD), and Semmes-Weinstein test (S-W test).

RESULTS

The mean s-2PD at 12 months after surgery was 8.6 mm, the mean m-2PD was 6.00 mm, and the S-W test score was 3.84-3.22

CONCLUSION

These findings indicate that sensory improvement can be obtained by finger palmar surface reconstruction without grafting of the medial plantar subcutaneous nerve branch to the digital nerve.

Flow-through flaps: A review of current knowledge and a novel classification system

Flaps have long been recognized as an essential tool for soft-tissue reconstruction. Flaps range in complexity from local to free and perforator flaps and can include a variety of composite tissues. The concept of a flow-through flap, in which both the proximal and the distal ends of the vascular pedicle of a free flap are anastamosed to provide blood flow to distal tissues, was first described by Soutar et al. in 1983. An uninterrupted arterial flow was established by Soutar et al. between the external carotid and distal facial artery via a radial forearm flap for head and neck reconstruction (Soutar et al., Br J Plast Surg 1983;36:1-8). Shortly thereafter, Foucher et al. were the first to report the reconstruction of an extremity with a simultaneous vascular defect by utilizing a radial forearm flow-through flap (Foucher et al., Br J Plast Surg 1984;37:139-148). The utility of the flow-through flap is now well established, and its indications for use continue to grow. The principle advantage of this flap is that it provides the opportunity for a single stage composite reconstruction of both soft tissue and vascular defects, making it particularly useful in the reconstruction of ischemic extremities and defects from oncologic ablations. Improvements in microsurgical equipment and techniques are making early difficulties with these flaps irrelevant, giving plastic surgeons opportunities to become more creative in the choices and uses of flow-through flaps. The literature consists mostly of case reports and series. The nomenclature used to describe the types of flow-through flaps is confusing and inconsistent. The purpose of this article is to provide an organized review of flow-through flaps and to classify these flaps based on their inflow, outflow, and the nature of their vascular conduit. Additionally, we have included a discussion on the physiology of these flaps, reviewed the current literature, and summarized the various types of flow-through flaps in a reference guide that can aid in flap selection.

The Bilobed Arterialized Venous Free Flap for Simultaneous Coverage of 2 Separate Defects of a Digit

We report a case of a 17-year-old patient who sustained multiple finger contusions on the left hand. After thorough debridement, the volar and dorsal defects of the middle finger were covered simultaneously with bilobed arterialized venous free flap from the left forearm. The flap was composed of 2 paddles, which were connected by a subcutaneous bridge containing a subcutaneous venous network. The subdermal plexus in the bridge was interrupted with no impairment of blood supply to the second cutaneous paddle. The flap survived completely with only temporary mild venous congestion. Excellent functional and cosmetic result was reached. We consider bilobed arterialized venous free flap as a useful option for coverage of concomitant volar and dorsal digital defects.