Perforator-Based Pedicled Cross-Leg Flaps in Pediatric Patients: A New Idea to Increase Flap Reach

The Autonomization Principle in Vascularized Flaps: An Alternative Strategy for Composite Tissue Scaffold In Vivo Revascularization

Autonomization is a physiological process allowing a flap to develop neo-vascularization from the reconstructed wound bed. This phenomenon has been used since the early application of flap surgeries but still remains poorly understood. Reconstructive strategies have greatly evolved since, and fasciocutaneous flaps have progressively replaced muscle-based reconstructions, ensuring better functional outcomes with great reliability. However, plastic surgeons still encounter challenges in complex cases where conventional flap reconstruction reaches its limitations. Furthermore, emerging bioengineering applications, such as decellularized scaffolds allowing a complex extracellular matrix to be repopulated with autologous cells, also face the complexity of revascularization. The objective of this article is to gather evidence of autonomization phenomena. A systematic review of flap autonomization is then performed to document the minimum delay allowing this process. Finally, past and potential applications in bio- and tissue-engineering approaches are discussed, highlighting the potential for in vivo revascularization of acellular scaffolds.

Reliability and Safety of Cross-Leg Free Latissmus Dorsi Muscle Flap in Reconstruction of Mutilating Leg Injuries Using End-to-Side Anastomosis

Background  Free tissue transfer is considered the gold standard option for the reconstruction of distal leg defects. Free tissue transfer using recipient vessels in the contralateral leg (cross-leg bridge) is a potential option to supply the flap if there are no suitable recipient vessels in the injured leg. Most studies have described this technique using end-to-end anastomosis which sacrifices the main vessel in the uninjured leg. This study evaluated the use of a cross-leg free latissimus dorsi muscle flap for the reconstruction of defects in single-vessel legs, using end-to-side anastomosis to recipient vessels in the contralateral leg without sacrificing any vessel in the uninjured leg. Methods  This is a retrospective study that included 22 consecutive patients with soft tissue defects over the lower leg. All the reconstructed legs had a single artery as documented by CT angiography. All patients underwent cross-leg free latissimus dorsi muscle flap using end-to-side anastomosis to the posterior tibial vessels of the contralateral leg. Results  The age at surgery ranged from 12 to 31 years and the mean defect size was 86 cm 2 . Complete flap survival occurred in 20 cases (91%). One patient had total flap ischemia. Another patient had distal flap ischemia. Conclusion  Cross-leg free latissimus dorsi muscle flap is a reliable and safe technique for the reconstruction and salvage of mutilating leg injuries, especially in cases of leg injuries with a single artery. As far as preservation of the donor limb circulation is concerned, end-to-side anastomosis is a reasonable option as it maintains the continuity of the donor leg vessels.

Parallel Cross-Leg Free Flap with Posterior Tibial Artery Perforator Pedicle Propeller Cable Bridge Flap for the Treatment of Lower Extremity Wounds: A Case Series Report

BACKGROUND

A cross-leg flap can be used to treat severely injured lower limbs but associated with complications. Herein, we describe a technique of a parallel cross-leg free flap combined with posterior tibial artery perforator pedicle propeller cable bridge flap for the treatment of lower extremity wounds.

METHODS

The artery and veins of the free flap are anastomosed to the contralateral posterior tibial artery and vein, respectively. The vascular pedicle is wrapped with a posterior tibial artery perforator pedicle propeller flap. The legs are allowed to remain in a straight, relaxed position which is maintained with a bandage or Kirschner wire placed at the distal limbs. Pedicle division is performed around 21 days after flap creation, and the posterior artery is re-anastomosed and pedicled flap returned to its original position.

RESULTS

From June 2017 to March 2020, 7 patients with lower extremity wounds and tissue loss received reconstruction with this method. The recipient vessels for all flaps were the posterior tibial artery and vein. The average operation time was 5 hours. The average time to ambulation was 4 weeks, and the average follow-up time was 13.7 months. All flaps survived, and limb salvage was successful in all patients. Patients were not uncomfortable with the limbs held in position until pedicle division, and there were no complications. At the final follow-up, the function of all limbs was normal, and the esthetic appearance was acceptable to all patients.

CONCLUSIONS

The method described overcomes the disadvantages of traditional cross-leg flaps for the treatment.

[Application of perforator propeller flap of lower limb in the treatment of foot and ankle defect in children]

OBJECTIVE

To investigate the effectiveness of perforator propeller flap of lower limb in the treatment of foot and ankle defect in children.

METHODS

The clinical data of 28 children with foot and ankle defect treated with perforator propeller flap of lower limb between January 2018 and January 2021 were retrospectively analyzed. There were 18 boys and 10 girls with an average age of 7.3 years (range, 6-14 years). There were 8 cases of traffic accident injury and 20 cases of chronic infection wound. The disease duration was 2-4 months, with an average of 2.8 months. After thorough debridement, the residual wound size ranged from 5 cm×4 cm to 9 cm×5 cm. Repairing was performed after 7-28 days of the infection in control. According to the location, size, and shape of the wound, the perforating vessels were located by ultrasonic Doppler, and the perforator propeller flap (area ranged from 6 cm×5 cm to 11 cm×6 cm) was designed and harvested to repair the wound. Flap transfer combined with free split-thickness skin graft covered the wound in 2 cases. The donor site was sutured directly (22 cases) or repaired with skin graft (6 cases).

RESULTS

Twenty-six flaps survived, of which 20 cases were in primary healing, and 6 cases had epidermal necrosis at the end of small paddle, which healed after dressing change. Necrosis occurred in 2 cases due to venous crisis which healed after anterolateral femoral flap free transplantation. Primary wound healing was achieved in donor site. All 28 children were followed up 6-24 months (mean, 10.5 months). The texture, shape, and motor function of the lower limb was satisfactory. At last follow-up, the American Orthopaedic Foot and Ankle Association (AOFAS) score was 89.8±8.0, which was significantly different from the preoperative score (79.6±10.4) ( t=-11.205, P<0.001); 20 cases were excellent, 6 cases were good, and 2 cases were poor, and the excellent and good rate was 92.8%.

CONCLUSION

The perforator propeller flap of lower limb in children has its own characteristics. It is a reliable method to repair the foot and ankle defect in children.