Large wounds reconstruction of the lower extremity with combined latissimus dorsi musculocutaneous flap and flow-through anterolateral thigh perforator flap transfer

Extended DIEP flap with bilateral anterior fascia based on unilateral perforator for lower extremity reconstruction

Complex soft tissue defects in the lower limb pose significant challenges for surgeons, especially when extensive coverage is needed. Free flaps are preferred for their reliable soft tissue, with the deep inferior epigastric perforator (DIEP) flap being particularly advantageous in middle-aged women due to its ample tissue and the ability to perform abdominoplasty at the donor site. However, its bulkiness can be an issue for lower limb reconstruction. We present two cases where the DIEP flap was used for lower limb reconstruction with immediate flap thinning. By employing a unique thinning method based on the vascular connection between perforators, we successfully extended the flap's use without needing to anastomose the pedicles. All flaps were well-vascularized with no complications, demonstrating that maintaining the anterior fascia between perforators optimizes the DIEP flap for reconstructive purposes.

Utilizing Perforator Propeller Flaps for Donor Site Closure: Harvesting Large Workhorse Flaps without Lingering Concerns

BACKGROUND

 Primary closure of donor sites following large flap harvest may not be feasible. The use of perforator propeller flap (PPF) in this setting is gaining popularity, successfully resurfacing the wound and lessening potential donor-site morbidity. In this study, we aimed to review our experience and outcomes using PPFs in donor-site coverage throughout the body.

METHODS

 A retrospective chart review was performed of all patients who underwent one or more PPFs surgery for donor site resurfacing between February 2009 and December 2021. Flap and defect characteristics were summarized. Postoperative complications and perioperative factors were analyzed.

RESULTS

 Fifty-five patients underwent donor-site reconstruction using 68 PPFs. Of the 55 primary donor sites, 44 were covered with a single PPF, 9 with two PPFs, and 2 with three PPFs. One flap experienced complete necrosis and four flaps experienced distal flap necrosis, leading to an overall complication rate of 9.1%. No risk factors were found to be statistically significantly associated with the complication. All secondary PPF donor sites were closed primarily. During the average follow-up period of 15.1 months, none of the patients developed contour deformities or functional impairments.

CONCLUSION

 The PPF technique can be safely and effectively used for donor-site closure with minimal complications. It greatly frees surgeons to harvest a large workhorse flap for demanding soft tissue defect reconstruction.

Individualized design program of multiple flaps for adapting different zones to repair large irregular wounds in children

OBJECTIVE

Management of large irregular wounds in children had been confusing plastic and reconstructive surgeons. Herein, this study was aimed to propose a new treatment method based on the principle of adapting different recipient zones to overcome the intractable wounds, simplifying and programing the design process of targeted flaps for covering large irregular soft-tissue defects.

PATIENTS AND METHODS

From January 2009 to December 2020, 31 children (9 girls and 22 boys) aged 3-16 years (mean 9.8 years) underwent multiple modular flaps with edge to edge splicing reconstruction of the lower extremities. All the wounds were large with non-adjacent defects and with or without a dead space. Several variants of flaps were harvested according to the needs and reconstruction requirements of patients.

RESULTS

A total of 71 flaps were harvested from 31 patients and all flaps donor sites received primary closure. Nine patients underwent split-thickness skin grafting, and three cases of flaps survived from vascular crisis by rebuilding the vessels and the rest accepting LD flap transplants. And five partial necrosis of the distal epidermis flaps recovered using skin grafting and dressing change. No major complication was encountered in other patients and donor sites, except one heel ulcer. During the follow-up (ranging from 16 to 38 months, mean 27.7 months), aesthetic and functional results of reconstructed limbs were satisfactory in all patients.

CONCLUSIONS

The Individualized design program of multiple flaps for adapting different recipient zones is an alternative for repairing large irregular soft-tissue defects in children, beneficial for plastic and reconstructive surgeons to simplify and program the process of designing and perform multiple flaps to achieve this goal.

LEVEL OF EVIDENCE

III, Retrospective.

Hydrogels containing KYNA promote angiogenesis and inhibit inflammation to improve the survival rate of multi-territory perforator flaps

BACKGROUND

A new spray adhesive (KYNA-PF127) was established through the combination of thermosensitive hydrogel (Pluronic F127) and KYNA, aimed to investigate the effect of KYNA-PF127 on multi-territory perforator flaps and its possible molecular mechanism.

MATERIALS AND METHODS

36 SD male rats with 250-300 g were randomly divided into 3 groups (n = 12): control group, blank glue group and KYNA-PF127 group. KYNA-PF127 hydrogel was prepared and characterized for its morphology and properties using scanning electron microscopy. CCK-8 assay, scratch wound assay, transwell assay, tube formation assay and Ki67 staining were used to study the effect of KYNA-PF127 on the proliferation, migration, and tube formation of HUVECs. VEGF and FGF2 were measured by qPCR to evaluate the angiogenesis capacity of HUVECs in vitro. In vivo, the effect of each group on the survival area of the cross-zone perforator flap was evaluated, and angiogenesis was evaluated by HE and immunofluorescence (CD31 and MMP-9). The effect of inflammation on skin collagen fibers was assessed by Masson. Immunohistochemistry (SOD1, IL-1β, TNF-α) was used to evaluate the effects of oxidative stress and inflammatory factors on multi-territory flaps.

RESULTS

KYNA-PF127 has good sustained release and biocompatibility at 25% concentration. KYNA-PF127 promoted the proliferation, migration, and angiogenesis of HUVECs in vitro. In vivo, the survival area of multi-territory perforator flaps and angiogenic capability have increased after KYNA-PF127 intervention. KYNA-PF127 could effectively reduce the oxidative stress and inflammation of multi-territory perforator flaps.

CONCLUSION

KYNA-PF127 promotes angiogenesis through its antioxidant stress and anti-inflammatory effects, and shows potential clinical value in promoting the survival viability and drug delivery of multi-territory perforator flaps.

Emodin activates autophagy to suppress oxidative stress and pyroptosis via mTOR-ULK1 signaling pathway and promotes multi-territory perforator flap survival

BACKGROUND

Multi-territory perforator flap reconstruction has been proven effective in treating large skin and soft tissue defects in clinical settings. However, in view of that the multi-territory perforator flap is prone to partial postoperative necrosis, increasing its survival is the key to the success of reconstruction. In this study, we aimed to clarify the effect of emodin on multi-territory perforator flap survival.

METHODS

Flap survival was assessed by viability area analysis, infrared laser imaging detector, HE staining, immunohistochemistry, and angiography. Western blotting, immunofluorescence assays, and real-time fluorescent quantitative PCR were performed to detect the indicators of oxidative stress, pyroptosis and autophagy.

RESULTS

After emodin treatment, the multi-territory perforator flap showed a significantly increased survival rate, which was shown to be closely related to the inhibition of oxidative stress and pyroptosis and enhanced autophagy. Meanwhile, the use of autophagy inhibitor 3 MA was found to reverse the inhibitory effects of emodin on oxidative stress and pyroptosis and weaken the improving effect of emodin on flap survival, suggesting that autophagy plays a critical role in emodin-treated flaps. Interestingly, our mechanistic investigations revealed that the positive effect of emodin on multi-territory perforator flap was attributed to the mTOR-ULK1 signaling pathway activation.

CONCLUSIONS

Emodin can inhibit oxidative stress and pyroptosis by activating autophagy via the mTOR-ULK1 pathway, thereby improving the multi-territory perforator flap survival.

Application of flow-through flaps for replantation after traumatic limb amputation according to the angiosome concept

OBJECTIVE

This study was performed to explore the treatment of the injury caused by traumatic limb amputation.

METHODS

From October 2002 to October 2021, 30 cases were enrolled in the present study. The reasons for injury were as follows: 8 cases with single hydraulic column crush injury, 12 cases with gear and wire rope stranding, 6 cases with belt avulsion injury, and 4 cases with carbon block smash injury. The present study application of a free or small saphenous vein bypass to reconstruct the injured artery and vein according to the concept of the angiosome model. The defective vessels were bridged with the axial vessels of a flow-through flap, such as a medial calf flap or anterolateral femoral flap, to construct an additional blood supply and drainage vein for the severed limb. The clinical data of 30 cases with traumatic limb amputation of the lower leg and ankle were retrospectively analyzed.

RESULTS

In all 30 cases of traumatic limb amputation, the replantation via the adoption of a flow-through flap was successful, and 85.6% of the patients remained in good postoperative condition. There were no symptoms of ischemia in the marginal segment after blood supply reconstruction of the transected limb by axial vascular bridging within the flap.

CONCLUSION

Via the adoption of microsurgical techniques, the blood supply to the transected limb can be reconstructed by bridging the defective vessels with the adoption of the axial vessels of the flow-through flap is a feasible and advanced treatment option.

The versatile thoracodorsal artery perforator flap for extremity reconstruction: from simple to five types of advanced applications and clinical outcomes

BACKGROUND

Application of the thoracodorsal artery perforator (TDAP) flap is known to be a popular and reliable method for extremity reconstruction. This manuscript presents our clinical outcomes in reconstructing soft tissue defects using simple and advanced TDAP flaps.

METHODS

From 2013 to 2022, 53 patients with a mean age of 23 years (ranging from 2 to 72 years) underwent reconstructive surgery with different patterns of free TDAP flaps, including chimeric TDAP flaps, double skin paddle TDAP flaps, flow-through TDAP flaps, conjoined TDAP flaps, and microdissected debulking TDAP flaps.

RESULTS

All TDAP flaps survived. The size of the TDAP skin paddle ranged between 5 × 3 and 25 × 10 cm2. Primary closure of the donor site was achieved in all patients in the simple application group, and one patient in the advanced application group underwent partial skin grafting. Partial flap loss occurred in one case in the simple TDAP flap group and four cases in the advanced application group. There was one case of flap bulkiness and two cases of scar hyperplasia in the simple TDAP flap group. The mean follow-up duration was 11 months (4-46 months).

CONCLUSIONS

The free TDAP flap, with five types of advanced applications, makes it versatile for reconstructing different kinds of soft tissue defects of the extremities that can be used to achieve individualized defect reconstruction, minimize donor site morbidities, and an aesthetic appearance.

Virtual surgical planning/3D printing assisted fibula osteoseptocutaneous flap combined with anterolateral thigh flaps for extensive composite oromandibular defects reconstruction: a retrospective study of case series

Oromandibular tumors or osteoradionecrosis often lead to extensive composite defects encompassing intraoral, bone and extraoral tissues. A single flap cannot simultaneously offer sufficient bone and soft tissue. The combination of free flaps could be a prospective approach to overcome the challenge. The study aims to assess the efficacy of virtual surgical planning (VSP) and 3D printing assisted fibula osteoseptocutaneous flap (FOSCF) combined with anterolateral thigh flaps (ALT) in reconstructing extensive composite defects in the oromandibular region. A retrospective analysis was conducted on 8 patients who underwent reconstruction using FOSCFs combined with ALTs. Post-surgical excision of the lesions, we obtained mean values for the defects of intraoral soft tissue, bone, extraoral soft tissue, namely, being 42.7 cm2, 96 mm, and 68.9 cm2. The mean surgical procedures took 712.5 min. A total of 16 flaps were harvested and transplanted for the 8 patients, with all successfully surviving. Postoperatively, complications manifested as localized intraoral infections in 2 cases, intermuscular vein thrombosis in another 2 cases, and pulmonary infections in 2 patients. Two patients unfortunately experienced tumor recurrence, at 12 and 3 months post-operation respectively. For the surviving 6 patients, the average follow-up period was 12.2 months. Regarding patient satisfaction, one expressed dissatisfaction with the contour of the mandible, and two exhibited moderate trismus. Objective assessments identified 1 case of oral incontinence and 2 cases where external flap contractures were observed. All 8 patients experienced restoration of masticatory function and were able to consume a soft diet within a month post-surgery. VSP/3D printing assisted FOSCFs combined with ALTs can be performed safely to reconstruct the extensive composite tissue defects in our study, with desirable esthetic and functional results, and it is a reliable option in selecting patients with defects involving multiple tissue types. However, the benefits of this method needed more cases to validate.

Anterolateral thigh flow-through flap: A versatile method for reconstruction of complex extremity defects

BACKGROUND

Flow-through flaps have been widely applied only for the reconstruction of complex defects in the extremities because they can be used for arterial reconstruction and soft tissue coverage simultaneously. This report attempts to fully demonstrate the role of the anterolateral thigh (ALT) flow-through flap as a versatile method for reconstructing complex defects in the extremities.

METHODS

From February 2011 to March 2017, we retrospectively analyzed the use of a reconstructive surgical technique based on the ALT flow-through flap to treat complex extremity defects in 87 patients (trauma, n = 79; diabetic ulcers, n = 5; squamous cell carcinoma, n = 3). Emergency surgery was performed in 12 patients to bridge a major artery gap and was followed by elective reconstruction in the remaining patients. Applications of the ALT flow-through flap included bridging major artery gaps, preserving recipient blood vessel integrity, reconstructing blood vessel continuity, protecting vascular anastomoses, avoiding difficult end-to-side anastomoses in the recipient area, and balancing blood flow, as well as combined application with an additional flap.

RESULTS

The flap size ranged from 6 × 3 cm to 17 × 9 cm. ALT flow-through flaps were used in combination with an additional flap (n = 4) and in vascular reconstruction (n = 83). Three patients required of the microvascular anastomostic reexploration for venous congestion, total necrosis occurred in two patients, and partial necrosis occurred in one patient. At the donor site, there were three cases of infection and two cases of wound dehiscence. At the recipient site, one case of infection and two cases of wound dehiscence were observed. One patient presented with deep infection secondary to renal failure and underwent amputation. During the follow-up period (range, 1-33 months), all other flaps (84 cases) survived uneventfully, with normal texture and color.

CONCLUSION

The ALT flow-through flap plays many roles as it is a versatile method for reconstructing complex defects of the extremities and serves various other clinical purposes.

Simultaneous sequential anterolateral thigh free flaps with interposition comitant vein graft for one-stage lower extremity reconstruction: A case report

Developments in the microsurgery have made perforator fasciocutaneous free flaps more popular in lower extremity reconstructions. They have acceptable donor site morbidities when compared to traditional methods. However; there are some possible limitations with these flaps such as anatomical variations and insufficiency to cover large and/or complex defects with a single flap. Anterolateral thigh flap (ALT), which has proven its advantages in the reconstruction of many regions of the body, is one of the versatile perforator fasciocutaneous flap options. We present our experience of using sequential double ALTs for complex lower extremity reconstruction. A 44-year-old patient, who had a history of multiple traumas as a result of a traffic accident, had interconnected anterior tibial (6 × 4 cm) and bimalleolar defects (4 × 4 cm, 4 × 5 cm) in his left lower extremity. Double ALT flaps (16 × 9 cm, 17 × 10 cm) were used to reconstruct three individual defects. The posterior tibial artery was the only uninjured artery perfusing the lower extremity, so the already occluded anterior tibial artery was chosen as the recipient to avoid disturbing the posterior tibial vessels. The dominant comitant vein of one of the flaps was leaving the pedicle too early and following an aberrant path with increased diameter. As it was understood that the other comitant vein had poor drainage, it was taken as an interposition vein graft to lengthen the dominant aberrant vein. The two flaps were customized as one by flow-through anastomoses on the operating table. The anterior tibial artery was washed and debrided distal to proximal until arterial spurting was seen. At the distance of 8 cm superior, the artery was found as feasible and anastomoses were performed. The proximal flap was inset vertically and the distal flap was inset on the horizontal axis to reach the bilateral malleolar defect. No complications were observed in both flaps. The patient was followed-up for 8 months. Despite the successful reconstruction, the patient is still unable to walk unaided due to multiple traumas and the rehabilitation process continues. We believe that the use of sequential double ALT may be a useful alternative to reconstruct large lower extremity defects with minimal donor site morbidity when a suitable single recipient vessel is available.

Anatomical View of Thoracodorsal Artery Variants Using Computed Tomography Angiography

BACKGROUND

 The latissimus dorsi (LD) muscle has a dominant pedicle with one thoracodorsal artery and receives sufficient blood by segmental circulation through several perforators. Thus, it is widely used in various reconstructive surgeries. We are reporting on the patterns of the thoracodorsal artery analyzed by chest computed tomography (CT) angiography.

METHODS

 We analyzed the preoperative chest CT angiography results of 350 patients scheduled to undergo LD flap breast reconstruction following complete mastectomy for breast cancer between October 2011 and October 2020.

RESULTS

 A total of 700 blood vessels were classified according to the Kyungpook National University Plastic Surgery-Thoracodorsal Artery (KNUPS-TDA) classification: 388 (185 right and 203 left), 126 (64 right and 62 left), 91 (49 right and 42 left), 57 (27 right and 30 left), and 38 (25 right and 13 left) vessels were classified as type I, type II, type III, type IV, and type V, respectively. Among 350 patients, 205 patients showed matching types for left and right vessels, whereas 145 patients showed mismatching types. For 205 patients with matching types, the distribution by type was 134, 30, 30, 7, and 4 patients with type I, type II, type III, type IV, and type V, respectively. For 145 patients with mismatching types, the distribution by different combinations was 48, 25, 28, 19, 2, 9, 7, 3, 1, and 3 patients with type I + type II, type I + type III, type I + type IV, type I + type V, type II + type III, type II + type IV, type II + type V, type III + type IV, type III + type V, and type IV + type V, respectively.

CONCLUSION

 While there is some diversity in the vascular anatomical structures of the LD flap, the dominant vessel can be found in a similar location in almost all cases and no flap had absence of a dominant vessel. Therefore, in surgical procedures using the thoracodorsal artery as the pedicle, preoperative radiological confirmation is not absolutely necessary; however, due to variants, performing the surgery with an understanding of this aspect should lead to good outcomes.

Flow through fibula and fasciocutaneous free flaps in oromandibular reconstruction

INTRODUCTION

The osteocutaneous fibula is a workhorse flap for oromandibular reconstruction. Skin paddles not only perform soft tissue reconstruction but also serve as a monitor for the fibula. In cases where the skin paddle cannot be harvested as desired due to variations, two challenges arise, such as fibula follow-up and the need for a second free flap so recipient. Moreover, there may not be enough recipient vessels for the double flaps in the neck. This report aimed to address the difficulties mentioned above with the use of flow-through free flaps in composite oromandibular reconstructions.

PATIENTS AND METHODS

Between 2019 and 2021, five (three Female, two Male) patients underwent flow-through technique as free fibula and fasciocutaneous flaps due to variations in fibular skin paddle or insufficiency of recipient vessels in the neck. Ages of patients were between 45 and 75 years. Four patients underwent surgery for tumor and one patient for the result of radionecrosis. ALT, chimeric ALT, and RFFF were selected as second free flaps.

RESULTS

The size of the fasciocutaneous flaps ranged from 6 × 4 cm to 14 × 11 cm. Mandibular defects ranged from 6 to 16 cm. 1 venous occlusion occurred post-op 1st day and was salvaged. One hematoma and one wound dehiscence occurred postoperatively and were salvaged successfully. One Partial tongue necrosis occurred due to previous radiotherapy and additional tumor surgery. No additional complication occurred. All flaps survived. Follow-up period was between 3 months and 2 years. Patient who had tongue necrosis experienced swallowing and speech difficulty and Percutaneous endoscopic gastrostomy tube was placed post-operative 2 months. Functional finale outcomes were successful for other patients.

CONCLUSION

Flow-through technique provides fibula monitoring with avoiding to find second recipient. Customizing free flaps under more favorable conditions as on the operation table before fixation of the bone can be a useful approach.

The turbocharged wide anterolateral thigh perforator flap to reconstruct massive soft tissue defects in traumatized lower extremities: A case series

BACKGROUND

Extensive traumatic soft tissue defects in the lower extremities typically require complete coverage of exposed bone because inadequate coverage, such as partial flap loss, may result in bony infection and ultimately lead to limb salvage failure. To achieve complete coverage of these defects, we used the wide anterolateral thigh perforator flap in which the turbocharging procedure augments the blood flow. Herein, we describe our turbocharging technique and discuss its effectiveness.

METHODS

From January 2014 to December 2020, the turbocharged wide ALTP free flaps were used to treat 13 patients with massive traumatic soft tissue defects in the lower extremities, ranging in size from 22 × 10 cm2 (220 cm2) to 21 × 17 cm2 (357 cm2) (mean, 270 cm2). All ALTP flaps were supplied by perforators from both the transverse branch of the lateral circumflex artery (TB-LCFA) and descending branch of the lateral circumflex artery (DB-LCFA) simultaneously. The turbocharging procedure by connecting the TB-LCFA to a side branch of the DB-LCFA was carried out in all these flaps. A retrospective review of medical records for each patient was performed.

RESULTS

The size of the transferred ALTP flap ranged from 23 × 12 cm2 (276 cm2) to 23 × 19 (437 cm2) (mean, 331 cm2). The total number of perforators included in the flaps was three on average. All ALTP flaps survived completely without partial necrosis. The postoperative course was uneventful except for two cases with minor complications, including hematoma and partial necrosis of the recipient's skin.

CONCLUSION

Free transfer of the turbocharged wide ALTP flap can be a reliable and effective reconstructive method to obtain complete coverage of extensive traumatic soft tissue defects in the lower extremities and achieve successful limb salvage.

Resurfacing of lower extremities: Versatility of thigh flap as pedicle extension graft with consecutive thoracodorsal artery perforator-based flap

BACKGROUND

For successful microsurgical reconstruction using free tissue transfer, healthy recipient vessels must be obtained from outside the zone of injury. Securing an appropriate length pedicle length is also essential, and various techniques for lengthening a vascular pedicle have been developed. Herein, we present our experience using the descending branch (DB) of the lateral circumflex femoral vessels (LCFVs) with a thigh flap as an extender graft for consecutive second flap.

METHODS

We reconstructed the complex and vessel-depleted defects of nine patients. The mean age was 47.6 years. The defects were located in the lower leg in four patients, in the perineum in two patients and in the forearm in three patients. The two patients who suffered from Fournier's gangrene underwent a pedicled anteromedial thigh (pAMT) flap with the DB of the LCFVs and seven patients, five who suffered high-energy trauma and two who had scar contracture, underwent a free anterolateral thigh (ALT) flap with the distal run-off DB of the LCFVs. In all patients, second consecutive free latissimus dorsi or thoracodorsal artery perforator flaps were prepared and the thoracodorsal vessels of the second flap were anastomosed to the distal DB of the LCFVs.

RESULTS

The total length of the thigh flap pedicles measured from both ends of the DB of the LCFVs varied from 15 to 20 cm, which was sufficient for use as a vascular conduit. Of the 18 flaps, 17 survived completely without any complications and 1 pAMT flap showed partial necrosis, which was covered with a perineal perforator-based island flap. The mean follow-up period was 16.7 months. Unfortunately, one patient, who suffered a total amputation below the knee and had replantation surgery, underwent amputation due to venous congestion in the distal leg. However, the previous two flaps survived and were used for coverage of the stump.

CONCLUSIONS

Using a thigh flap as a vascular extender graft for second flap may be an alternative option in vessel-depleted reconstructions.

Reconstruction of Large Soft Tissue Defects in the Distal Lower Extremity: Free Chain-Linked Bilateral Anterolateral Thigh Perforator Flaps versus Extended Latissimus Dorsi Musculocutaneous Flaps

Background: Reconstruction of the large soft-tissue defects in the lower extremity still constitutes a challenge for plastic surgeons. This retrospective study was conducted to compare the surgical and clinical outcomes of the chain-linked bilateral anterolateral thigh perforator flaps and extended latissimus dorsi musculocutaneous flap in the reconstruction of the large soft tissue defects of the lower extremity. Methods: From January 2012 to December 2021, 34 patients aged between 20 and 66 years received chain-linked bilateral anterolateral thigh perforator flaps (15 cases) or extended latissimus dorsi musculocutaneous flaps (19 cases) for the reconstruction of extensive soft-tissue defects in the lower extremity. The two groups were homogeneous in terms of age, etiology, comorbidities, and flap area. In addition, the intraoperative data, outcomes, complications, and long-term follow-up results were collected and analyzed. Results: The extended latissimus dorsi musculocutaneous flap group had a shorter operation time (271.8 ± 59.5 min vs. 429.6 ± 51.9 min), harvest time (58.9 ± 24.8 min vs. 152.7 ± 41.4 min), and anastomosis time (27.2 ± 10.4 min vs. 53.7 ± 8.1 min) than the chain-linked bilateral anterolateral thigh perforator flaps group (p < 0.05). Based on patient self-assessment, the donor site temporary muscle weakness in the extended latissimus dorsi musculocutaneous flap group was significantly more than that in the chain-linked bilateral anterolateral thigh perforator flaps group (p < 0.05). Conclusion: Both methods can repair large defects and restore the function of the injured limbs at a single stage. However, considering the operation time and flap-harvesting time, the authors recommend the extended latissimus dorsi musculocutaneous flap, especially for those who cannot tolerate a prolonged surgery.

Melatonin Improved the Survival of Multi-Territory Perforator Flaps by Promoting Angiogenesis and Inhibiting Apoptosis via the NRF2/FUNDC1 Axis

Background: Multi-territory perforator flaps are a reconstructive measure for repairing large soft tissue defects caused by tumors or trauma. However, the use of these flaps in clinical practice has been restricted due to the uncertain blood supply. Therefore, promoting the survival of the multi-territory perforator flap is critical for clinical repair and reconstruction. In our study, we explored the effects of melatonin (MLT) on multi-territory perforator flaps and the possible molecular mechanisms.

Materials and Methods: Seventy-two Sprague–Dawley rats (250–300 g) were randomly divided into 3 groups (n = 24): Control, MLT and MLT + ML385 groups. First, we assessed the survival area of the flap, followed by the micro-vessel density and CD31-positive vessel expression. Apoptosis of the skin flap under immunofluorescence and expression of the apoptosis-related proteins Bcl-2, Bax and Caspase3 were measured. Additionally, angiogenesis of the skin flaps was shown by angiography, and NRF2 and FUNDC1 mRNA and protein expression was detected by real-time PCR and western blotting.

Results: The results showed that MLT increased the survival area of the multi-territory perforator flap, which was related to increased angiogenesis and decreased apoptosis. We also found that mRNA and protein of NRF2 and FUNDC1 levels were significantly increased after MLT treatment, and an NRF2 inhibitor reversed the ability of MLT to enhance multi-territory perforator flap survival, promote angiogenesis and inhibit apoptosis and reduced FUNDC1 protein expression.

Conclusion: MLT promoted angiogenesis and inhibited apoptosis to promote the survival of multi-territory perforator flaps, which may be regulated via the NRF2/FUNDC1 axis.

[Application of anterolateral thigh bridge flap with free skin graft wrapping vascular bridge in complex calf soft tissue defects]

Objective

To explore the effectiveness of anterolateral thigh bridge flap with free skin graft wrapping vascular bridge in repairing complex calf soft tissue defects.

Methods

The clinical data of 11 patients with complex calf soft tissue defects between April 2018 and October 2021 were retrospectively analyzed, including 9 males and 2 females, aged 11-60 years, with a median age of 39 years. There were 8 cases of calf soft tissue defect caused by traffic accident, and 3 cases of calf skin infection caused by chronic osteomyelitis. The skin and soft tissue defects ranged from 10 cm×8 cm to 35 cm×10 cm after thorough debridement and accompanied with bone and tendon exposure. There was only one main vessel in calf of 9 cases and no blood vessel that could be anastomosed with the flap vessel could be found in the recipient site of 2 cases. The anterolateral thigh skin flap (the flap size ranged from 12 cm×10 cm to 37 cm×12 cm) was taken to repair the soft tissue defect. The donor site of the flap was treated with direct suture (8 cases) or partial suture followed by skin grafting (3 cases), and the vascular bridge was wrapped with medium-thickness skin graft.

Results

The flaps of 11 patients survived completely without necrosis, infection, and vascular crisis. The blood supply of the vascular bridge was unobstructed and the pulse was good. The color of the medium-thickness skin graft were ruddy. All 11 patients were followed up 2-40 months, with an average of 19.4 months. The flaps healed well with the surrounding tissues without obvious exudation and color difference. The flaps had normal color and temperature, good blood supply, and soft texture. The shape of the flap and calf contour were satisfactory and the function of the limb recovered well. The donor area of thigh flap healed by first intention without obvious scar formation. The donor area of skin healed well with a longitudinal oblong scar only and the appearance was satisfactory.

Conclusion

The anterolateral thigh bridge flap transplantation with free skin wrapping vascular bridge is an effective method for the treatment of complex calf soft tissue defects.

The triple conjoined scapular-latissimus dorsi-groin flap for reconstruction of long lower extremity degloving injury: A case report

Since the introduction of the angiosome concept, many attempts have been made to push the dimensional limits of free tissue transfers. While initially limited by the boundaries of random vascularization of adjacent angiosomes, wider flaps were transferred by combining contiguous source vessels. Combined flaps, either chimeric or conjoined, represent nowadays the largest reconstructive options in the human body. This is the first report of a triple conjoined free flap with two vascular anastomoses, able to cover the anterior surface of the entire lower limb, representing the longest flap ever reported in history. A 43-year-old woman sustained a car accident as a pedestrian and presented with a massive circumferential degloving injury of the right lower limb. Femoral displaced shaft fracture and Gustilo type IIIb tibial fracture were diagnosed with emergent CT scan. A myocutaneous latissimus dorsi flap was planned, conjoined with the scapular flap to obtain a thick and large cover for the knee, and with a groin flap, to cover for the foot. Descending branch of lateral circumflex femoral artery and anterior tibial artery at the dorsum of the foot were selected as recipient vessels. Donor site was closed primarily. All flaps survived and no immediate nor late complications were reported. Follow up was 3 months. The triple conjoined flap can be considered a safe and useful reconstructive tool in severe degloving injuries of the lower limb, allowing the coverage of a large surface of the lesion with a single operation and without increasing the donor site morbidity.