Algorithm for Free Perforator Flap Selection in Lower Extremity Reconstruction Based on 563 Cases:

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.

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.

Microvascular Free Flap Reconstruction of Thigh Defects After Tumor Resection in the Setting of Radiation

BACKGROUND

Soft tissue reconstruction of the thigh defects can usually be achieved with local options. Free tissue transfer may be indicated in very large defects with exposed vital structures and/or a history of radiation therapy where the healing potential of local option is poor. In this study, we evaluated our experience on microsurgical reconstruction of oncological and irradiated thigh defects to assess the risk factors for complications.

METHODS

Institutional review board-approved retrospective case series study using electronic medical records from 1997 to 2020 was conducted. All patients with irradiated thigh defects derived from oncological resections who underwent microsurgical reconstruction were included. Patient demographics and clinical and surgical characteristics were recorded.

RESULTS

Twenty free flaps were transferred in 20 patients. Mean age was 60 ± 11.8 years, and median follow-up time was 24.3 months (interquartile range [IQR], 71.4-9.2 months). The most common type of cancer was liposarcoma (n = 5). Neoadjuvant radiation therapy was performed in 60%. Most commonly used free flaps were latissimus dorsi muscle/musculocutaneous flap (n = 7) and anterolateral thigh flap (n = 7) Nine flaps were transferred immediately after resection. Overall, 70% of arterial anastomoses were end-to-end, whereas 30% were end-to-side. Deep femoral artery branches were chosen as the recipient artery in the 45%. Median length of hospital stay was 11 days (IQR, 16.0-8.3 days), and median time to start weight-bearing was 20 days (IQR, 49.0-9.5 days). All were successful except for 1 patient who required additional pedicled flap coverage. The overall major-complication rate was 25% (n = 5, hematoma = 2, venous congestion requiring emergent exploration surgery = 1, wound dehiscence = 1, surgical site infection = 1). Cancer recurred in 3 patients. One required amputation due to cancer recurrence. Age (hazard ratio [HR], 1.14; P = 0.0163), tumor volume (HR, 18.8; P = 0.0006), and resection volume (HR, 2.24; P = 0.0019) were statistically significantly associated with having a major complication.

CONCLUSIONS

Based on the data, microvascular reconstruction of irradiated post-oncological resection defects shows high flap survival rate and success. Given the large size of flap required, the complex nature and size of these wounds, and history of radiation, wound healing complications are common. Despite this, free flap reconstruction should be considered in irradiated thighs with large defects. Studies with larger cohort and longer follow-up are still required.

Aesthetic Considerations in Extremity Salvage and Reconstruction

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Have an in-depth understanding of the functional and aesthetic requirements of lower extremity reconstruction. 2. Describe the considerations for achieving an optimal aesthetic outcome in the primary reconstruction settings. 3. Describe modalities of secondary flap revision for achieving an optimal aesthetic outcome.

SUMMARY

Significant advancements have been made in the management of lower extremity reconstruction since Dr. Taylor's seminal case in 1973. Improvements in our understanding of vascular anatomy and evolution of microsurgical techniques have allowed for an ever-increasing array of free tissue transfer options for lower extremity reconstruction. The resulting expertise has engendered a paradigm shift toward the reconstructive elevator approach, with increased emphasis on cosmetic results. In the primary setting, aesthetic considerations play an important role in precoverage wound preparation, flap selection, and harvest technique, with the goal of achieving excellent like-with-like reconstruction at the time of initial surgery. Flap selection should be made to best match the three-dimensional architecture of the wound, and take into account the defect thickness, flap thickness, flap composition, and pedicle length. Primary flap thinning and harvest in the superficial fascial plane has been shown to be an effective modality to address excess adiposity and improve contour. Despite these efforts, secondary procedures are often required to optimize the limb's final appearance and functional outcomes, particularly in the foot and ankle region. These include debulking, liposuction, and staged excisions. As the field of limb salvage keeps evolving, aesthetics will continue to play an important role in extremity reconstruction planning and execution.

Maximizing the Versatility of Thin Flap from the Groin Area as a Workhorse Flap: The Selective Use of Superficial Circumflex Iliac Artery Perforator (SCIP) Free Flap and Superficial Inferior Epigastric Artery (SIEA) Free Flap with Precise Preoperative Planning

BACKGROUND

 This study aimed to evaluate the usefulness of the selective use of the superficial circumflex iliac artery perforator (SCIP) and the superficial inferior epigastric artery (SIEA) flap as a workhorse flap from the groin area with precise preoperative surgical planning.

METHODS

 A total of 79 free flap reconstructions were performed in the study period; 35 SCIP free flaps and 19 SIEA free flaps were performed in the study period. Detailed preoperative surgical planning was performed using computed tomography (CT) angiography and color Doppler ultrasound. Detailed anatomical information of the flaps and reconstructive outcomes were evaluated.

RESULTS

 Flap characteristics between SCIP free flaps and SIEA free flaps were similar. The average transverse distance of the perforator from anterior superior iliac spine was 15.91 cm in SCIP free flaps and 43.15 cm in SIEA free flaps. The overall flap success rate was 96.4%. Majority of the patients achieved satisfactory contour without debulking surgery. Donor site morbidity was minimal with one case of wound dehiscence.

CONCLUSION

 The selective use of the SCIP and SIEA free flap in groin area is a safe and useful technique. The surgical outcomes were reliable and similar between the SCIP and SIEA free flaps. Preoperative vascular planning using CT angiography and color Doppler ultrasound is essential for selecting the proper flap.

The Use of Thermal Imaging in Free Perforator Flap Planning

Background. Preoperative planning and design of microsurgical perforator flaps are the main steps for successful operation. The aim of this study was to determine the concordance between thermographic images obtained with smartphone thermal imaging camera and hand-held Doppler in the anterolateral thigh flap (ALT) model. Methods. A concordance study of diagnostic tests was carried out in Hospital of Lithuanian University of Health Sciences Kaunas Clinics, Plastic and Reconstructive Surgery Department during 2020–2022. Patients’ who were scheduled to undergo reconstruction with ALT flap and healthy volunteers were included in the study. Dynamic thermal images were performed with smartphone thermal camera FLIR One PRO in the typical ALT flap territory. The number and distance of hotspots in the thermogram with respect to anterior superior iliac spine were recorded in the study protocol. Later, the examination was repeated with hand-held Doppler and the control of hotspot was performed. Sensitivity, specificity and concordance index calculations were performed. Statistical analysis was performed using IMB SPSS 23.0. Results. A total of 100 ALT flap territories were examined. 266 hotspots were detected with thermal imaging and 275 perforators with hand-held Doppler. In 96.6% of cases, hotspots detected by a thermal camera were confirmed by hand-held Doppler as perforators. The sensitivity and specificity of thermography for the detection of perforators with respect to the hand-held Doppler were 93.5% and 96.9% respectively. The measure of concordance kappa index was 0.095 (p = 0.001). Conclusion. Smartphone thermal imaging have a high concordance with hand-held Doppler in perforator mapping, thus could be considered a useful adjunct to conventional methods.

Association of Dual Venous Anastomosis with Reduced Risks for Flap Congestion in Microsurgical Lower Extremity Reconstruction: A Multicenter Study

BACKGROUND

 Flap congestion related with venous thrombosis is a major cause for microsurgical lower extremity reconstruction failure. Conducting dual venous anastomosis has been suggested to reduce risks for the adverse outcomes; however, its efficacy remains controversial. This study evaluated a potential association of dual venous anastomosis with the development of flap congestion in diverse clinical situations.

METHODS

 This multicenter study included patients who underwent microsurgical lower extremity reconstruction at two institutions. They were divided into two groups based on the number of venous anastomoses-single and dual groups. Their perfusion-related complications (PRCs), including total/partial flap loss, arterial or venous insufficiency, and emergent reoperation, were compared. Independent association of the number of venous anastomoses with the outcomes was evaluated. Further analyses were conducted using propensity score matching.

RESULTS

 In total, 225 cases were analyzed, of which 92 were included in the single group and the other 133 in the dual group. The two groups had generally similar baseline characteristics. The dual group presented significantly lower rates of PRC, including total/partial flap loss, flap congestion, and emergent reoperation. Multivariable analyses showed that conducting dual venous anastomoses was associated with reduced risks for the development of overall PRC and flap congestion. These associations were more prominent when restricting analyses for cases with chronic wound and trauma (vs. oncologic defects). Similar associations were observed in the propensity score matching analysis.

CONCLUSION

 Conducting dual venous anastomosis seems associated with reduced risks for flap congestion in microsurgical lower extremity reconstruction, especially for cases with unfavorable conditions.

Comparison of "complications" and functional outcome of anterolateral thigh flap and sural neurofasciocutaneus flap for foot and ankle reconstruction: A single center cohort study

BACKGROUND

Skin and soft-tissue defects around the foot and ankle remain a challenge for orthopedic and plastic surgeons. Anterolateral thigh (ALT) flap and sural neurofasciocutaneous (NFC) flap are both used to reconstruct lower-extremity soft-tissue defects. The purpose of this study was to compare outcomes of the two flaps and attempt to provide an optimal strategy.

METHODS

A retrospective study was conducted, reviewing data from 93 patients who underwent reconstruction of wounds around the foot and ankle with ALT flap (42 cases) or NFC flap (51 cases) from January 2014 to January 2020. Patients' demographics, characteristics of the defect, complications, cosmetic appearance, and functional outcome were analyzed, and statistical analysis was performed.

RESULT

There was no difference in gender and etiology; however, NFC flaps were more frequently used in elderly patients. Mean size of the flap in the ALT group was significantly larger in comparison with the NFC group. The ALT group had longer operation and hospitalization time than the NFC group (P < 0.05). The incidence of partial necrosis in ALT group was significantly lower than that in NFC group, while its general complications rate was higher. In long-term follow-up, esthetic appearance of the reconstructed site was comparable in both groups, the ALT group had a higher ratio of revision surgery. Moreover, the ALT group showed better overall esthetic outcomes in the donor site.

CONCLUSIONS

The study showed that anterolateral thigh flaps in wound coverage of foot and ankle achieved better outcomes than neurofasciocutaneous flaps in terms of recipient benefits and donor-site compromise with a special indication for larger and more distally located defects.

Free versus Pedicled Flaps for Lower Limb Reconstruction: A Meta-Analysis of Comparative Studies

Background: Free and pedicled flaps are both valuable surgical strategies for lower limb reconstruction. Evidence that compares both techniques is scarce. Our aim is to synthetise all the comparative studies by conducting a meta-analysis to identify post-operative outcomes. Method: A systematic review of pubmed, EMBASE, Cochrane library, and Web of Science was conducted, aiming at articles comparing the outcomes of free versus pedicled flaps in lower limb reconstruction. A pooled analysis with the Mantel and Haenszel methods and random effect analysis provided results as a risk ratio with a 95% confidence interval. Results: 10 retrospective studies were selected. While the flap necrosis rate did not differ significantly between techniques (RR 1.35, 95%CI 0.76–2.39, p = 0.31), the partial flap necrosis rate was significantly lower in free flaps (RR 0.45, 95%CI 0.22–0.91, p = 0.03). The overall complication rate (RR 0.83, 95%CI 0.64–1.07, p = 0.16) and revision surgery rate (RR 1.38, 95%CI 0.55–3.50, p = 0.49) did not differ significantly. No significant difference was found in the high aesthetic satisfaction rate (RR 1.76, 95%CI 0.57–5.41, p = 0.32) and post-operative infection rate (RR 0.85, 95%CI 0.55–1.33, p = 0.48). Conclusion: Despite important variability in the choice of flaps and outcomes reported among studies, free and pedicled flaps appear to be reliable surgical strategies for lower limb reconstruction with similar surgical outcomes.

A Retrospective Case Series on Free Flap Reconstruction for Ischemic Diabetic Foot: The Nutrient Flap Further Explained

BACKGROUND

This retrospective case series compares the outcomes and postoperative oxygen levels in patients who underwent free flap versus primary closure/local flap reconstruction for ischemic diabetic foot wounds to determine the influence of free flap on the surrounding ischemic tissues. The authors hypothesized that the free flap would benefit the surrounding ischemic tissue as a nutrient flap by increasing the tissue oxygen content.

METHODS

The patients were divided into two groups: group 1 underwent free flap reconstruction, and group 2 underwent partial foot amputation with primary closure/local flap. Patient demographics, endovascular intervention, surgical outcome, postreconstruction intervention, and prereconstruction and postreconstruction transcutaneous oximetry were analyzed.

RESULTS

Among 54 patients, 36 were in group 1 and 18 were in group 2. There were no differences in patient demographics between the two groups. All patients had successful angioplasty. Statistical significance was noted in postreconstruction intervention in which group 2 required 2.8 ± 2.9 débridements (versus 1.2 ± 2.5 for group 1) and seven of 18 below-knee amputations (versus three of 36 for group 1) (p < 0.05). Transcutaneous partial pressure of oxygen levels were significantly higher in group 1 at 6 months after reconstruction (61.6 ± 7.5 versus 32.6 ± 5.8 mmHg) (p < 0.01).

CONCLUSION

This study shows that the role of the free flap in ischemic diabetic limb may expand beyond that of providing coverage over the vital structures, and it supports the use of the free flap as a nutrient to increase oxygen content in the ischemic diabetic foot.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Using Duplex Ultrasound for Recipient Vessel Selection

INTRODUCTION

 Among the many factors involved in reconstructive microsurgery, identifying a good recipient vessel is one of the key elements leading to a successful result.

MATERIAL AND METHOD

 Multiple modalities have been used to identify recipient vessels from simple palpation of axial arteries to hand-held Doppler, duplex ultrasound, computed tomography angiograms, and other advanced techniques. Although these various modalities bring their own unique advantages, using the duplex ultrasound can provide far superior and real-time information based on the anatomy and physiology of the recipient vessel.

RESULT

 Duplex ultrasound is a valuable and powerful tool for reconstructive surgeons who are interested in performing microsurgery or supermicrosurgery.

CONCLUSION

 As we enter the era of individualized/customized reconstruction using superthin flaps, perforator-to-perforator anastomosis, and supermicrosurgery, understanding and becoming versatile with duplex ultrasound will be critical especially in choosing recipient vessels.

Are Perforators Reliable as Recipient Arteries in Lower Extremity Reconstruction? Analysis of 423 Free Perforator Flaps

BACKGROUND

Perforator flaps have revolutionized lower limb reconstruction by offering single-stage thin, pliable coverage with an excellent aesthetic match. Although anastomosis of the flap to a major artery remains the gold standard, perforator-to-perforator anastomosis has several advantages, including expedient recipient dissection and increased recipient options in vessel-depleted extremities. The aim of this study was to compare flap survival when a perforator or major artery was used as a recipient vessel.

METHODS

A retrospective cohort of free perforator flaps for lower limb reconstruction was reviewed. Demographics, comorbidities, vascular status, defect characteristics, operative details, and complications were recorded. Outcomes for perforator and major artery recipients were compared.

RESULTS

Four hundred twenty-three flaps were performed for various reasons using perforator flaps. The total limb salvage rate was 98.8 percent. Total and partial flap failure rates were 6.1 percent and 9.0 percent, respectively. Comparing perforator recipients [n = 109 (25.8 percent)] to major artery recipients [n = 314 (74.2 percent)], there was no significant difference in total (p = 0.746) or partial flap failure (p = 0.212). Significant factors between the groups included larger flap size with major artery recipients (p = 0.001) and shorter operative time when using a perforator recipient (p = 0.012).

CONCLUSIONS

Perforator-to-perforator anastomosis is a reliable option that affords equivalent rates of flap success compared to major artery anastomosis in lower extremity reconstruction. The authors advocate using a major artery recipient in defects where the axial vessels are easily accessible. A perforator recipient is a viable alternative in defects where access to the axial vessels is inconvenient and in patients with limited recipient options.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Modified lateral gastrocnemius myocutaneous flap with extended anterior and/or inferior boundary

There is little information regarding the boundaries of the lateral gastrocnemius myocutaneous (LGM) flap. The aim of this study was to introduce the modified technique of the LGM flap with extended anterior and/or inferior boundaries and its anatomical basis. Five fresh lower limb specimens were perfused and radiographed. Between December 2003 and August 2018, 27 modified LGM flaps with extended anterior and/or inferior boundaries were raised in 27 patients to reconstruct the soft tissue defects over the middle and upper leg, knee, and lower thigh. Both the lateral popliteal cutaneous artery and musculocutaneous perforators from the lateral sural artery had rich linked arteries communicating with the chain-linked arterial network around both the posterolateral intermuscular septum and the sural nerve, and they also had rich transverse communicating arteries connecting with the perifascial arterial network overlying the anterior compartment in the upper and middle calf. Continuous fascial arterial networks were extended up to the level at the intermalleolar line. Twenty-three flaps survived uneventfully, 2 flaps displayed distal de-epithelialization, and 2 flaps (7.41%) developed partial necrosis. Osteomyelitis was cured successfully in all patients, and no relapse of infection was encountered during the follow-up period. Multiple feeder arteries are the arterial anatomic basis of the modified LGM flap. The modified LGM flap with extended anterior and/or inferior boundaries is feasible, and the modified flap with extended anterior boundaries is safe and reliable.

Safety and Vascular Impact of Perforator Propeller Flaps during Distal Lower Limb Reconstruction

Background:

In distal lower limb defects, the paucity of local tissues dictates a free-flap (FF)-based reconstruction frequently. The propeller perforator flap (PPF) offers a good alternative when the patient or the limb or both are not fit for FF-based reconstruction. Also, in contexts of restricted healthcare resources, armed conflict scenarios, or during pandemics like the ongoing COVID-19 pandemic, PPF is considered a valuable alternative to free-flap-based reconstruction. Additionally, PPFs are less sacrificing in terms of major limb vessels and distal limb vascularity. Yet, the distal lower limb vascular impact for PPF-based reconstruction has not been studied before.

Methods:

In total, 23 patients with distal lower limb defects were reconstructed with PPFs. By using U/S arterial duplex, the peak arterial velocity (PA velocity) was measured pre and postoperatively in 15 (65.2%) out of the 23 patients. This measurement was done to the vessel segment distal to the used perforator.

Results:

An estimated 21 out of 23 flaps succeeded to reconstruct the patients’ defects safely and to give all patients stable coverage without further surgeries. Only two patients had flap failure, which was managed successfully through additional reconstruction sessions. The difference between pre- and postoperative PA velocity was not statistically significant.

Conclusions:

PPFs are a safe cost-effective reconstruction modality for distal lower limb defects. This advantage is very valuable in cases of restricted healthcare resources, wars, and during pandemics. In terms of distal limb vascularity, PPFs have no significant impact and can be used safely.

The usefulness of a free thinned deep inferior epigastric artery perforator flap and measurement of the vascular pedicle length: A thin flap with a long pedicle

BACKGROUND

The thinned deep inferior epigastric perforator (DIEP) flap branching from the main trunk to the superolateral direction may be useful because of its long vascular pedicle. DIEP flap is used as an axial-pattern adipose flap. The vascular pedicle length of the thinned DIEP flap was investigated using originally developed software. The clinical application of the thinned DIEP flap was verified in a case series.

METHODS

In 40 patients with enhanced computed tomography (CT) data, the vascular pedicle length of the longest thinned DIEP flap was simulated using the software. A free thinned DIEP flap was used in 10 clinical cases of facial or breast reconstruction.

RESULTS

In all simulated cases, the vascular pedicle of the DIEP branching to the superolateral direction was the longest, and the vascular pedicle could be lengthened up to 34.8% by dissecting the vessels on the fascia as a vascular pedicle. In all the clinical cases, the reconstruction of a complex form defect or reconstruction requiring a long vascular pedicle could be achieved in one stage without any perioperative complications. The intraclass correlation coefficient between simulated pedicle length and dissected pedicle length was 0.99.

CONCLUSION

Thinned DIEP flaps with long vascular pedicles could be elevated safely. Multiple adipose or muscle flaps could be combined without complications. The length of the winding vascular pedicle could be measured using imaging data using the software first developed in the present study. This software would be useful in the planning of a thinned DIEP flap and other free flaps.

Eccentric free muscular perforator flaps in the proximal lateral leg for hand and foot reconstruction

BACKGROUND

We aimed to introduce our modifications by using eccentrically located muscular perforators to shorten the distance between the recipient vessels and the flap pedicle for overcoming the "short pedicle" drawback of the proximal lateral leg perforator (PLLP) flap.

PATIENTS AND METHODS

A retrospective review of 12 cases undergoing free PLLP flap for hand and foot regions reconstruction during 2010 and 2019. The mean age was 43.3 years. Most defects resulted from burn and trauma injuries. The dimensions of defects ranged from 8 × 1.5 cm² to 12 × 6.5 cm² . Muscular perforators were designed eccentrically 1-3 cm away from the central point of the flap to shorten the distance between the recipient vessels and the pedicle. The flap was designed to be 0.5-1 cm larger than the defect.

RESULTS

The flap size ranged from 9 × 2 cm² to 15 × 6 cm² . All pedicles were long enough to ensure an appropriate anastomosis without tension. The post-operative course in all cases was uneventful. All flaps survived without complications. Primary repair of the donor sites was performed in all patients. Donor leg function was not hampered by flap harvesting. All patients were satisfied with the scar after at least 1 year of follow-up.

CONCLUSION

Based on our experience, selection of the eccentric locations of the musculo-cutaneous perforators were effective methods to overcome the short pedicle length of this flap type. Using our modifications, thin PLLP flaps can be used in foot and hand reconstruction with minimal donor site morbidity and a high success rate.

Photoacoustic microscopy: a novel approach for studying perforator skin flap in a mouse model

Background

A comprehensive understanding of cutaneous microvessels is key to the design and use of the perforator skin flap. Compared with the various imaging technologies that have been applied in the clinical practice of the perforator skin flap, photoacoustic microscopy (PAM) is a very promising noninvasive imaging modality with high resolution and deep penetration in biological tissues.

Methods

PAM was employed to explore its multiple applications in a perforator skin flap. The following experiments were then conducted in 3 parts. In part 1, 7 mice were used to obtain the preoperative perforator mapping on the mouse back. In parts 2 and 3, 7 mice were used to design and harvest the multiterritory perforator flap. The status of the flap and the morphological changes of choke vessels were subsequently observed by PAM at several time points.

Results

The results showed that PAM could visualize and assess the vascular physiological and pathological conditions of the skin tissue in real time in vivo with high spatial and temporal resolution. It could also provide preoperative perforator mapping, including the total number of perforators, localization, vascular territories, and diameter. Furthermore, it could offer a quantitative, objective method to monitor the status of the perforator skin flap, and was capable of noninvasive characterization of the changes of choke vessels that play an important role in multiterritory perforator skin flap expansion and survival.

Conclusions

PAM has great potential to be an effective and precise quantitative imaging tool for perforator skin flap research, such in as flap design, monitoring, and choke vessel observation.

One or two venous pedicles by anastomoses for free flaps in reconstruction of the lower extremity: A systematic review and meta-analysis

BACKGROUND

Microsurgical free tissue transfers are a mainstay of lower extremity reconstruction. Despite being a reliable source of soft tissue, complications do arise. Venous congestion is among the most common causes of flap failure in lower extremity reconstruction, an issue that is attributed to venous stasis and impaired venous return in this region. There remains significant debate whether dual venous drainage improves outcomes. The aim of this study was thus to compare one versus two venous anastomoses in lower limb free flap reconstruction.

METHODS

A systematic review of Medline, EMBASE, EBSCO CINAHL, SCOPUS, Proquest Dissertations and Theses Global, Cochrane Library, and PROSPERO from inception to May 20, 2020, was conducted. Two independent reviewers screened titles and extracted data. Our primary outcome was total free flap necrosis. Secondary outcomes were partial flap necrosis, minor complications, flap reoperation, venous thrombosis, and amputation. Methodological quality was assessed using the MINORS criteria and level of evidence.

RESULTS

Three-hundred and fourteen unique titles were identified. All studies were level VI evidence and had a mean MINORS score of 16.1/24. Seven studies (comprising 1499 patients, 910 single venous anastomoses, and 579 double venous anastomoses) met criteria for inclusion. The mean (SD) patient age was 46.5 (7.1) years. Double venous anastomoses did not reduce the rate of minor complications, flap takeback, venous thrombosis, total flap necrosis, or partial flap necrosis when compared to a single vein (all p > .05).

CONCLUSION

In microvascular lower extremity reconstruction, two venous anastomoses did not reduce the rate of minor or major complications.

Novel Classification of the Branching Patterns of the Superficial Branch and the Deep Branch of the Superficial Circumflex Iliac Artery and the Superficial Inferior Epigastric Artery on Computed Tomographic Angiography

BACKGROUND

 Recent advances in the superficial circumflex iliac artery (SCIA) perforator flap transfer emphasized the necessity to comprehensively understand the lower abdominal vasculature. This study aimed to clarify the relationship among the superficial inferior epigastric artery (SIEA), the superficial branch (SCIAs), and the deep branch (SCIAd) of the SCIA.

METHODS

 Computed tomographic angiography was retrospectively reviewed in 312 hemiabdomens in 161 female patients who underwent abdominal flap breast reconstruction. We assessed the presence, caliber, and branching patterns of the SCIA branches and the SIEA.

RESULTS

 The SIEA-SCIA common trunk was present in 40.1% of the hemiabdomen and was identified in either side of the abdomen in 63.6% of patients. At least one superficial vessel larger than 1.5 mm was found in 61.5% of hemiabdomens. Seven branching patterns of the SCIA-SIEA system were noted: (1) the SCIA and the SIEA originated together (17.0%); (2) the SIEA and the SCIAs shared an origin (22.8%), (3) the SCIA and the SIEA branched separately (17.0%), (4) each artery originated separately (8.0%); (5) the SCIAs and the SCIAd emerged together with the SIEA absent (17.3%); (6) the SCIAs and the SCIAd originated separately with the SIEA absent (13.1%); (7) the SIEA and SCIAd originated separately with the SCIAs absent (3.5%).

CONCLUSION

 SCIA-SIEA branching patterns were classified into seven distinctive patterns. This novel classification may help surgeons to choose the optimal pedicle when using the hemi-abdomen region as the donor site.

[Reconstruction of soft tissue defects of the lower extremities]

A reliable reconstruction of soft tissue defects of the lower extremities especially in the distal third of the leg is still a special challenge for reconstructive surgeons. The possibility of salvaging the leg has to be evaluated in the setting of an interdisciplinary team and the timing of the operation(s) with respect to the safety of the patient and a systematic approach with the selection of a suitable flap have to be defined. Traditionally local muscle flaps or free flaps have been established for coverage of defects of the lower extremities. Recently perforator-based flaps have gained popularity for reconstruction of lower extremity defects. Furthermore, new surgical techniques and developments in association with the demographic change have led to a paradigm shift.

Contemporary approach to soft-tissue reconstruction of the lower extremity after trauma

The complex lower extremity wound is frequently encountered by orthopedic and plastic surgeons. Innovations in wound care, soft tissue coverage and surgical fixation techniques allow for improved functional outcomes in this patient population with highly morbid injuries. In this review, the principles of reconstruction of complex lower extremity traumatic wounds are outlined. These principles include appropriate initial evaluation of the patient and mangled extremity, as well as appropriate patient selection for limb salvage. The authors emphasize proper planning for reconstruction, timing of reconstruction and the importance of an understanding of the most appropriate reconstructive option. The role of different reconstructive and wound care modalities is discussed, notably negative pressure wound therapy and dermal substitutes. The role of pedicled flaps and microvascular free-tissue transfer are discussed, as are innovations in understanding of perforator anatomy and perforator flap surgery that have broadened the reconstruction surgeon’s armamentarium. Finally, the importance of a multidisciplinary team is highlighted via the principle of the orthoplastic approach to management of complex lower extremity wounds. Upon completion of this review, the reader should have a thorough understanding of the principles of contemporary lower extremity reconstruction.

[Application of lateral circumflex femoral artery chimeric flap to repair complex wounds of foot and ankle]

OBJECTIVE

To investigate the effectiveness of lateral circumflex femoral artery chimeric flap transplantation in repair of complex wounds of foot and ankle.

METHODS

A retrospective study was conducted to analyze the clinical data of 20 patients with complex wounds of foot and ankle treated with lateral circumflex femoral artery chimeric flap between June 2017 and June 2020. There were 14 males and 6 females with an average age of 42.8 years (range, 21-65 years). Among them, 8 cases had dorsalis pedis tendon defect with or without bone exposure, 4 cases had partial or total Achilles tendon defect without bone exposure, and 8 cases had deep cavity and bone exposure. The wound area ranged from 10 cm×6 cm to 21 cm×11 cm. The time from injury to operation ranged from 6 to 22 days, with an average of 9.4 days. The lateral femoral circumflex artery flap was used in 6 cases with fascia lata flap, 6 cases with rectus femoris aponeurosis flap, and 8 cases with lateral femoral muscle flap. The flap area ranged from 12.0 cm×6.5 cm to 35.0 cm×7.5 cm. All flap donor sites were sutured directly. The survival, appearance, texture, sensation of the flap, and complications of the donor site were observed. The foot and ankle function was evaluated by Kofoed score.

RESULTS

All patients were followed up 8-24 months (mean, 14.2 months). On the 3rd day after operation, 1 case had partial necrosis of 1 flap with fascia lata flap and healed after dressing change; 1 case of chimeric muscle flap developed venous crisis at 12 hours after operation; the chimeric flaps survived successfully in the other 18 patients and the wounds were primary healing. The color and texture of the flaps were good, the flaps recovered protective sensation. Only linear scar remained in the donor site of thigh. There was no sensory disturbance around the incision or walking disturbance. The Kofoed score of the foot and ankle function at last follow-up was 75-96, with an average of 89.8. Among them, 15 cases were excellent, 4 cases were good, and 1 case was qualified. The excellent and good rate was 95.0%.

CONCLUSION

The application of lateral circumflex femoral artery chimeric flap can accurately and stereoscopically repair the complex wounds of foot and ankle and achieve satisfactory effectiveness.

Photoacoustic Microscopy Provides Early Prediction of Tissue Necrosis in Skin Avulsion Injuries

BACKGROUND

Skin avulsion injuries caused by high-energy traffic and machinery accidents are important topics in the field of repair and reconstruction. The injury generates a skin flap with uncertain vascular basis resulting in ischemic necrosis of the distal portion of the flap. Yet there is lack of reliable way for estimating the extent of blood supply in damaged tissue, which has limited the possibility of prompt surgical intervention. Recent studies have confirmed that photoacoustic microscopy imaging has a wide range of applications in the biomedical field owing to its good performance in angiography.

METHODS

In our study, we successfully surgically induced skin avulsion injury on mice hindlimbs. Then, we used this novel approach to image skin microcirculation and predict skin necrosis with impaired blood supply after injury in live mice.

RESULTS AND CONCLUSION

All skin tissues in the avulsed hindlimb flap group show different levels of necrosis at the end of the observation period. The "dark zone" with impaired microcirculation in PAM images, which continuously extends over time, was seen as a prediction of necrosis of skin tissue and at 60 min after surgery was similar to the area of clinical necrosis on postoperative day 7. All these indicate that photoacoustic microscopy imaging is a feasible, precise, high-resolution, non-invasive technique for early prediction of necrosis in skin avulsion injury, providing a promising tool for surgeons to manage the injury.

Reverse Dermis Flap for Coverage of Distal Leg and Ankle Defects

Soft tissue defects of the distal third of the leg and ankle, which frequently expose tendon, bone or osteosynthesis material, are difficult to cover and pose a major challenge to the plastic surgeon. Traditional reconstructive options for this region usually require complex flaps which made them unsuitable for elderly patients or those with multiple comorbidities. We hereby present the reverse dermis flap as an easy and reliable choice to cover this type of wounds and refer our experience in 9 cases in which clinical, operative, and follow-up data were recorded. Of the 9 flaps performed, 8 survived completely and 1 presented a partial flap necrosis, requiring additional surgery. No other operative procedure was required. In conclusion, the reversed dermis flap is a simple, quick, noninvasive, and safe technique for coverage of noble structures such as tendon or bone in the distal third of the leg that every plastic surgeon should incorporate in his surgical armamentary.

A Propeller Perforator Flap in the Distal Lower Extremity: An Alternative to Free Flap Coverage Near the Ankle

As perfusion assessment technologies and microsurgical techniques have evolved, plastic surgeons have become increasingly aggressive and creative in offering reconstructive solutions to limb salvage problems. In the distal lower extremity, pedicled perforator flap transfer has grown in popularity as compared to the historically reliable option of free tissue transfer. Pedicled perforator flaps typically avoid muscle harvest and restore the thin, supple soft tissue in the distal extremity, where there is a relative lack of redundancy of soft tissues. They also allow for a shorter operative time and recovery in otherwise complex wounds of the foot and ankle. This case report highlights the indications, nuance, and post-operative course of a patient who underwent peroneal perforator flap for coverage of a complex ankle wound in the setting of a calcaneal fracture.

Algorithm for covering circumferential wound on limbs with ALTP or/and DIEP flaps based on chain-linked design and combined transplantation

INTRODUCTION

Coverage of circumferential wounds on limbs is a challenging reconstructive job. Here, we propose a skin flap-based algorithm to reconstruct circumferential wound with the chain-linked design and combined transplantation of ALTP and DIEP flap, which could achieve full-coverage and simultaneously primary donor-site closure.

PATIENT AND METHODS

From December 2007 to December 2018, 14 patients with circumferential would on upper or lower limbs underwent reconstruction with ALTP or DIEP flap, by the technique of combined transplantation or chain-linked design, or both. The wound was classified into five different types according to the width compared to the donor site (overall magnitudes and regularity), which was separately reconstructed by five different wound decomposition and corresponding flap design. Flap survivorship, complication on recipient or donor site and any secondary surgeries have been recorded.

RESULTS

14 patients were successfully treated with 22 flaps, including seven patients reconstructed with one flap (4 bi-pedicled, 2 tri-pedicled), 6 patients reconstructed with two flaps (1 in mono-pedicled, 5 in multi-pedicled), one with 3 flaps and skin grafts. Only one donor site was not directly closed, and one experienced dehiscence but finally healed. All flaps survived uneventfully but three had minor edge necrosis and later treated with skin graft.

CONCLUSION

The algorithm is practical in circumferential wound resurfacing on limbs for allowing flexible design, sufficient coverage, and low donor site morbidity.

The Need to Improve Patient-Centered Outcome Reporting Following Lower Extremity Flap Reconstruction: A Systematic Review and Meta-analysis

INTRODUCTION

 Research in lower extremity (LE) wound management involving flap reconstruction has primarily focused on surgeon-driven metrics. There has been a paucity in research that evaluates patient-centered outcomes (PCO). This systematic review and meta-analysis examines articles published between 2012 and 2020 to assess whether reporting of functional and quality of life (QOL) outcomes have increased in frequency and cohesiveness, compared with the previous two decades.

METHODS

 PubMed and Ovid were queried with appropriate Medical Subject Heading (MeSH) terms for studies published between June 2012 and July 2020. For inclusion, each study had to report any outcome of any tissue transfer procedure to the LE in comorbid patients, including complication rates, ambulation rates, flap success rates, and/or QOL measures. The PCO reporting prevalence was compared with a previous systematic review by Economides et al which analyzed papers published between 1990 and June 2012, using a Pearson's Chi-squared test.

RESULTS

 The literature search yielded 40 articles for inclusion. The proportion of studies reporting PCO was greater for literature published between 1990 and 2012 compared with literature published between 2012 and 2020 (86.0 vs. 50.0%, p < 0.001). Functional outcomes were more commonly reported between 1990 and 2012 (78.0 vs. 47.5%, p = 0.003); similarly, ambulatory status was reported more often in the previous review (70.0 vs. 40.0%, p = 0.004). This study solely examined the rate at which PCO were reported in the literature; the individual importance and effect on medical outcomes of each PCO was not evaluated.

CONCLUSION

 Less than 50% of the literature report functional outcomes in comorbid patients undergoing LE flap reconstruction. Surprisingly, PCO reporting has seen a downward trend in the past 8 years relative to the preceding two decades. Standardized inclusion of PCO in research regarding this patient population should be established, especially as health care and governmental priorities shift toward patient-centered care.

Free Tissue Transfer after Open Transmetatarsal Amputation in Diabetic Patients

BACKGROUND

 Transmetatarsal amputation (TMA) preserves functional gait while avoiding the need for prosthesis. However, when primary closure is not possible after amputation, higher level amputation is recommended. We hypothesize that reconstruction of the amputation stump using free tissue transfer when closure is not possible can achieve similar benefits as primarily closed TMAs.

METHODS

 Twenty-eight TMAs with free flap reconstruction were retrospectively reviewed in 27 diabetic patients with a median age of 61.5 years from 2004 to 2018. The primary outcome was limb salvage rate, with additional evaluation of flap survival, ambulatory status, time until ambulation, and further amputation rate. In addition, subgroup analysis was performed based on the microanastomosis type.

RESULTS

 Flap survival was 93% (26 of 28 flaps) and limb salvage rate of 93% (25 of 27 limbs) was achieved. One patient underwent a second free flap reconstruction. In the two failed cases, higher level amputation was required. Thirteen flaps had partial loss or other complications which were salvaged with secondary intension or skin grafts. Median time until ambulation was 14 days following reconstruction (range: 9-20 days). Patients were followed-up for a median of 344 days (range: 142-594 days). Also, 88% of patients reported good ambulatory function, with a median ambulation score of 4 out of 5 at follow-up. There was no significant difference between the subgroups based on the microanastomosis type.

CONCLUSION

 TMA with free flap reconstruction is an effective method for diabetic limb salvage, yielding good functional outcomes and healing results.

Steal syndrome from a superficial circumflex iliac perforator artery flap in a patient with a hypoplastic posterior tibial artery and severe diabetic peripheral artery disease

The use of free flaps in lower extremity reconstructive surgery has seen growing adoption for treating tissue loss in patients with diabetes mellitus and peripheral artery disease as a means for limb preservation. The superficial circumflex iliac perforator artery (SCIP) flap is one of the most commonly utilized flaps in foot reconstruction and has demonstrated benefits over amputation. Patients with impaired vascular and neurologic function are predisposed to complications following lower extremity reconstructive surgery, particularly ischemia in the angiosomes of the arteries used for flap anastomosis. We present the case of a patient who underwent successful SCIP flap reconstruction of the calcaneus but developed gangrene in the forefoot region supplied by a hypoplastic posterior tibial artery in subsequent months. The changes in tissue oxygenation and hemoglobin distribution of the foot are shown using spatial frequency domain imaging throughout the flap healing process and eventual tissue necrosis.

The Superficial Circumflex Iliac Artery Perforator Flap in Lower Extremity Reconstruction

The superficial circumflex iliac artery perforator flap is evolved from the groin flap, which was one of the early free flaps with a good concealed donor site. By further understanding the anatomy of perforators and elevating the flap based on it, this will provide added advantage of being a thin flap, harvesting as a composite flap, and help estimate the limit of skin paddle dimension. Despite these advantages, the relatively short pedicle still remains a challenge where long pedicle flaps are needed. One should select the flaps based on the recipient defect condition along with surgeons' experience, knowledge, and preference.

Free-Style Free Perforator Flaps in Lower Extremity Reconstruction

Improved knowledge of vascular anatomy has enabled surgeons to preoperatively identify perforators and design free-style flaps based on that perforator. Options for choosing the optimal donor site tissues are increased with the free-style technique. This reduces donor site morbidity while providing the same reconstructive success as traditional free skin flaps. The free-style technique allows the surgeon to successfully complete reconstruction when aberrant anatomy is encountered. With the necessary skills in perforator flap dissection and supermicrosurgery, the armamentarium of the reconstructive microsurgeon has been expanded with the introduction of free-style perforator free flaps.

Coverage of cutaneous substance loss in the leg: Techniques and indications

Cutaneous substance loss in the leg is frequent; more often than not, it is trauma-related. It calls for complex management and necessitates the application of all current reconstruction techniques, particularly microsurgery. As regards treatment, the available therapeutic arsenal is highly diversified, ranging from a simple free flap skin graft to local and locoregional flaps. During reconstruction, the surgeon is subjected to several constraints insofar as the objectives of the operation are esthetic as well as functional. Ideally, the fineness of the skin covering the anterior side of the leg will have been scrupulously respected. Reconstruction is aimed at producing a stable and reliable cutaneous envelope while limiting the morbidity of the donor site. The development of free perforator flaps corresponds to these two criteria by producing a fine flap adapted to the cutaneous thickness of the leg and limiting any functional and esthetic sequelae at the donor site.

The esthetic outcome of lower limb reconstruction

BACKGROUND

In recent years, the progress of anatomical knowledge and microsurgical techniques, in particular the development of perforator flaps, has risen the number of flaps available for lower leg reconstruction. The esthetic consequences of flap choice and harvest do have an impact on patients' quality of life. Nowadays, more researchers evaluate the esthetic changes following lower limb reconstruction.

OBJECTIVES

This review aims to summarize the available evidence on the esthetic outcome of lower limb reconstruction.

DATA SOURCES

A systematic review was planned to identify the most relevant indexed articles on this subject. The search was performed on Pubmed database without date of publication limits.

STUDY ELIGIBILITY CRITERIA

All papers about reporting information about the esthetic outcome of lower limb reconstruction were selected. Case reports and the articles not including specific information about complications, secondary procedures, and outcomes were excluded. The articles were categorized according to their topic and date of publication. The full texts of all the articles were obtained and read thoroughly. The references for each article were screened to identify articles that were eventually left outside our database search.

PARTICIPANTS, AND INTERVENTIONS

One hundred and eight articles were retained for the definitive review. Eleven review articles were kept because they represented a good source of information. Thirty-three articles were added after reading the full texts. The articles appear highly heterogeneous and at, this stage, only a critical and qualitative analysis could be performed.

RESULTS

We found information about 7895 lower reconstructions, 1295 local flaps, 6546 free flaps.

LIMITATIONS

The esthetic evaluation is intrinsic subjective. Many psychological and cultural factors influence both the patient and the surgeon. There is not a validated assessment tool for the esthetic outcome of lower leg reconstruction. Therefore, no quantitative analysis was performed.

CONCLUSIONS

Some ancient techniques are today obsolete, like the rectus abdominis free muscle flaps and perhaps free forearm flap, others are always useful, like gracilis and latissimus dorsi free flap. ALT flap is the most versatile perforator flap today available, but the SCIP flap is gaining the favor of a growing number of surgeons. Local flaps will be always performed with success but their indications should not be pushed beyond the medium-size defects. The best cosmetic outcome for each patient cannot necessarily be obtained neither with the easiest techniques nor with the most technically demanding ones. It is necessary to develop validated tools to assess the cosmetic outcome of lower limb reconstruction.

Importance of Vascularity and Selecting the Recipient Vessels of Lower Extremity Reconstruction

BACKGROUND

 Successful lower extremity reconstruction using free flaps begins by identifying a good recipient vessel and understanding the surrounding environment of the defect.

METHODS

 One should consider multiple factors when selecting the recipient vessel such as the status of the axial arteries, trying to preserve flow as much as possible, extent and severity of the defect, and ultimately what type of anastomosis will be ideal.

RESULTS

 Multiple factors of importance are reviewed and show the relevance in decision making and provide an algorithm.

CONCLUSION

 In addition to the multiple factors to be considered, the ultimate decision should be made on the table during surgery when the actual artery or vein is exposed and shows signs of good pulsation and flow.