One-Stage versus Two-Stage Arteriovenous Loop Reconstructions: An Experience on 103 Cases from a Single Center

[Acute and post-acute soft tissue reconstruction]

BACKGROUND

The precise analysis of the injured structures requiring reconstruction in complex wound defects is a prerequisite for successful restoration.

OBJECTIVE

The fundamental reconstructive strategies for soft tissue defects of the extremities including injuries to vessels, nerves and burn wounds in the context of the acute and post-acute trauma phases are presented.

MATERIAL AND METHODS

The different phases of soft tissue reconstruction are described. Recommendations for action with respect to the reconstruction of the functional structures are described. Two clinical case examples illustrate the approach.

RESULTS

The acute reconstruction phase is defined as the period 0-72 h after the traumatic event and includes surgical debridement, primary reconstruction of nerves and vessels using interpositional grafts if necessary and temporary soft tissue reconstruction. Combined thermomechanical trauma requires early debridement combined with internal fixation of open fractures. In the post-acute reconstruction phase, which is generally defined as a period of up to 6 weeks after the traumatic event, definitive soft tissue reconstruction is performed. In the case of long reinnervation distances, nerve transfer or motor replacement plastic surgery is performed in the post-acute phase.

CONCLUSION

The reconstruction of soft tissue after trauma necessitates a stage-dependent approach. In the acute phase procedures aim at the immediate preservation of the limb. In the post-acute phase, definitive soft tissue reconstruction is performed to enable maximum functional preservation. Combined thermomechanical injuries require early surgical treatment in order to prevent infections.

[Modern concepts of interdisciplinary extremity reconstruction in open fractures]

The orthoplastic approach involves the collaboration of orthopedic/trauma surgeons, vascular surgeons and reconstructive microsurgeons. In cases of complex limb fractures, the aims are to optimize blood flow, restore bone stability, reconstruct soft tissue defects, and enhance function and sensitivity. The early administration of antibiotics and a timely, high-quality debridement after initial interdisciplinary assessment are carried out. This is followed by fracture stabilization and temporary wound coverage in order to plan the definitive interdisciplinary procedure. This includes definitive osteosynthesis and soft tissue reconstruction, using local tissue transfer if feasible, or free tissue transfer in cases of extensive trauma zones. The orthoplastic approach allows for faster definitive stabilization, fewer operations, shorter hospital stays, lower complication and revision rates, higher cost-effectiveness and improved long-term function.

Free Flap Reconstruction of Sternal Defects after Cardiac Surgery: An Algorithmic Approach for Dealing with Sparse Recipient Vessels

Background

Sparsity of recipient vessels poses a challenge for microsurgical free flap reconstruction of sternal defects following deep sternal wound infection after cardiac surgery.

Methods

From January 2013, a standardized algorithm for dealing with sparse recipient vessels was strictly followed. In this retrospective study including 75 patients, we compared operative details, surgical complications, and reconstructive outcomes of patients treated according to this algorithm (group A: January 2013-May 2021; n = 46) with a historical control group (group B: January 2000-December 2012, n = 29).

Results

The left internal mammary artery had been harvested for arterial bypass grafting in 40 of 46 cases (87%) in group A and in all cases in group B. The right internal mammary artery (RIMA) and right internal mammary vein (RIMV) were the first choice as recipient vessels. In case of unsuitability of the RIMV, a right cephalic vein (CV) turndown was used for venous outflow. If both RIMA and RIMV proved insufficient, a single-stage arterio-venous loop (AVL) between the CV and subclavian artery (CV-SA AVL), CV and thoracoacromial artery (CV-TA AVL), or subclavian artery and subclavian vein (SA-SV AVL) was established. The algorithmic approach significantly reduced partial flap necrosis [group A: n = 3 (7%) versus group b: n = 7 (24%); P = 0.04], and overall operation time [group A: 360 ± 88 min versus group B: 415 ± 80 min; P = 0.01].

Conclusions

Standardized approaches improve clinical outcomes in microsurgical free flap sternal reconstruction after cardiac surgery.

One vs. two-stage arteriovenous loops in lower extremity reconstruction with free flaps: Systematic review and metanalysis

BACKGROUND

Arteriovenous loops are one of the main therapeutic alternatives to address the absence of recipient vessels in lower extremity microsurgical reconstruction. However, there is no consensus on whether to perform them in one or two surgical stages. The objective of this work is to determine whether the outcome of lower limb free flaps anastomosed to vascular loops depends on the number of surgical stages.

MATERIALS AND METHODS

A literature review was conducted, following PRISMA guidelines, on vascular loops and free flaps in lower limb. Survival rate, as well as major and minor complications were studied. A forest plot and Pearson's chi-square were used for statistical analysis. Study quality was assessed in duplicate using Methodological Index for Non-Randomized Studies (MINORS) and Joanna Briggs Institute (JBI) tool. This study was registered on PROSPERO.

RESULTS

Thirty-two articles using free flaps anastomosed to vascular loops in lower limb, either one or two-stage, were selected. A total of 296 flaps were included, 52% (n = 154) in one and 48% (n = 142) in two surgical times. No statistically significant differences were found in the survival rate (OR = 1.85, 95% CI 0.62; 5.47, p = .09 and p = .344) or major complications (OR = 0.70, 95% CI 0.31; 1.57, p = .56 and p = .92) of flaps between both groups.

CONCLUSIONS

According to the available evidence, the outcome of free flaps anastomosed to vascular loops in the lower limb does not depend on the number of surgical stages they undergo. Although there is some heterogeneity in the groups studied, the decision on the number of procedures to be performed should be determined by the surgeon, concerning the clinical situation of the patient, as well as to the vascular, bone and soft tissue status of the extremity.

[Interdisciplinary defect reconstruction of upper aerodigestive fistulas-case series and treatment algorithm]

BACKGROUND

Persistent complex defects and dysfunctions of the upper aerodigestive tract after tumor surgery represent a major challenge. The aim of this study was to evaluate the effectiveness of an interdisciplinary approach using the free anterolateral thigh flap (ALT) as a reconstruction option in the upper aerodigestive tract.

MATERIALS AND METHODS

The retrospective study identified 5 patients with complex defects after laryngectomy/pharyngolaryngectomy (LE/PLE) and multiple revision surgeries between 2017 and 2023. The operations were performed by an interdisciplinary team from otolaryngology, plastic surgery, and visceral/thoracic surgery. The results of the microsurgical reconstruction were analyzed.

RESULTS

There was an average of six previous operations. The defects included tracheoesophageal fistulas, pharyngocutaneous fistulas, neopharyngeal stenosis, and combinations thereof. Successful reconstruction was achieved in 100% of patients using the ALT flap. In 2 patients, ALT flow-through flaps were used with an additional free jejunal interposition (JI) and in 3 patients split-ALT flaps were used. The major complication rate was 40% and the minor complication rate was 20%.

CONCLUSION

Complex defects of the upper aerodigestive tract with multiple previous operations can be successfully reconstructed. Because of its versatility, the ALT flap seems to be a very good option. Prerequisite for this is an interdisciplinary treatment approach with a critical assessment of patient- and disease-specific factors.

[Revascularization Prior to Defect Reconstruction of the Lower Limb - Essential Cooperation between Plastic and Vascular Surgery]

Treatment of complex ischemic lower leg defects with exposure of deep anatomic structures represents a considerable challenge to involved specialties. In selected patients, limb salvage can be achieved as an alternative to major amputation by means of a combined approach including arterial reconstruction and subsequent free flap transfer. Arterial reconstruction can be performed either by endovascular or open surgical treatment (bypass reconstruction or implantation of an arteriovenous loop) preliminary to defect reconstruction using microsurgical free flap transplantation. Whereas the aim of the arterial reconstruction comprises the establishment of sufficient perfusion and creation of adequate target vessels for the free flap transfer, the selection of the appropriate flap entity depends on the extent of the wound as wells as on the presence of osteomyelitis. Arterial reconstruction and defect reconstruction can be performed as one-stage or two-stage procedure and has become an established and feasible treatment approach in centers. Evaluation of microperfusion by means of indocyanine green can further increase safety and feasibility of this method. Against this background, combined arterial reconstruction and subsequent free flap transfer provides excellent results in terms of amputation free survival and postoperative mobility. Essential is however an individualized decision making in consideration of patient selection and possible contraindications. This approach may be evaluated in mobile patients with complex wounds prior to major amputation.

Reliability of Long Vein Grafts for Reconstruction of Massive Wounds

When handling large wounds, zone of injury is a key concept in reconstructive microsurgery, as it pertains to the selection of recipient vessels. Historically, surgeons have avoided placing microvascular anastomosis within widely traumatized, inflamed, or radiated fields. The harvest of vein grafts facilitates reconstruction in complex cases by extending arterial and/or venous pedicle length. To illustrate the utility and fidelity of these techniques, this paper reviews the indications and outcomes for vein grafting in ten consecutive patients at a single tertiary referral center hospital. The case series presented is unique in three aspects. First, there are two cases of successful coaptation of the flap artery to the side of the arterial limb of an arteriovenous loop. Second, there is a large proportion of cases where vein grafts were used to elongate the venous pedicle. In these 10 cases, the mean vein graft length was 37 cm. We observed zero flap failures and zero amputations. Although limited in sample size, these case data support the efficacy and reliability of long segment vein grafting in complex cases in referral centers.

[The conjoined latissimus dorsi and parascapular free flap for reconstruction of extensive soft tissue defects]

OBJECTIVE

Durable and resilient soft tissue reconstruction of vast defects of the extremities or the torso.

INDICATIONS

Reconstruction of disproportionately large defects, particularly in cases of simultaneous bone and joint reconstruction.

CONTRAINDICATIONS

History of surgery or irradiation of upper back and axilla, impossibility of surgery under lateral positioning; relative contraindications in wheelchair users, hemiplegics, or amputees.

SURGICAL TECHNIQUE

General anesthesia and lateral positioning. First, the parascapular flap is harvested, with the initial skin incision made medially in order to identify the medial triangular space and the circumflex scapular artery. Flap raising then proceeds from caudal to cranial. Second, the latissimus dorsi is harvested, with the lateral border being dissected free first, before the thoracodorsal vessels are visualized on its undersurface. Flap raising then proceeds from caudal to cranial. Third, the parascapular flap is advanced through the medial triangular space. If the circumflex scapular and thoracodorsal vessels originate separately from the subscapular axis, an in-flap anastomosis is warranted. Subsequent microvascular anastomoses should be performed outside the zone of injury, typically in an end-to-end fashion of the vein and end-to-side fashion of the artery.

POSTOPERATIVE MANAGEMENT

Postoperative anticoagulation with low-molecular-weight heparin under anti-Xa monitoring (semitherapeutic in normal-risk and therapeutic in high-risk cases). Hourly clinical assessment of flap perfusion for 5 consecutive days, followed by stepwise relaxation of immobilization and commencement of dangling procedures in cases of lower extremity reconstruction.

RESULTS

Between 2013 and 2018, 74 conjoined latissimus dorsi and parascapular flaps were transplanted to cover vast defects of the lower (n = 66) and upper extremity (n = 8). The mean defect size was 723 ± 482 cm² and the mean flap size was 635 ± 203 cm². Eight flaps required in-flap anastomoses for separate vascular origins. There was no case of total flap loss.

Scalp Reconstruction Using the Latissimus Dorsi Free Flap: A 12-Year Experience

BACKGROUND

Complex scalp defects are regularly reconstructed using microvascular tissue transfer. The latissimus dorsi free flap is one of the workhorse flaps used in scalp reconstruction. These cases necessitate, particularly in the elderly, a close cooperation between plastic surgeons and neurosurgeons. The purpose of this study was to evaluate the suitability of the latissimus dorsi free flap for complex scalp reconstructions and to analyze potential risk factors.

METHODS

A retrospective study identified 43 patients undergoing complex scalp reconstruction using a latissimus dorsi free flap at our department between 2010 and 2022.

RESULTS

The mean patient age was 61 ± 18 years. Defects were mostly caused by oncologic tumor resections (n = 23; 55%), exposure to a cranioplasty (n = 10; 23%) or infection (n = 4; 9%). The most frequent recipient vessels were the superficial temporal artery (n = 28; 65%), external carotid artery (n = 12; 28%) and the venae comitantes (n = 28; 65%), external jugular vein (n = 6; 14%). The reconstructive success rate was 97.7%. There was one total flap loss (2%). Partial flap loss occurred in five cases (12%). Follow-up was 8 ± 12 months. Major complications were seen in 13 cases, resulting in a revision rate of 26%. Multivariate logistic regression identified active tobacco use as the only risk factor for major complications (odds ratio 8.9; p = 0.04).

CONCLUSION

Reconstruction of complex scalp defects using the latissimus dorsi free flap yielded high success rates. Among the potential risk factors, active tobacco use seems to affect the outcome of complex scalp reconstructions.

Acellular Human Placenta Small-Diameter Vessels as a Favorable Source of Super-Microsurgical Vascular Replacements: A Proof of Concept

In this study, we aimed to evaluate the human placenta as a source of blood vessels that can be harvested for vascular graft fabrication in the submillimeter range. Our approach included graft modification to prevent thrombotic events. Submillimeter arterial grafts harvested from the human placenta were decellularized and chemically crosslinked to heparin. Graft performance was evaluated using a microsurgical arteriovenous loop (AVL) model in Lewis rats. Specimens were evaluated through hematoxylin-eosin and CD31 staining of histological sections to analyze host cell immigration and vascular remodeling. Graft patency was determined 3 weeks after implantation using a vascular patency test, histology, and micro-computed tomography. A total of 14 human placenta submillimeter vessel grafts were successfully decellularized and implanted into AVLs in rats. An appropriate inner diameter to graft length ratio of 0.81 ± 0.16 mm to 7.72 ± 3.20 mm was achieved in all animals. Grafts were left in situ for a mean of 24 ± 4 days. Decellularized human placental grafts had an overall patency rate of 71% and elicited no apparent immunological responses. Histological staining revealed host cell immigration into the graft and re-endothelialization of the vessel luminal surface. This study demonstrates that decellularized vascular grafts from the human placenta have the potential to serve as super-microsurgical vascular replacements.

Microsurgical Strategies after Free Flap Failure in Soft Tissue Reconstruction of the Lower Extremity: A 17-Year Single-Center Experience

Background: There is no clear consensus on the optimal surgical strategy for providing safe coverage in salvage free flap surgery after total free flap failure. Methods: A retrospective study was conducted to evaluate patients with total failure of the primary free flap in lower extremity reconstruction between 2000 and 2017. Results: In a cohort of 1.016 patients, we identified 43 cases of total flap failure (4.2%). A total of 30 patients received a salvage free flap with a success rate of 83.3% (25/30). One patient received a secondary salvage free flap. Overall limb salvage after primary free flap loss was 83.7% (36/43). Conclusions: Microsurgical management of free flap loss in the lower extremity is challenging and requires a decisive re-evaluation of risk factors and alternative strategies. This should include reconsidering the flap choice with a tendency towards traditional and safe workhorse flaps, a low-threshold switch to different recipient vessels, including arteriovenous (AV) loops, bypasses (especially in case of venous insufficiency) and back-up procedures, such as negative pressure wound therapy or dermal regeneration templates with skin grafting in cases of lower demand and critically ill patients. We derived one suggestion from our previous practice: replacing perforator flaps with axial pattern flaps (“safe workhorses”).

Soft tissue reconstruction of complex infra-inguinal wounds following revisionary vascular surgery

INTRODUCTION

Large, full thickness infra-inguinal wounds following revision revascularization procedures of the lower extremity are a challenging complication for reconstructive surgery. Frequently, these patients present with various comorbidities and after several previous reconstructive attempts and therefore no straightforward soft tissue reconstruction is likely.

METHODS

Patients who presented with large, complex inguinal wounds for soft tissue reconstruction were analyzed retrospectively in terms of flap choice, outcome and complication rates. A focus was set on the reconstructive technique and a subgroup analysis was assessed.

RESULTS

19 patients (11 men, 8 women) who received 19 flaps (17 pedicled, two free flaps) were included in this retrospective study. Average patient age was 73.3 years (range: 53-88 years). 10 fascio-cutaneous flaps (ALT, 52.6%) and 9 muscle flaps (47.4%) were applied. Among muscle flaps, 3 pedicled gracilis flaps, 4 pedicled rectus abdominis flaps and two free latissimus dorsi flaps were used. No flap losses were observed except one case of limited distal flap necrosis (gracilis group). Body Mass Index (BMI) ranged from 19 to 37, mean 26.8. Mean surgery time in all patients was 165.9 minutes (range: 105-373 minutes). Revision surgery due to local wound healing problems averaged 1.6 in all patients. In all cases sufficient soft tissue reconstruction was achieved and bypasses were preserved. Lengths of stay averaged 27.2 (14 to 59 days). Mortality was considerably (10.5%) due to systemic complications (One patient died due to a heart attack 4 weeks postoperatively, another patient died due to an extensive pulmonary embolism two weeks postoperatively).

CONCLUSION

Soft tissue reconstruction of complex inguinal wounds after revision vascular surgery is challenging and wound-healing problems are expectable. In addition to the rectus abdominis flap the pedicled ALT flap is feasible in a broad variety of medium to large wounds. Free flap reconstruction is recommended for very large defects. A structured interdisciplinary approach is required for the management of complex wounds after vascular surgery to prevent and to deal with complications and perioperative morbidity.

The Free Myocutaneous Tensor Fasciae Latae Flap—A Workhorse Flap for Sternal Defect Reconstruction: A Single-Center Experience

Introduction: Deep sternal wound infections (DSWI) after cardiac surgery pose a significant challenge in reconstructive surgery. In this context, free flaps represent well-established options. The objective of this study was to investigate the clinical outcome after free myocutaneous tensor fasciae latae (TFL) flap reconstruction of sternal defects, with a special focus on surgical complications and donor-site morbidity. Methods: A retrospective chart review focused on patient demographics, operative details, and postoperative complications. Follow-up reexaminations included assessments of the range of motion and muscle strength at the donor-site. Patients completed the Quality of Life 36-item Short Form Health Survey (SF-36) as well as the Lower Extremity Functional Scale (LEFS) questionnaire and evaluated aesthetic and functional outcomes on a 6-point Likert scale. The Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scales (POSAS) were used to rate scar appearance. Results: A total of 46 patients (mean age: 67 ± 11 years) underwent sternal defect reconstruction with free TFL flaps between January 2010 and March 2021. The mean defect size was 194 ± 43 cm2. The mean operation time was 387 ± 120 min with a flap ischemia time of 63 ± 16 min. Acute microvascular complications due to flap pedicle thromboses occurred in three patients (7%). All flaps could be salvaged without complete flap loss. Partial flap loss of the distal TFL portion was observed in three patients (7%). All three patients required additional reconstruction with pedicled or local flaps. Upon follow-up, the range of motion (hip joint extension/flexion (p = 0.73), abduction/adduction (p = 0.29), and internal/external rotation (p = 0.07)) and muscle strength at the donor-sites did not differ from the contralateral sides (p = 0.25). Patient assessments of aesthetic and functional outcomes, as well as the median SF-36 (physical component summary (44, range of 33 to 57)) and LEFS (54, range if 35 to 65), showed good results with respect to patient comorbidities. The median VSS (3, range of 2 to 7) and POSAS (24, range of 18 to 34) showed satisfactory scar quality and scar appearance. Conclusion: The free TFL flap is a reliable, effective, and, therefore, valuable option for the reconstruction of extensive sternal defects in critically ill patients suffering from DSWIs. In addition, the TFL flap shows satisfactory functional and aesthetic results at the donor-site.

Vein Grafts in Free Flap Reconstruction: Review of Indications and Institutional Pearls

SUMMARY

Vein grafts enable soft-tissue reconstruction in cases of insufficient pedicle length, a lack of nearby recipient vessels, and a wide zone of injury caused by trauma or radiation therapy. The purpose of this article is to provide a comprehensive review of vein grafts in free flap reconstruction focusing on the timing of arteriovenous loops, complications, and surgical technique. Vein graft indications, types of vein grafts, and location-specific considerations are also reviewed. Three reconstructive microsurgeons at high-volume centers were asked to offer institutional pearls on the order of anastomosis, selection of donor veins, and timing of arteriovenous loops. In terms of gap length, vessel gaps less than 10 cm may be reconstructed with an interposition or transposition vein graft. For longer gaps, surgeons should consider the use of arteriovenous loops, transposition arteriovenous loops, or flow-through flaps. Both one and two-stage arteriovenous loops are used, depending on patient comorbidities, potential exposure of critical structures, and surgeon preference. Although one-stage arteriovenous loops expedite the reconstructive process, two-stage arteriovenous loops require shorter operations and help identify patients at risk of flap failure. Although whether the use of vein grafts increases flap failure rates is controversial, complications are highest in lower extremity reconstruction, cases of a prolonged interval between stages in two-stage arteriovenous loops, and unplanned vein grafts.

Combined versus Single Perforator Propeller Flaps for Reconstruction of Large Soft Tissue Defects: A Retrospective Clinical Study

Sufficient wound closure of large soft tissue defects remains a challenge for reconstructive surgeons. We aimed to investigate whether combined perforator propeller flaps (PPFs) are suitable to expand reconstructive options. Patients undergoing PPF reconstruction surgery between 2008 and 2021 were screened and evaluated retrospectively. Of 86 identified patients, 69 patients received one perforator propeller flap, while 17 patients underwent combined PPF reconstruction with multiple flaps. We chose major complications as our primary outcome and defined those as complications that required additional surgery. Postoperatively, 27 patients (31.4%) suffered major complications. The propeller flap size, the type of intervention as well as the operation time were not associated with a higher risk of major complications. A defect size larger than 100 cm², however, was identified as a significant risk factor for major complications among single PPFs but not among combined PPFs (OR: 2.82, 95% CI: 1.01−8.36; p = 0.05 vs. OR: 0.30, 95% CI: 0.02−3.37; p = 0.32). In conclusion, combined PPFs proved to be a reliable technique and should be preferred over single PPFs in the reconstruction of large soft tissue defects at the trunk and proximal lower extremity.

Revisionary soft tissue reconstruction of posterior midline defects after spinal surgery-plastic reconstructive options including perforator flaps

Background

Chronic prevertebral soft tissue defects with exposed metal hardware following spinal surgery represent a challenging complication. Frequently patients underwent multiple previous operations due to wound complications. Surrounding soft tissues are often compromised due to malperfusion, severe subcutaneous scarring, previous local advancement flaps and therefore impair stable wound closure.

Methods

Patients after spinal surgery who received complex soft tissue reconstructions between 2011 and 2015 were analyzed retrospectively. Patient`s age, risk factors, wound size, cause and defect location as well as complication rates were evaluated. A focus was set on therapeutic strategies and decision-making concerning reconstructive techniques.

Results

Fourteen patients receiving 27 pedicled and one free flap were included in the study. Patients mean age was 51.1 years, mean wound size was 144 cm². Defects were located in the lumbar spine [8], cervical spine [2] and thoracic spine [1], respectively. Three patients suffered from extensive defects affecting more than one area. Mean time of flap surgery was 213 minutes. Fifteen perforator-based flaps and 11 non-perforator (classic rotation-flaps), 1 pedicled and 1 free latissimus dorsi flap were used. In 9 patients (64.3%) different flaps had to be combined in a single-staged procedure due to large wounds. Implant material was removed completely in six patients (42.9%), whereas in five patients (35.7%) implants were replaced within the operation for soft tissue reconstruction. In three patients (21.4%) initial implant removal or replacement was not possible which leads to prolonged postoperative wound infections.

Conclusions

Most patients with exposed spinal hardware suffered from multiple comorbidities and showed a poor general condition. Due to the reduced soft tissue quality wound healing is significantly impaired. Exposed implant material should be replaced or removed when possible. Therefore, the complete armamentarium of plastic reconstructive techniques is required for wound closure. Today, perforator flaps play a prominent role due to the variability, excellent vascularization and sufficient subcutaneous filling capacities.

Implementation and Validation of Free Flaps in Acute and Reconstructive Burn Care

Microsurgical free flap reconstruction in acute burn care offers the option of reconstructing even challenging defects in a single stage procedure. Due to altered rheological and hemodynamic conditions in severely burned patients, it bears the risk of a higher complication rate compared to microsurgical reconstruction in other patients. To avoid failure, appropriate indications for free flap reconstruction should be reviewed thoroughly. Several aspects concerning timing of the procedure, individual flap choice, selection and preparation of the recipient vessels, and perioperative measures must be considered. Respecting these specific conditions, a low complication rate, comparable to those seen in microsurgical reconstruction of other traumatic limb defects, can be observed. Hence, the free flap procedure in acute burn care is a relatively safe and reliable tool in the armamentarium of acute burn surgery. In reconstructive burn care, microsurgical tissue transfer is routinely used to treat scar contractures. Due to the more robust perioperative condition of patients, even lower rates of complication are seen in microsurgical reconstruction.

Multistep reconstruction of a post-traumatic defect in the lower limb with AV loop and free myocutaneous latissimus dorsi flap combined with a perforator monitor skin island after loss of ALT flap

Crush injuries of the lower extremity with extensive osseous and soft tissue damage impose a big challenge even for an interdisciplinary reconstructive approach. Multistep reconstruction with negative wound pressure therapy for soft tissue management and external fixation for osseous stability preceding free flap transfer leads to optimized outcome. We report the successful multistep reconstruction of a third-degree open right tibial fracture with extensive soft tissue defect with an arteriovenous loop preceding latissimus dorsi flap coverage with a perforator skin island after loss of an anterior lateral thigh (ALT) flap due to intima damage of the recipient vessels. The described method is a safe reconstructive concept after primary flap loss with persistent extensive tissue damage.

Role, Management, and Outcome of Free Flap Reconstruction for Acute Full-Thickness Burns in Hands

INTRODUCTION

Severe thermal trauma to the hand can result in major impairment and reduced function due to defective healing or even extremity loss. Full-thickness injuries frequently incur exposure of tendons or bone and require an early and stable coverage with soft tissue transplants to allow for rapid induction of exercise and to preserve structures and hand function. Free tissue transfer to the hand after thermal trauma is a rare indication, and safety, management, and outcome of free flap surgery for severe acute burn injuries to the hand remains underreported.

METHODS

Patients with primary reconstructions of full-thickness burn injuries to the hand undergoing microsurgical free tissue transfer surgery were retrospectively assessed in a period from 2013 to 2016. Salvage strategy of the extremity, postoperative complications, length of hospital stay, and primary reconstructive result were quantified and analyzed. Functional outcome measures (range of motion and grip strength) were assessed during clinical follow-up examinations.

RESULTS

During the investigated period, 13 patients were identified undergoing reconstruction of 14 hands via free flap transplantation after severe burn injury in the acute phase. Nine anteriolateral thigh flaps (64%), 3 latissimus dorsi flaps (18%), 1 serratus anterior flap, and 1 tensor fasciae lata flap (7%) were performed. In all cases, salvage of the affected extremity was achieved, although 1 flap (7%) was lost during the early postoperative period requiring secondary reconstruction via pedicled groin flap. Further complications were venous thrombosis (n = 2; 14%) and hematoma (n = 2; 14%). Mean length of hospital stay was 51 days. Functional outcome during follow-up examination after an average of 9.3 months was inhomogeneous depending on the pattern of injury and ranged from complete recovery to nearly entire loss of hand function.

CONCLUSIONS

Free flap transfer can be a mandatory and valuable tool to cover full-thickness burn injuries of the hand early in the clinical course of thermal trauma and may provide extremity salvage by favorable means of reconstruction to achieve acceptable functional outcomes, in the most severe cases. Although microsurgical failure rates in burn patients are slightly higher than in free flap transfer to the upper extremity in general, it can be performed with reasonable risk-to-benefit ratio.

Vein Grafting in Microsurgical Lower Extremity Reconstruction: Outcome Analysis of Primary versus Secondary Salvage Procedures

BACKGROUND

 Many microsurgeons fear high complication rates and free flap loss when vein grafting is necessary to restore blood flow at the recipient site. The aims of this study were to comparatively analyze surgical outcomes of interposition vein grafts (VG) in microsurgical primary lower extremity reconstruction and secondary salvage procedures.

METHODS

 A retrospective study was conducted on 58 patients undergoing free flap transfers with vein grafting for primary lower extremity reconstruction (cohort 1) and secondary salvage procedures (cohort 2) between 2002 and 2016. A matched-pair analysis of both cohorts and 58 non-VG flaps was performed. Patient data, preoperative conditions, flap and vein graft characteristics, postoperative outcomes such as flap failure, thrombosis, and wound complications were analyzed.

RESULTS

 A total of 726 free flap transfers were performed. In total, 36 primary reconstructions (5%) utilized 41 interposition VG (cohort 1). Postoperative vascular compromise was observed in 65 free flaps (9%). In total, 22 out of 65 secondary salvage procedures (33.8%) utilized 26 interposition VG (cohort 2). Two total flap losses occurred in each cohort (5.6 vs. 9.1%; p = 0.63). Postoperative complications were observed in 38.9% of free flaps in cohort 1 and 72.7% in cohort 2 (p = 0.01). Takeback for microvascular compromise was comparable in both cohorts (19.4 vs. 22.7%; p = 0.75). Microvascular complications occurred more often in cohort 2 (22.7%) than in cohort 1 (8.3%; p = 0.28). Lower extremity salvage rates were high among both cohorts (94.4 vs. 90.9%; p = 0.63). Matched-pair analysis did not show any relevant differences on takebacks and flap loss (p = 0.32 and p = 1.0).

CONCLUSION

 In complex lower extremity reconstructions, VG can be performed with acceptable complication rates and outcomes in primary and especially in salvage cases. With careful planning and a consistent surgical protocol, VG can provide reliable success rates in limb salvage.

Perforator-Based Flaps for Defect Reconstruction of the Posterior Trunk

INTRODUCTION

Full-thickness soft tissue defects of the back remain challenging clinical problems for reconstructive surgeons. Among a vast variety of local flap options, perforator-based local flaps gain increasing popularity lately. Because mostly heterogeneous patient cohort comparison of different perforator flaps is difficult and decision-making algorithms are lacking.

METHODS

Patients, who received a local perforator-based soft tissue reconstruction between 2012 and 2019, were evaluated retrospectively. Patients' data were evaluated in terms of flap type and dimension, wound size and cause, surgery time, postoperative complications, and hospitalization. A focus was set on decision making concerning reconstructive techniques and flap choice for defect closure.

RESULTS

Thirty-six patients (17 women, 19 men) were included, who received 40 perforator-based local flaps to reconstruct extended defects of the posterior trunk. Mean patient age was 56.3 years and mean hospitalization was 29 days. Average time of flap surgery was 179.7 minutes. Mean flap size was 160.8 cm and average defect size was 110 cm. Defects occurred because of tumor resection (50%), orthopedic/trauma surgery (16.7%), or pressure sores (33.3%). Twenty-eight propeller flaps (PPFs, 70%) and 12 perforator-based VY-advancement flaps (P-VYF, 30%) were transferred. In 4 patients, a bilateral approach using more than one flap was necessary. Revision surgery was required in 9 patients (25%) because of postoperative hematoma (n = 3), postoperative wound infection (n = 3), partial flap necrosis (1× P-VYF) and 2 flap losses (2× PPFs).

CONCLUSIONS

Pedicled perforator flaps are a reliable option for soft tissue reconstruction of complex wounds of the posterior trunk. A flexible surgical strategy is mandatory, and the individual perforator anatomy has to be considered. In most cases, P-VYFs or PPFs are reliably possible and allow sufficient defect reconstruction. However, skin incisions should always be performed in a way that classic random pattern flaps are still possible. Even in large defects combined, local perforator flaps may lead to sustainable soft tissue reconstructions without functional donor site deficits.

A multivariable miRNA signature delineates the systemic hemodynamic impact of arteriovenous shunt placement in a pilot study

Arteriovenous (AV) fistulas for hemodialysis can lead to cardiac volume loading and increased serum brain natriuretic peptide (BNP) levels. Whether short-term AV loop placement in patients undergoing microsurgery has an impact on cardiac biomarkers and circulating microRNAs (miRNAs), potentially indicating an increased hemodynamic risk, remains elusive. Fifteen patients underwent AV loop placement with delayed free flap anastomosis for microsurgical reconstructions of lower extremity soft-tissue defects. N-terminal pro-BNP (NT-proBNP), copeptin (CT-proAVP), and miRNA expression profiles were determined in the peripheral blood before and after AV loop placement. MiRNA expression in the blood was correlated with miRNA expression from AV loop vascular tissue. Serum NT-proBNP and copeptin levels exceeded the upper reference limit after AV loop placement, with an especially strong NT-proBNP increase in patients with preexistent cardiac diseases. A miRNA signature of 4 up-regulated (miR-3198, miR-3127-5p, miR-1305, miR-1288-3p) and 2 down-regulated miRNAs (miR30a-5p, miR-145-5p) which are related to cardiovascular physiology, showed a significant systemic deregulation in blood and venous tissue after AV loop placement. AV loop placement causes serum elevations of NT-proBNP, copeptin as well as specific circulating miRNAs, indicating a potentially increased hemodynamic risk for patients with cardiovascular comorbidities, if free flap anastomosis is delayed.

Efficacy of the Arteriovenous Loop for Free Flap Reconstruction in Patients with Complex Limb Trauma: Case Series and Literature Review

Background and objectives: Complex limb traumas are commonly treated with microsurgical reconstruction and free flaps. However, complications are frequent in patients affected by a previous trauma or comorbidity, atheromasia and a single valid vessel. Free flap reconstruction is indeed a challenging procedure in complex injuries, which may increase the risk of limb ischemia. The Arteriovenous loop (AVL) technique may be considered an efficient alternative treatment. We herein report our procedure and previous research regarding the AVL method using a two-step reconstruction in cases of complex high-energy limb injuries. Materials and Methods: In this single center retrospective cohort study, all the patients from 2014 to 2018 who underwent to AVL reconstruction were assessed. A total of six patients were included in the study for traumatic limb trauma. The two-stage technique was performed each time. The age and sex of patient, the time between stage one and two, the length of AVL loop and rate of free flap success were evaluated. Results: A total of seven AVL reconstructions were performed. The mean age of patients was 36 years old. Eight free flaps were performed; six free flaps were transferred to the vascular loops. The average time between stage one and two was 13 days. The mean length of the pedicle was 25 cm for the upper limb and 33.7 cm for the lower limb. All the free flaps successfully take root. In one case, a surgical revision was required the second day post-operatory due to venous congestion. Conclusions: AVL is a useful and safe technique in microsurgical reconstruction which will prevent vascular complications. Our investigations suggest the efficacy and feasibility of a two-step intervention in acute post-traumatic events. A single-step procedure should be preferred in chronic situation and oncologic reconstruction.

A Structured, Microsurgical Training Curriculum Improves the Outcome in Lower Extremity Reconstruction Free Flap Residency Training: The Ludwigshafen Concept

BACKGROUND

 Risk stratification, economic pressure, and a flat learning curve make the realization and development of proper microsurgical skills and competences a challenging task in the daily clinical practice. In previous studies, we were able to show that microsurgical procedures, e.g., free flaps and replantations, are safe training procedures and teachable in daily clinical practice in view of certain issues of risk stratification. The present study aims to evaluate further improvements in terms of safety and complication rates for free flaps as a training procedure after introduction and continuous implementation of a structured in-house training curriculum for microsurgical skills and competences and a 24-hour free accessible microsurgical training facility for the plastic surgery resident.

METHODS

 This retrospective comparative cohort study was conducted to review whether microsurgical skills for free flaps to the lower extremity can further be improved after implementation of the curriculum and a 24-hour accessible training facility. Therefore, we compared cohort A before (2009-2012) and B after (2014-2017) implementation. Patient demographics, procedural characteristics, and outcome parameters for free tissue transfer of the lower extremity were evaluated.

RESULTS

 The comparison of both cohorts showed a significantly reduced postoperative complication rate for cohort B (p <0.05). Furthermore, operation time was shorter, and the hospital stay could be significantly decreased (p <0.01). Workhorse flaps for plastic surgical training were the anterior lateral thigh (ALT) flap or the musculus latissimus dorsi (LD) flap. However, even more complex procedures with arteriovenous loops could be safely performed by plastic surgery residents under the supervision of the senior surgeon in exceptional cases.

CONCLUSION

 The implementation of a regularly held, microsurgical in-house training curriculum with 24-hour accessible training facility improves procedural and outcome parameters for free flaps to the lower extremity for surgical residents and is an elementary part of skills and competency training. However, risk stratification, repeated surgical exposure, expertise, and institutional infrastructures are essential and must be taken into consideration.

Combined (endo-)vascular intervention and microsurgical lower extremity free flap reconstruction-A propensity score matching analysis in 5386 ACS-NSQIP patients

BACKGROUND

Compromised lower limb perfusion due to vascular changes such as peripheral artery disease impedes wound healing and may lead to large-scale tissue defects and lower limb amputation. In such patients with defects and compromised or lacking recipient vessels, combined vascular reconstruction with free flap transfer is an option for lower extremity salvage.

METHODS

By using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database (2005-2018), we analyzed two patient cohorts undergoing (A) free flap lower limb reconstruction (LXTR) only and (B) combined (endo-)vascular reconstruction (vascLXTR). The preoperative variables assessed included demographic data and comorbidities, including smoking, diabetes mellitus, preoperative steroid use, and American Society of Anesthesiology (ASA) Physical Status Classification. Using a neighbor matching algorithm, we performed a 1:1 propensity score matching of 615 LXTR patients and 615 vascLXTR patients. Bivariate analysis for postoperative surgical and medical complications was performed for outcomes in the propensity-matched cohort.

RESULTS

We identified 5386 patients who underwent microsurgical free flap reconstruction of the lower extremity. A total of 632 patients underwent a combined (endo-)vascular intervention and lower extremity free flap reconstruction. Diabetes and smoking were more prevalent in this group, with 206 patients having diabetes (32.6%) and 311 being smokers (49.2%). More patients returned to the operating room in the cohort that underwent a combined vascular intervention (24.4% versus 9.9%; p<0.0001). The 30-day mortality for patients undergoing a combined vascular procedure was 3.5%, compared with 1.3% with free tissue transfer only (p<0.0001).

CONCLUSION

Despite the risks associated, the combined intervention decreases the very high mortality associated with limb amputation in severely sick patient populations. Careful preoperative assessment of modifiable risk factors may reduce complication rates while allowing limb salvage.

Arteriovenous Loops Enable Free Tissue Transfer With Otherwise Inadequate Local Donor and Recipient Vessels

BACKGROUND/AIM

Free flap reconstruction with damaged or diseased vessels is a challenging problem. We describe our case series using an arteriovenous loop or bypass surgery with free flaps for complex defect reconstructions at the lower extremity and the pelvic region.

PATIENTS AND METHODS

In this single-center retrospective cohort study 11 consecutive patients (mean age=73 years, range=53-88 years) were operated on, between June 2016 and August 2018. Patients were reconstructed with free gracilis flaps (n=8), free latissimus dorsi flap (n=1) and chimeric scapular flap (n=1), respectively.

RESULTS

The mean loop length was 30 cm (range=12-40 cm). The loop/bypass revision rate was 27% (3/11), and the overall flap loss rate was 20% (2/10). After a mean follow-up time of 17 months (range=12-24 months), the limb salvage rate was 75% (6/8).

CONCLUSION

We successfully reconstructed complex defects with poor recipient vessels using arteriovenous loops or bypass surgery and free flaps.

[Reconstruction of lower limbs in old age-an interdisciplinary approach : Strategies for trauma surgery, vascular surgery and plastic surgery]

The treatment of complex injuries of the lower extremities in geriatric and/or multimorbid patients requires optimized preoperative and perioperative management as well as differentiated and interdisciplinary surgical approaches. Timely and definitive treatment should be strived for to avoid longer periods of immobilization. Temporary external stabilization of complex fractures, when necessary, should be followed by permanent loading stable internal osteosynthesis as soon as possible. Accompanying soft tissue defects are reconstructed after wound débridement using the full armamentarium of plastic and reconstructive surgical procedures, including microvascular free flap. In the context of perfusion compromised soft tissue situations, negative pressure wound therapy can provide sterile temporary defect coverage and aid in preconditioning poorly vascularized tissue before definitive reconstruction. A clarification of the vascular status in geriatric patients is paramount and relevant perfusion disorders should be treated either by intervention or open surgery before complex reconstructive interventions. Close interdisciplinary coordination of the various surgical procedures is imperative in order to guarantee an optimized stable reconstructive outcome with acceptable patient risk. Taking these principles into account, the reconstruction of complex trauma to the extremities can be carried out even in geriatric or multimorbid patients in specialized interdisciplinary surgical centers with excellent functional results.

Wound closure by means of free flap and arteriovenous loop: Development of flap autonomy in the long-term follow-up

Free flaps in combination with arterial reconstruction by means of arteriovenous loops or bypass have, meanwhile, been established as a therapeutic option in defect reconstruction for areas without recipient vessels. Our aim was to analyse the long‐term performance, flap autonomy, and the flap perfusion. Patients receiving this combined reconstruction at a single‐centre institution were included. During follow‐up examination, the patency of arterial reconstruction was investigated by duplex ultrasound. Flap micro‐circulation was assessed by laser Doppler flowmetry and white light tissue spectrometry (O2C) as well as by indocyanine green fluorescence angiography. Twenty‐three patients could be clinically followed up. Duplex ultrasound showed, in four cases, arterial pedicle occlusion in spite of vital flap. Comparison of the O2C perfusion parameters between flaps with occluded pedicles and those with intact inflow showed no significant difference (parameters sO2: P = .82; Flow: P = .31). Similar results were obtained by fluorescence angiography; no significant difference could be detected between both groups (parameters Ingress P = .13; Ingressrate P = .54). Combined vascular reconstruction with free tissue transfer is associated with a good long‐term outcome and wound closure. Even after flap transplantation to areas with critical tissue perfusion, the flap can develop autonomy and thus survive after pedicle occlusion.

AV loop free flap: an interdisciplinary approach for perineal and sacral defect reconstruction after radical oncological exenteration and radiation in a colorectal cancer patient

Background

The free flap transfer of a latissimus dorsi flap (LDF) for the closure of sacral wound defects after pelvic exenteration and radiation therapy offers a successful tool of the plastic surgeon. This case report shows the successful coverage using an upstream arterio-venous (AV) loop in combination with an LDF.

Case presentation

We describe the case of a patient who underwent a pelvic exenteration and radiation therapy due to a local recurrence of rectal cancer. The initially used VRAM flap could not ensure a satisfactorily wound closure. An interdisciplinary approach first yielded an AV loop using both greater saphenous veins and was connected to the arteria and vena femoris followed by a free LDF transfer, which was performed 11 days later. The result was an excellent reconstructive and plastic coverage of the sacral wound defect with a well-perfused LDF. The long-term result showed a perfectly integrated flap in the sacral region.

Conclusion

We recommend the free LDF for the coverage of large wound defects in irradiated areas after the failure of VRAM flap. If an AV loop is necessary within the flap transfer, we recommend conducting two procedures to guarantee the perfusion of the AV loop.