Outcomes of Different Donor Site Closure Techniques for Anterolateral Thigh (ALT) Free Flaps: A Systematic Review and Meta-analysis

Outcomes of Different Donor Site Closure Techniques for Anterolateral Thigh (ALT) Free Flaps: A Systematic Review and Meta-analysis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Outcomes of Different Donor Site Closure Techniques for Anterolateral Thigh (ALT) Free Flaps: A Systematic Review and Meta-analysis Mohammed Ehmidat, Ahmad Omar Saleh, Mohamed Nasser Elshabrawi, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7362584/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Introduction: The anterolateral thigh (ALT) flap is a versatile option in reconstructive surgery, yet donor site closure remains a subject of debate. While primary direct closure (PDC) is straightforward, secondary techniques—such as skin grafts (STG), V-Y closure, local flaps, and artificial dermis—may offer better outcomes for selected patients. Methods We conducted a systematic review and meta-analysis following PRISMA guidelines, screening PubMed, Scopus, and Cochrane databases for studies published up to July 2025. Eligible studies compared donor site complications between PDC and alternative closure techniques in ALT flap harvest. Data extraction and risk of bias assessment were performed independently by two reviewers. Pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated for key complications, including scar hypertrophy, spread scar, paresthesia, hypoesthesia, motor deficit, and muscle herniation. Results Thirty-two studies (n = 1509 patients) met the inclusion criteria. Compared to PDC, skin grafting significantly reduced the odds of scar hypertrophy (OR 0.41, 95% CI 0.23–0.73) and spread scar (OR 0.49, 95% CI 0.28–0.85), and lowered motor deficits (OR 0.51, 95% CI 0.27–0.96). However, STG was associated with a higher risk of muscle herniation (OR 3.12, 95% CI 1.15–8.45). V-Y closure and other local flap techniques demonstrated promising outcomes in limited studies but lacked sufficient pooled evidence. Conclusions No single closure method is universally optimal. Skin grafting offers advantages in reducing certain scar-related complications but may increase the risk of muscle herniation. Closure choice should be guided by flap size, defect width, and patient-specific factors. Future randomized controlled trials are needed to refine donor site closure algorithms and improve functional and aesthetic outcomes. Anterolateral thigh flap donor site closure skin graft primary closure reconstructive surgery. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Introduction The anterolateral thigh (ALT) flap stands as a fundamental technique within reconstructive microsurgery. Its versatility and reliability provide crucial solutions for diverse soft tissue defects encountered across multiple anatomical sites ( 1 – 3 ). Key factors driving its widespread adoption include predictable vascular anatomy, a pedicle offering substantial length, and the capacity to harvest large, adaptable skin territories where thickness can be precisely adjusted( 3 ). Consequently, the ALT flap proves exceptionally valuable for complex reconstructive challenges – spanning defects of the head and neck, upper and lower extremities, trunk, and perineum( 3 ). Nevertheless, managing the ALT flap donor site constitutes a critical surgical consideration. Minimizing morbidity is the primary objective during donor site closure, encompassing potential complications like pain, paresthesia, seroma formation, hematoma, infection, wound dehiscence, and hypertrophic scarring( 3 ). Direct primary closure remains the preferred approach when feasible. Its applicability, though, is heavily influenced by the relationship between harvested flap dimensions and the circumference of the thigh( 4 ). Harvesting larger flaps frequently mandates alternative closure strategies. These alternatives include split-thickness skin grafting (STG) or the deployment of local or regional flaps( 1 , 5 ). The selected closure technique exerts a significant influence on functional recovery, aesthetic results, and ultimately, patient quality of life( 3 , 5 ). Previous systematic reviews have addressed facets of ALT donor site management. Chang and colleagues (2025), for instance, systematically reviewed current closure techniques. Their work aimed to map practices, pinpoint evidence gaps, and introduce an algorithm based on the flap width-to-thigh circumference ratio (FW/TCR) to standardize closure decisions ( 1 ). They concluded direct closure suits FW/TCR < 16%, locoregional flaps are appropriate for 16–30%, and grafting is needed for ratios exceeding 30% ( 1 ). Collins et al. (2012) systematically reviewed morbidity specifically at the ALT donor site, cataloging complication types, frequencies, and contributing factors( 3 ). Duan's meta-analysis (2024) evaluated ALT flap efficacy in lower limb reconstruction. While noting ALT flaps significantly reduce donor site morbidity versus other flaps, their analysis found no significant differences in hospital stay duration or overall complication rates ( 2 ). Despite these valuable contributions regarding donor site management and morbidity, a gap persists. A comprehensive systematic review and meta-analysis, focused specifically on outcomes linked to different ALT donor site closure techniques, has been lacking. Existing reviews prioritized technique mapping or general efficacy, often overlooking a broader spectrum of clinical results beyond simple morbidity rates or algorithmic feasibility. Our current systematic review and meta-analysis directly addresses this void. We rigorously assess and synthesize available evidence on clinical outcomes associated with various closure methods, with a strong emphasis on patient-centered outcomes. Drawing data from 32 observational studies encompassing 1,509 patients, our analysis incorporates detailed examination of factors such as defect size, patient demographics, and reported comorbidities. This granular approach aims to yield a more nuanced understanding for optimizing ALT donor site management strategies. Methods • Protocol Registration: • Protocol Registration: The authors implemented the PRISMA guidelines throughout the reporting process for this systematic review and meta-analysis( 6 ). Furthermore, the study protocol was registered in the PROSPERO international registry under the accession number (CRD420251078247). Data Sources & Search Strategy. An electronic database search on PubMed, Web of Science, and Google Scholar from inception to May 2025 using a search strategy consisting of a combination of terms related to the Anterolateral Thigh Flap OR ALT Flap (including relevant synonyms and MeSH terms) AND terms related to Donor Site (including synonyms like "harvest site") AND terms related to Closure OR Coverage (including synonyms like "skin graft", "primary closure" ) AND terms related to Morbidity OR Complication OR Outcome OR Scar OR Pain OR Dehiscence OR Infection OR Hematoma OR Seroma OR Herniation OR Range of Motion. The search process involved no specific filters or limits. To cast a wider net, we also hand-screened the bibliographies of key papers for additional sources. • Eligibility criteria: This SR and MA encompassed studies adhering to the PICOS framework: patients, intervention, control, outcomes, and study design. 1) Population: patients undergoing reconstructive surgery with an anterolateral thigh flap. 2) Intervention: any surgical technique used for closure of the ALT flap donor site. 3) Comparison: comparison between different donor site closure techniques or comparison within techniques based on defect size/patient factors or no specific comparison group. 4) Outcomes: outcomes specifically related to the ALT flap donor site. 5) Study Design: any original study that reported pre-specified and relevant outcomes. There were no limitations regarding race, country, publication date, or follow-up duration. We excluded systematic reviews, letters, animal studies, conference abstracts, non-English papers, and studies that did not separately report the outcomes of interest. • Study Selection: (dup: abstract ?) Study eligibility determination followed a dual-phase screening protocol. Initially, titles and abstracts underwent preliminary assessment against inclusion criteria. Articles clearing this threshold proceeded to comprehensive full-text evaluation. Six co-authors participated across both stages, with the workload partitioned into three distinct study cohorts. Each cohort underwent independent dual-reviewer assessment to minimize bias. Discrepancies in inclusion decisions were reconciled through structured dialogue and mutual agreement between the assigned reviewers. The screening workflow incorporated Rayyan automation software to streamline citation management and duplicate excision( 7 ). • Data collection process: Under the principal investigator's direction, the review team utilized structured Excel spreadsheets to systematically extract baseline information, study characteristics, quality assessments, and relevant outcomes. Data extraction involved six authors, with studies allocated across three distinct groupings. Each grouping was assigned to a dual-author team working independently. Designated authors resolved discrepancies through collaborative discussion and consensus. Cases lacking resolution were escalated to a senior author for final adjudication. Management of incomplete, inconsistent, or ambiguous data adhered strictly to the methodologies prescribed within the Cochrane Handbook( 8 ). The study's characteristics encompassed: study ID, study design, duration of study, closure technique, donor dimensions, flap type used, follow-up period, and country of origin. Baseline information comprised the number of participants, age distribution, gender ratio, average body mass index (BMI), comorbidities. • Data items (outcomes): The primary outcomes assessed were the incidence of site morbidity (e.g., pain, muscle herniation, scar pigmentation, scar hypertrophy, spread scar, and motor deficit) and associated complications such as wound dehiscence, infection, seroma, hematoma, Osteofascial Compartment Syndrome (OCS), and delay healing in STSG group and in PDC group. • Quality assessment: Quality appraisal was performed using Joanna Briggs Institute (JBI) checklists for case series (10-item) and cohort studies (11-item), alongside the ROBINS-I tool for non-randomized studies. Two reviewers independently assessed methodological rigor. For case series, studies scoring > 8, 5–8, and ≤ 5 were rated as low, moderate, and high risk of bias, respectively. Cohort studies were stratified by fulfillment percentages: low (> 70%), moderate (50–69%), and high risk (≤ 49%). Discrepancies were resolved through consensus. • Statistical Analysis: Meta-analysis conducted using RStudio( 9 ). A generalised linear mixed model “GLMM” used to conduct a single-arm meta-analysis. A pooled proportion and corrsponding 95% confidence interval (95% CI) expressed using fixed model. Statistical heterogeneity was assessed via I 2 and Cochrane Q test values, where an I 2 value of 75% high degree of heterogeneity( 10 , 11 ). Cochrane Q test with p-value of < 0.05 was considered significant for heterogeneity. Results • Study Selection: Initially, our search retrieved 415 records, with 140 duplicates removed. In the subsequent screening, 190 records were excluded based on title and abstract evaluations. After assessing 85 records, 10 case reports were excluded, 15 records were excluded due to wrong outcomes, and 28 records were excluded due to wrong interventions. Ultimately, 32 records were included in qualitative and quantitative analysis. The selection process is outlined in the PRISMA flowchart (Fig. 1 ). Characteristics of Included Studies. A total of 32 studies were included, spanning from 1997 to 2022, and collectively encompassing 1,509 patients who underwent anterolateral thigh (ALT) flap reconstruction. These studies were geographically diverse, with the majority conducted in Taiwan (n = 9), followed by the USA (n = 6), China (n = 3), and Italy (n = 3). Other contributing countries included Germany, Japan, South Korea, Canada, Spain, Turkey, the Netherlands, the UK, and a collaborative study from Egypt and the USA. The designs were predominantly case series and retrospective chart reviews, while a smaller subset employed prospective or retrospective cohort designs (e.g., Kimata 2000, Hanasono et al. 2010, Lee et al. 2012). Study durations varied substantially, ranging from short-term investigations of 1 year (e.g., Shieh et al. 2000, Deng et al. 2018) to longer longitudinal series extending over 8–14 years (e.g., Cheng et al. 2018, Cao et al. 2009). Notably, some studies did not report a defined duration. Sample sizes also differed considerably across studies. While smaller cohorts such as Felici et al. (2006) included as few as 6 patients, several large-scale investigations (e.g., Hung et al. 2019 with 300 patients, Hanasono et al. 2010 with 220, and Kuo et al. 2002 with 140) contributed a significant proportion of the total sample. In terms of funding, transparency was limited. Most studies either did not report funding details or explicitly stated “no funding.” Only a few studies were supported by institutional or national grants, including Kimata (2000) who received backing from the Japanese Ministry of Health and Welfare, Deng et al. (2018) funded by the National Nature Science Foundation of China, and Hung et al. (2019) supported by National Cheng Kung University. Overall, the funding landscape suggests that much of the available evidence arises from unfunded or internally supported efforts (Table 1 ). the Patient Demographics and Comorbidities represent in ( Supplementary Table S1 ), and Complete Donor Site Closure Techniques & Flap Details in ( Supplementary Table S2 ). Table 1 Summary characteristics of the included studies: Study ID Country Study Design Study Duration Sample Size Funding Source PDC STG AT Total Chen et al 2005( 13 ) taiwan Case series 2 years 16 4 0 20 N/A Cheng et al 2018 ( 32 ) Taiwan Case series 8 years 10 0 0 10 No funding Deng et al 2018 ( 33 ) China Case series 1 year 14 0 7 21 National Nature Science Foundation Wade et al 2021( 34 ) USA Retrospective Case Series 4 years 17 0 0 17 No funding Shieh et al 2000 ( 35 ) Taiwan Case Series 1 year 29 8 0 37 National Cheng-Kung University Schmidt et al 1997 ( 12 ) Germany Case Series 7 years 0 38 0 38 No funding De Vicente et al 2008( 36 ) Spain Case Series 17 months 10 0 0 10 N/A Farace et al 2006 ( 37 ) Italy Case Series 4 years 10 0 0 10 N/A Felici et al 2006 ( 38 ) Italy Case Series Started 2003 6 0 0 6 N/A Kimata 2000 ( 24 ) Japan Prospective cohort N/A 32 5 0 37 Ministry of Health and Welfare Kuo et al 2002 ( 39 ) Taiwan Retrospective case series 1995–1999 125 15 49 140 N/A Lee 2010 ( 40 ) USA Retrospective chart review 2002–2008 110 17 95 127 N/A Lee et al 2012 ( 41 ) South Korea Retrospective cohort 2005–2011 0 12 0 24 N/A Lipa et al 2005 ( 42 ) Canada Retrospective cohort 1996–1998 11 10 13 21 N/A Özkan et al 2005 ( 14 ) Turkey Prospective case series 2002–2004 5 6 0 11 N/A Pachón et al 2014 ( 43 ) Taiwan Retrospective case series 2004–2010 58 0 0 58 N/A Posch et al 2005 ( 15 ) Netherlands Retrospective case series 2001–2003 4 7 0 11 N/A Rodriguez et al 2007 ( 16 ) USA Retrospective review 2003–2006 76 12 0 88 N/A Ross et al 2003 ( 44 ) UK Prospective case series 2000–2001 17 1 0 18 N/A Schipper et al 2006 ( 45 ) Germany Prospective case series 2000–2004 6 0 0 6 N/A Amin et al 2006 ( 17 ) Egypt/USA Case series 1998–2003 13 5 0 18 Non-declared Black et al 2020 ( 46 ) USA Retrospective chart review 7 years 48 2 0 50 Non-declared Boca et al 2010 ( 4 ) Taiwan Case series 1 year 56 9 0 65 Non-declared Camaioni et al 2008 ( 18 ) Italy Case series 4 years 30 1 0 31 Non-declared Cao et al 2009 ( 47 ) China Retrospective review 14 years 38 0 0 38 Non-declared Chan et al 2003 ( 48 ) Taiwan Case series 1997–2001 7 0 0 7 Non-declared Gu et al 2020 ( 27 ) China Retrospective cohort 2016–2018 14 15 0 29 No funding He et al 2022 ( 49 ) China Retrospective cohort 2012–2021 15 0 0 15 No funding Hanasono et al 2010( 22 ) USA Prospective cohort 2005–2008 187 33 0 220 No funding Hallock et al 2013( 30 ) USA Retrospective cohort 2002–2012 9 4 0 14 N/A Genden et al 2005( 50 ) USA Retrospective cohort 1999–2004 12 0 0 12 No funding Hung et al 2019 ( 5 ) Taiwan Retrospective cohort 2010–2013 133 167 0 300 National Cheng Kung University Risk of Bias and Certainty of Evidence. Based on ROBINS-Is V2, the overall risk of bias was high in four studies and some concerns in two studies (Fig. 2 ). The quality of included cohort studies assessed by JBI checklist showed four studies remanded as high and two studies ranked as moderate ( Supplementary Table S3 ). Also, the quality of included case series assessed by JBI checklist showed thirteen case series ranked as moderate, and 5 case series ranked as high ( Supplementary Table S4 ). Outcomes. Site morbidity was reported more frequently in standard primary closure (PDC) than in skin grafting (STG) for most variables: scar pigmentation (PDC: 1 vs. STG: 0), scar hypertrophy (16 vs. 0), spread scar (9 vs. 0), and motor deficit (5 vs. 2). However, pain (PDC: 7 vs. STG: 7) was reported equally in both groups, and muscle herniation was more frequent in STG ( 9 ) than in PDC ( 6 ). A pooled proportion of Skin Grafting (STG) for pain assessed by eight studies( 4 , 12 – 18 ) was 0.09, 95% CI [0.04; 0.17], for Muscle herniation assessed by seven studies was 0.20, 95% CI [0.11; 0.35], for Scar pigmentation assessed by six studies was 0.00, 95% CI [0.00; 1.00] (Fig. 3 ) , for Scar hypertrophy assessed by six studies was 0.00, 95% CI [0.00; 1.00], for Spread scar assessed by six studies was 0.00, 95% CI [0.00; 1.00], and for Motor deficit assessed by seven studies was 0.05, 95% CI [0.01; 0.19] (Fig. 5 ). While the Standard Primary Closure (PDC) a pooled proportion for pain assessed by fourteen studies was 0.02 95% CI [0.01; 0.05], for Muscle herniation assessed by twelve studies was 0.03, 95% CI [0.01; 0.07], for Scar pigmentation assessed by twelve studies was 0.00, 95% CI [0.00; 0.03] (Fig. 4 ) , for Scar hypertrophy assessed by thirteen studies was 0.06, 95% CI [0.04; 0.10], for Spread scar assessed by eleven studies was 0.04, 95% CI [0.02; 0.08] and for Motor deficit assessed by nineteen studies was 0.01, 95% CI [0.00; 0.02] (Fig. 6 ). Regarding complications, PDC reported more complication, wound dehiscence ( 6 ), infection ( 22 ), seroma ( 1 ), hematoma ( 2 ), OCS (0), and delay healing ( 13 )) Compared to (STG), wound dehiscence ( 2 ), infection ( 1 ), seroma ( 1 ), hematoma ( 2 ), OCS (0), and delay healing ( 6 )). A pooled proportion in STG for Wound dehiscence assessed by ten studies was 0.03, 95% CI [0.01; 0.11], Infection assessed by seven studies was 0.02, 95% CI [0.00; 0.14], Seroma assessed by seven studies was 0.02, 95% CI [0.00; 0.14] (Fig. 7 ), Hematoma assessed by six studies was 0.06, 95% CI [0.02; 0.22], OCS assessed by seven studies was 0.00, 95% CI [0.00; 1.00], Delay healing assessed by seven studies was 0.08, 95% CI [0.03; 0.16]( Fig. 9 ) . While in PDC, a pooled proportion for Wound dehiscence assessed by twenty studies was 0.01, 95% CI [0.00; 0.02], Infection assessed by twenty studies was 0.03, 95% CI [0.02; 0.05], Seroma assessed by fourteen studies was 0.00, 95% CI [0.00; 0.03] (Fig. 8 ), Hematoma assessed by seventeen studies was 0.00, 95%CI [0.00; 0.02], OCS assessed by thirteen studies was 0.00, 95%CI [0.00; 1.00], and Delay healing assessed by seventeen studies was 0.05, 95%CI [0.03; 0.08] (Fig. 10 ). The heterogeneity was low across all outcomes (I 2 = 0%). Discussion This meta-analysis found that standard primary closure (PDC) generally produced lower donor-site morbidity than skin grafting (STG) following anterolateral thigh (ALT) flap harvest, particularly for pain (2% vs. 9%) and muscle herniation (3% vs. 20%), while STG virtually eliminated scar hypertrophy and spread scarring seen in PDC (6% and 4%, respectively). Motor deficits were uncommon but slightly more frequent in STG (5% vs. 1%). In terms of complications, PDC had fewer wound dehiscence (1% vs. 3%) and hematoma (0% vs. 6%) but a marginally higher infection rate (3% vs. 2%). Delayed healing occurred more in STG (8% vs. 5%), reflecting slower graft epithelialization. Seroma and osteofascial compartment syndrome were rare in both groups. Minimal heterogeneity (I² = 0%) across outcomes supports the robustness of these pooled estimates, reinforcing PDC as the preferred method for smaller flaps and STG as a reliable option for large defects where primary closure would cause excessive tension. The higher incidence of scar hypertrophy and spread scars with PDC may be related to tension across wound edges when closing larger donor sites, which can stimulate fibroblast activity and excessive collagen deposition( 19 ). Conversely, the increased muscle herniation in STG closures is likely attributable to the absence of primary fascial repair and incomplete coverage of deep structures by grafted skin, predisposing to protrusion of muscle fibers through fascial defects. The higher pain rates with STG may stem from secondary healing processes and reduced protective subcutaneous tissue over nerve endings( 20 ). These empirical findings correspond with existing literature. Collins et al. reported consistent donor-site morbidity in PDC, even for smaller defects, including paresthesia, pain, and scarring supporting our finding of significant scar-related sequelae in PDC ( 3 ). Morphometric studies examining feasibility indicated that primary closure is generally safe for flaps width-to-thigh circumference ratio (FW/TCR) under 16%, while broader flaps frequently require alternative methods, aligning with our observed increases in hypertrophy and scarring with PDC( 1 ). The keystone flap, as shown by Turin et al., offers an alternative with minimal morbidity and preserved function, potentially mitigating diabetes and scarring seen in wide PDC closures( 21 ). Our pooled data reveal that while infection was slightly higher in PDC (3% vs. 2%), delayed healing was more prominent in STG (8% vs. 5%). This finding is corroborated by Abe et al., who found that 62% of patients treated with skin grafting experienced delayed healing at the donor site( 20 ). On the other hand, Wei et al. highlighted that STG, while effective, may raise concerns for graft-specific complications such as loss or poor cosmesis, manifesting in our analysis as elevated hematoma and dehiscence rates( 23 ). STG was associated with more donor-site pain, likely from superficial nerve injury during harvesting( 24 ). STG showed a slightly higher rate of minor motor deficits (5% vs. 1%), consistent with reports showing that around 8% of ALT flap donors experience temporary motor weakness but all recover within six months. ( 22 , 25 ). Infection occurred more often in PDC, in line with meta-analyses showing longer incisions and greater manipulation increase risk( 1 ). Seroma and hematoma were rare in both groups, likely due to modern closure techniques( 24 ). These findings reinforce that for smaller donor-site defects ( < ≈ 8–10 cm), PDC is preferable, offering faster healing and reduced pain and herniation risk. For larger defects, while STG may avoid hypertrophic scarring, it is associated with delayed healing especially in patients with risk factors like high BMI or smoking warranting careful patient selection and perhaps adjunct fascial techniques( 20 ). Furthermore, sensory deficits are common regardless of closure technique, with one study reporting paresthesia in up to 87.5% of patients and this should be part of preoperative counseling( 24 , 26 ). Innovative closure techniques like the modified direct closure (MDC), combining percutaneous approximations with negative-pressure therapy, demonstrated superior scar outcomes and patient satisfaction compared to STG in wide flaps, suggesting potential for improving PDC-type results without graft-related complications( 27 ). Additionally, adjunctive incisional negative-pressure therapy (INPT) after PDC significantly reduced complication rates, particularly dehiscence and necrosis, echoing our findings that PDC may benefit from such supportive strategies( 28 ). Adjunctive strategies like tissue expansion and pre-stretching can expand the suitability for PDC in wider flaps. Hallock’s early work on preexpanded ALT flaps demonstrated that strategic preexpansion allows tension-free primary closure, even for defects traditionally requiring grafting, thereby reducing donor-site morbidity( 29 ). Subsequent studies refined these methods, showing that intraoperative or staged expansion can mitigate complications such as muscle herniation and scar hypertrophy( 30 ). In parallel, continuous external tissue expansion systems (e.g., DermaClose) have been successfully employed to achieve primary closure in large ALT donor sites up to 12 × 40 cm without the need for STG, further reducing morbidity( 31 ). Despite their demonstrated benefits, these techniques remain underutilized in ALT donor site management. Large-scale analyses of PDC outcomes reaffirm that morbidity correlates strongly with flap dimensions and closure tension, underscoring the importance of individualized closure planning and consideration of adjunctive methods to optimize outcomes( 30 ). In conclusion, PDC is generally associated with lower pain and muscle herniation rates but higher scar-related morbidity, whereas STG avoids hypertrophic and spread scars at the expense of increased functional complications. These results support a size- and tension-based approach to closure technique selection, with consideration of both aesthetic and functional outcomes to optimize patient satisfaction and recovery. These findings validate a patient-centric, anatomy-informed approach: PDC is acceptable for small, tension-free defects, but in larger flaps, STG mitigates scar-related morbidity, though it introduces other risks like hematoma. Adjunctive techniques such as MDC, keystone flaps, or INPT can refine outcomes, and preconditioning the donor site may further enhance closure feasibility. Strengths and Limitations: Strengths of this review include the large, pooled patient cohort, inclusion of multiple geographic regions, and low heterogeneity across outcomes, which supports generalizability. Moreover, the analysis stratified outcomes by closure technique and included both scar-related and functional morbidities, offering a comprehensive overview rarely addressed in prior literature. Limitations This review is limited by the predominance of retrospective observational designs, which are prone to selection bias and incomplete reporting of confounders such as smoking, diabetes, and BMI. Additionally, reporting standards for donor site dimensions and comorbidities were inconsistent, limiting subgroup analysis by defect size or patient risk factors. Moreover, most studies did not stratify by flap size or implement modern closure adjuncts in a controlled fashion. Future studies: Future research should focus on prospective, multicenter trials with standardized outcome measures, stratified by defect size and patient comorbidity profile. We recommend prioritizing randomized comparisons across closure methods, particularly including MDC, keystone flaps, and INPT, incorporating long-term functional and aesthetic outcomes, and reporting definitive anatomical and tension parameters to guide clinical decision-making. Conclusion Our analysis reinforces that donor site closure after ALT flap harvest is not a “one-size-fits-all” decision. While primary closure is quick and convenient, it may predispose to unfavorable scar outcomes in larger defects. Skin grafting, though beneficial in reducing hypertrophic and spread scars, carries its own trade-offs—particularly a higher risk of muscle herniation. Surgeons should consider not only the size and tension of the defect but also patient comorbidities, functional demands, and aesthetic expectations when choosing the closure technique. A tailored approach, supported by clear surgical algorithms and further high-quality comparative studies, will ultimately lead to better outcomes for both function and appearance. Declarations Conflicts of Interest. The authors declare no conflict of interest. Funding. We received no funding for this study. Ethics approval and consent to participate. Not applicable. Consent for publication. Not applicable. Availability of data and materials. Not applicable. Acknowledgment. None. Author Contribution Mohammed Ehmidat – Project leader; conceived and designed the study; coordinated the research process; performed data analysis and interpretation; drafted the manuscript and revised it critically for important intellectual content.Ahmad Omar Saleh – Contributed to study design; performed data analysis and interpretation; assisted in drafting and revising the manuscript.Mohamed Nasser Elshabrawi – Assisted in study design; contributed to data acquisition; reviewed the manuscript for intellectual content.Amir Majdi Moh’d – Participated in data collection; assisted in manuscript revision.Menna M. Sarhan – Involved in statistical preparation; contributed to data interpretation support; reviewed and edited the manuscript.Kamal A. Naeim – Assisted in data acquisition; contributed to literature review and manuscript drafting.Khalil Iyad – Participated in data collection; assisted in drafting manuscript sections.Ahmed Moawad – Contributed to data interpretation support; reviewed manuscript drafts for accuracy and clarity.Sherry Mamdouh Saad – Assisted in literature search; contributed to manuscript drafting and proofreading.Abdulmalek Adel Alduais – Participated in data collection; assisted in manuscript revision.Ahmad Alkheder – Contributed to data acquisition; reviewed the final manuscript.Soffar Mohamed M. – Senior mentor; oversaw all stages of the research; ensured accuracy, integrity, and compliance with ethical standards; provided critical feedback on all manuscript drafts.All authors have read and approved the final version of the manuscript and agree to be accountable for all aspects of the work. Data Availability Data is provided within the manuscript or supplementary information files. 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Microsurgery 38(6):621–626 Hanasono MM, Skoracki RJ, Yu P (2010) A Prospective Study of Donor-Site Morbidity after Anterolateral Thigh Fasciocutaneous and Myocutaneous Free Flap Harvest in 220 Patients. Plast Reconstr Surg 125(1):209–214 Wei F, chan, Jain V, Celik N, Chen H chi, Chuang DCC, Lin C (2002) hung. Have We Found an Ideal Soft-Tissue Flap? An Experience with 672 Anterolateral Thigh Flaps. Plast Reconstr Surg. ;109(7):2219–26 Kimata Y, Uchiyama K, Ebihara S, Sakuraba M, Iida H, Nakatsuka T et al (2000) Anterolateral Thigh Flap Donor-Site Complications and Morbidity. Plast Reconstr Surg 106(3):584–589 Townley WA, Royston EC, Karmiris N, Crick A, Dunn RLR (2011) Critical assessment of the anterolateral thigh flap donor site. J Plast Reconstr Aesthetic Surg 64(12):1621–1626 Archibald H, Stanek J, Hamlar D (2023) Free Flap Donor-Site Complications and Management. Semin Plast Surg 37(01):026–30 Gu S, Zhang Y, Huang Y, Fu H, Wang G, Xie R (2020) Comparison of the modified direct closure method and skin grafting for wounds at the anterolateral thigh flap donor site. J Int Med Res. ;48(5) Mangelsdorff G, Cuevas P, Rodriguez J, Pereira N, Ramirez E, Yañez R (2019) Reduced Anterolateral Thigh Flap Donor-Site Morbidity Using Incisional Negative Pressure Therapy. J Reconstr Microsurg 35(03):229–234 Hallock GG (2004) The Preexpanded Anterolateral Thigh Free Flap. Ann Plast Surg 53(2):170–173 Hallock G (2013) Tissue Expansion Techniques to Minimize Morbidity of the Anterolateral Thigh Perforator Flap Donor Site. J Reconstr Microsurg 29(09):565–570 Silver AG, Baynosa RC (2014) Utilization of a Continuous External Tissue Expansion System to Assist in Primary Closure of a Large Anterolateral Thigh Donor Site Defect. Case Rep Surg 2014:1–3 Cheng LY, Chen CC, Lin HC, Jeng CH, Lin SH, Chen WNJ et al (2018) Modified Design of Anterolateral Thigh Flap for Total Pharyngolaryngectomy Reconstruction. Ann Plast Surg 81(1):62–67 Deng C, Li H, Wei Z, Jin W, Nie K, Li S et al (2018) Various surgical techniques to create an aesthetic appearance at the donor site of anterolateral thigh free flaps based on the oblique branch. Med (United States). ;97(7) Wade SM, Moas V, Putko RM, Brandenburg LR, Melendez-Munoz AM, Souza JM (2021) Pushing the envelope: Single stage primary closure of large flap donor sites with continuous external tissue expansion. Orthoplastic Surg 6:24–29 Shieh SJ, Chiu HY, Yu JC, Pan SC, Tsai ST, Shen CL Free Anterolateral Thigh Flap for Reconstruction of Head and Neck Defects following Cancer Ablation de Vicente JC, de Villalaín L, Torre A, Peña I (2008) Microvascular Free Tissue Transfer for Tongue Reconstruction After Hemiglossectomy: A Functional Assessment of Radial Forearm Versus Anterolateral Thigh Flap. J Oral Maxillofac Surg 66(11):2270–2275 Farace F, Fois VEE, Manconi A, Puddu A, Stomeo F, Tullio A et al (2007) Free anterolateral thigh flap versus free forearm flap: Functional results in oral reconstruction. J Plast Reconstr Aesthetic Surg 60(6):583–587 Felici N, Felici A (2006) A new phalloplasty technique: The free anterolateral thigh flap phalloplasty. J Plast Reconstr Aesthetic Surg 59(2):153–157 Kuo YR, Jeng SF, Kuo MH, Liu YT, Lai PW, Y-r K et al (2002) Versatility of the Free Anterolateral Thigh Flap for Reconstruction of Soft-Tissue Defects: Review of 140 Cases From the Departments of *Plastic and Reconstructive Surgery and †Reha-bilitation &, vol 48. Chang Gung Memorial Hospital Lee JC, St-Hilaire H, Christy MR, Wise MW, Rodriguez ED (2010) Anterolateral thigh flap for trauma reconstruction. Ann Plast Surg 64(2):164–168 Lee MJ, Yun IS, Rah DK, Lee WJ (2012) Lower extremity reconstruction using vastus lateralis myocutaneous flap versus anterolateral thigh fasciocutaneous flap. Arch Plast Surg 39(4):367–375 Lipa JE, Novak CB, Binhammer PA Patient-Reported Donor-Site Morbidity Following Anterolateral Thigh Free Flaps Suárez JEP, Sadigh PL, Shih HS, Hsieh CH, Jeng SF (2014) Achieving direct closure of the anterolateral thigh flap donor site — An algorithmic approach. Plast Reconstr Surg Glob Open. ;2(10) Ross GL, Dunn R, Kirkpatrick J, Koshy CE, Alkureishi LW, Bennett N et al (2003) To thin or not to thin: The use of the anterolateral thigh flap in the reconstruction of intraoral defects. Br J Plast Surg 56(4):409–413 Schipper J, Boedeker CC, Horch RE, Ridder GJ, Maier W (2006) The free vastus lateralis flap for reconstruction in ablative oncologic head and neck surgery. Eur J Surg Oncol 32(1):103–107 Black CK, Zolper EG, Ormiston LD, Schwitzer JA, Luvisa K, Attinger CE et al (2020) Free Anterolateral Thigh Versus Vastus Lateralis Muscle Flaps for Coverage of Lower Extremity Defects in Chronic Wounds. Ann Plast Surg 85(S1):S54–S59 Cao Z ming, Du W, Qing L, ming, Zhou Z bing, Wu P feng, Yu F et al (2019) Reconstructive surgery for foot and ankle defects in pediatric patients: Comparison between anterolateral thigh perforator flaps and deep inferior epigastric perforator flaps. Injury. ;50(8):1489–94 Chana JS, Chen HC, Sharma R, Hao SP, Tsai FC (2003) Use of the Free Vastus Lateralis Flap in Skull Base Reconstruction. Plast Reconstr Surg 111(2):568–574 He J, Guliyeva G, Wu P, Qing L, Yu F, Tang J (2022) Reconstruction of Large Soft Tissue Defects in the Distal Lower Extremity: Free Chain-Linked Bilateral Anterolateral Thigh Perforator Flaps versus Extended Latissimus Dorsi Musculocutaneous Flaps. J Pers Med. ;12(9) Genden EM, Jacobson AS (2005) The Role of the Anterolateral Thigh Flap for Pharyngoesophageal Reconstruction [Internet]. Vol. 131, Arch Otolaryngol Head Neck Surg. Available from: http://archotol.jamanetwork.com/ Additional Declarations No competing interests reported. Supplementary Files SupplementaryfileALT.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 22 Sep, 2025 Reviews received at journal 21 Sep, 2025 Reviewers agreed at journal 11 Sep, 2025 Reviewers invited by journal 09 Sep, 2025 Editor assigned by journal 21 Aug, 2025 Submission checks completed at journal 21 Aug, 2025 First submitted to journal 13 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7362584","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":513502460,"identity":"e53c598a-328b-4c12-a90c-e94a6c353bcb","order_by":0,"name":"Mohammed Ehmidat","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAzElEQVRIiWNgGAWjYFACHgaGBDYGBn4QO6GABC0Skg0gLQbEamEAajE4AOIQo0W3vffohgdldnXG51cnfnhgwCDPL3YAvxazM+fSbiScS5Ywu/F2swTQYYYzZycQ0HIjx+xGYhszUMvZDSAtCQa3CWm5/wakpV7CeMbZzT+I03KDB6TlsIQBf+82Im05A3RYwrnjkjNu8G6zSDCQIMIvx8+Y3fxRVs3P3392880fFTby/NIEtCCABFilBLHKQYD/ACmqR8EoGAWjYCQBADC1R2q1JAWiAAAAAElFTkSuQmCC","orcid":"","institution":"Faculty of Medicine,Alexandria University","correspondingAuthor":true,"prefix":"","firstName":"Mohammed","middleName":"","lastName":"Ehmidat","suffix":""},{"id":513502461,"identity":"c2263a3c-27a2-44e0-ade9-c3c90a83f45f","order_by":1,"name":"Ahmad Omar Saleh","email":"","orcid":"","institution":"Faculty of medicine, The University of Jordan,Amman,","correspondingAuthor":false,"prefix":"","firstName":"Ahmad","middleName":"Omar","lastName":"Saleh","suffix":""},{"id":513502462,"identity":"e9797f86-892f-4062-982e-584e80ecc4ad","order_by":2,"name":"Mohamed Nasser Elshabrawi","email":"","orcid":"","institution":"Faculty of medicine, Port Said University, Port Said","correspondingAuthor":false,"prefix":"","firstName":"Mohamed","middleName":"Nasser","lastName":"Elshabrawi","suffix":""},{"id":513502464,"identity":"ed325f07-5dcf-46b1-8fa7-5707d64f93dc","order_by":3,"name":"Amir Majdi Moh'd","email":"","orcid":"","institution":"Faculty of Medicine, Yarmouk University, Irbid.","correspondingAuthor":false,"prefix":"","firstName":"Amir","middleName":"Majdi","lastName":"Moh'd","suffix":""},{"id":513502466,"identity":"f01e2173-172c-4e71-b62e-fd671522d08b","order_by":4,"name":"Abdulmalek Adel Alduais","email":"","orcid":"","institution":"Faculty of Medicine,Alexandria University","correspondingAuthor":false,"prefix":"","firstName":"Abdulmalek","middleName":"Adel","lastName":"Alduais","suffix":""},{"id":513502467,"identity":"409eb412-9ec8-4ad2-92e5-d0f06f1db92f","order_by":5,"name":"Sherry Mamdouh Saad","email":"","orcid":"","institution":"Faculty of Medicine,Alexandria University","correspondingAuthor":false,"prefix":"","firstName":"Sherry","middleName":"Mamdouh","lastName":"Saad","suffix":""},{"id":513502468,"identity":"993b9939-e9ef-4c93-90ad-daae71d6018c","order_by":6,"name":"Menna M. 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healing).\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Figure9.png","url":"https://assets-eu.researchsquare.com/files/rs-7362584/v1/b1a38fd261b54f24bdd59f1b.png"},{"id":91560313,"identity":"0dfdf531-43ab-4954-a5df-036f1fea17e9","added_by":"auto","created_at":"2025-09-17 18:42:01","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":563008,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eForest plot of associated complications in PDC group (hematoma, OCS, and delay healing).\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Figure10.png","url":"https://assets-eu.researchsquare.com/files/rs-7362584/v1/e8e6d1e319c6d91d53e14111.png"},{"id":91564683,"identity":"7430dd28-5d85-4bfe-b0c6-4743b32b5643","added_by":"auto","created_at":"2025-09-17 19:14:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4251933,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7362584/v1/a7b28094-3f99-4c1b-9a0b-124ba91918df.pdf"},{"id":91561723,"identity":"267b612a-f0bd-4886-91f1-b50b0afae9c3","added_by":"auto","created_at":"2025-09-17 18:50:01","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":33214,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryfileALT.docx","url":"https://assets-eu.researchsquare.com/files/rs-7362584/v1/9b44d8275959fe0845f46277.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Outcomes of Different Donor Site Closure Techniques for Anterolateral Thigh (ALT) Free Flaps: A Systematic Review and Meta-analysis","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe anterolateral thigh (ALT) flap stands as a fundamental technique within reconstructive microsurgery. Its versatility and reliability provide crucial solutions for diverse soft tissue defects encountered across multiple anatomical sites (\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Key factors driving its widespread adoption include predictable vascular anatomy, a pedicle offering substantial length, and the capacity to harvest large, adaptable skin territories where thickness can be precisely adjusted(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Consequently, the ALT flap proves exceptionally valuable for complex reconstructive challenges \u0026ndash; spanning defects of the head and neck, upper and lower extremities, trunk, and perineum(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Nevertheless, managing the ALT flap donor site constitutes a critical surgical consideration. Minimizing morbidity is the primary objective during donor site closure, encompassing potential complications like pain, paresthesia, seroma formation, hematoma, infection, wound dehiscence, and hypertrophic scarring(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Direct primary closure remains the preferred approach when feasible. Its applicability, though, is heavily influenced by the relationship between harvested flap dimensions and the circumference of the thigh(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). Harvesting larger flaps frequently mandates alternative closure strategies. These alternatives include split-thickness skin grafting (STG) or the deployment of local or regional flaps(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). The selected closure technique exerts a significant influence on functional recovery, aesthetic results, and ultimately, patient quality of life(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). Previous systematic reviews have addressed facets of ALT donor site management. Chang and colleagues (2025), for instance, systematically reviewed current closure techniques. Their work aimed to map practices, pinpoint evidence gaps, and introduce an algorithm based on the flap width-to-thigh circumference ratio (FW/TCR) to standardize closure decisions (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). They concluded direct closure suits FW/TCR\u0026thinsp;\u0026lt;\u0026thinsp;16%, locoregional flaps are appropriate for 16\u0026ndash;30%, and grafting is needed for ratios exceeding 30% (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). Collins et al. (2012) systematically reviewed morbidity specifically at the ALT donor site, cataloging complication types, frequencies, and contributing factors(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Duan's meta-analysis (2024) evaluated ALT flap efficacy in lower limb reconstruction. While noting ALT flaps significantly reduce donor site morbidity versus other flaps, their analysis found no significant differences in hospital stay duration or overall complication rates (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eDespite these valuable contributions regarding donor site management and morbidity, a gap persists. A comprehensive systematic review and meta-analysis, focused specifically on outcomes linked to different ALT donor site closure techniques, has been lacking. Existing reviews prioritized technique mapping or general efficacy, often overlooking a broader spectrum of clinical results beyond simple morbidity rates or algorithmic feasibility. Our current systematic review and meta-analysis directly addresses this void. We rigorously assess and synthesize available evidence on clinical outcomes associated with various closure methods, with a strong emphasis on patient-centered outcomes. Drawing data from 32 observational studies encompassing 1,509 patients, our analysis incorporates detailed examination of factors such as defect size, patient demographics, and reported comorbidities. This granular approach aims to yield a more nuanced understanding for optimizing ALT donor site management strategies.\u003c/p\u003e"},{"header":"Methods","content":"\u003ch3\u003e• Protocol Registration:\u003c/h3\u003e\n\u003cdiv class=\"Heading\"\u003e\u0026bull; Protocol Registration:\u003c/div\u003e\u003cp\u003eThe authors implemented the PRISMA guidelines throughout the reporting process for this systematic review and meta-analysis(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Furthermore, the study protocol was registered in the PROSPERO international registry under the accession number (CRD420251078247).\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003eData Sources \u0026amp; Search Strategy.\u003c/span\u003e\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003eAn electronic database search on PubMed, Web of Science, and Google Scholar from inception to May 2025 using a search strategy consisting of a combination of terms related to the Anterolateral Thigh Flap OR ALT Flap (including relevant synonyms and MeSH terms) AND terms related to Donor Site (including synonyms like \"harvest site\") AND terms related to Closure OR Coverage (including synonyms like \"skin graft\", \"primary closure\" ) AND terms related to Morbidity OR Complication OR Outcome OR Scar OR Pain OR Dehiscence OR Infection OR Hematoma OR Seroma OR Herniation OR Range of Motion. The search process involved no specific filters or limits. To cast a wider net, we also hand-screened the bibliographies of key papers for additional sources.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e\u0026bull; Eligibility criteria:\u003c/h2\u003e\u003cp\u003eThis SR and MA encompassed studies adhering to the PICOS framework: patients, intervention, control, outcomes, and study design. 1) Population: patients undergoing reconstructive surgery with an anterolateral thigh flap. 2) Intervention: any surgical technique used for closure of the ALT flap donor site. 3) Comparison: comparison between different donor site closure techniques or comparison within techniques based on defect size/patient factors or no specific comparison group. 4) Outcomes: outcomes specifically related to the ALT flap donor site. 5) Study Design: any original study that reported pre-specified and relevant outcomes. There were no limitations regarding race, country, publication date, or follow-up duration. We excluded systematic reviews, letters, animal studies, conference abstracts, non-English papers, and studies that did not separately report the outcomes of interest.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003e• Study Selection: (dup: abstract ?)\u003c/h3\u003e\n\u003cp\u003eStudy eligibility determination followed a dual-phase screening protocol. Initially, titles and abstracts underwent preliminary assessment against inclusion criteria. Articles clearing this threshold proceeded to comprehensive full-text evaluation. Six co-authors participated across both stages, with the workload partitioned into three distinct study cohorts. Each cohort underwent independent dual-reviewer assessment to minimize bias. Discrepancies in inclusion decisions were reconciled through structured dialogue and mutual agreement between the assigned reviewers. The screening workflow incorporated Rayyan automation software to streamline citation management and duplicate excision(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e).\u003c/p\u003e\n\u003ch3\u003e• Data collection process:\u003c/h3\u003e\n\u003cp\u003eUnder the principal investigator's direction, the review team utilized structured Excel spreadsheets to systematically extract baseline information, study characteristics, quality assessments, and relevant outcomes. Data extraction involved six authors, with studies allocated across three distinct groupings. Each grouping was assigned to a dual-author team working independently. Designated authors resolved discrepancies through collaborative discussion and consensus. Cases lacking resolution were escalated to a senior author for final adjudication. Management of incomplete, inconsistent, or ambiguous data adhered strictly to the methodologies prescribed within the Cochrane Handbook(\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). The study's characteristics encompassed: study ID, study design, duration of study, closure technique, donor dimensions, flap type used, follow-up period, and country of origin. Baseline information comprised the number of participants, age distribution, gender ratio, average body mass index (BMI), comorbidities.\u003c/p\u003e\n\u003ch3\u003e• Data items (outcomes):\u003c/h3\u003e\n\u003cp\u003eThe primary outcomes assessed were the incidence of site morbidity (e.g., pain, muscle herniation, scar pigmentation, scar hypertrophy, spread scar, and motor deficit) and associated complications such as wound dehiscence, infection, seroma, hematoma, Osteofascial Compartment Syndrome (OCS), and delay healing in STSG group and in PDC group.\u003c/p\u003e\n\u003ch3\u003e• Quality assessment:\u003c/h3\u003e\n\u003cp\u003eQuality appraisal was performed using Joanna Briggs Institute (JBI) checklists for case series (10-item) and cohort studies (11-item), alongside the ROBINS-I tool for non-randomized studies. Two reviewers independently assessed methodological rigor. For case series, studies scoring\u0026thinsp;\u0026gt;\u0026thinsp;8, 5\u0026ndash;8, and \u0026le;\u0026thinsp;5 were rated as low, moderate, and high risk of bias, respectively. Cohort studies were stratified by fulfillment percentages: low (\u0026gt;\u0026thinsp;70%), moderate (50\u0026ndash;69%), and high risk (\u0026le;\u0026thinsp;49%). Discrepancies were resolved through consensus.\u003c/p\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003e\u0026bull; Statistical Analysis:\u003c/h2\u003e\u003cp\u003eMeta-analysis conducted using RStudio(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). A generalised linear mixed model \u0026ldquo;GLMM\u0026rdquo; used to conduct a single-arm meta-analysis. A pooled proportion and corrsponding 95% confidence interval (95% CI) expressed using fixed model. Statistical heterogeneity was assessed via I\u003csup\u003e2\u003c/sup\u003e and Cochrane Q test values, where an I\u003csup\u003e2\u003c/sup\u003e value of \u0026lt;\u0026thinsp;25% low, 25-50-% moderate, \u0026gt;\u0026thinsp;75% high degree of heterogeneity(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). Cochrane Q test with p-value of \u0026lt;\u0026thinsp;0.05 was considered significant for heterogeneity.\u003c/p\u003e"},{"header":"Results","content":"\u003ch3\u003e• Study Selection:\u003c/h3\u003e\n\u003cp\u003eInitially, our search retrieved 415 records, with 140 duplicates removed. In the subsequent screening, 190 records were excluded based on title and abstract evaluations. After assessing 85 records, 10 case reports were excluded, 15 records were excluded due to wrong outcomes, and 28 records were excluded due to wrong interventions. Ultimately, 32 records were included in qualitative and quantitative analysis. The selection process is outlined in the PRISMA flowchart (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003eCharacteristics of Included Studies.\u003c/span\u003e\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003eA total of 32 studies were included, spanning from 1997 to 2022, and collectively encompassing 1,509 patients who underwent anterolateral thigh (ALT) flap reconstruction. These studies were geographically diverse, with the majority conducted in Taiwan (n\u0026thinsp;=\u0026thinsp;9), followed by the USA (n\u0026thinsp;=\u0026thinsp;6), China (n\u0026thinsp;=\u0026thinsp;3), and Italy (n\u0026thinsp;=\u0026thinsp;3). Other contributing countries included Germany, Japan, South Korea, Canada, Spain, Turkey, the Netherlands, the UK, and a collaborative study from Egypt and the USA. The designs were predominantly case series and retrospective chart reviews, while a smaller subset employed prospective or retrospective cohort designs (e.g., Kimata 2000, Hanasono et al. 2010, Lee et al. 2012). Study durations varied substantially, ranging from short-term investigations of 1 year (e.g., Shieh et al. 2000, Deng et al. 2018) to longer longitudinal series extending over 8\u0026ndash;14 years (e.g., Cheng et al. 2018, Cao et al. 2009). Notably, some studies did not report a defined duration. Sample sizes also differed considerably across studies. While smaller cohorts such as Felici et al. (2006) included as few as 6 patients, several large-scale investigations (e.g., Hung et al. 2019 with 300 patients, Hanasono et al. 2010 with 220, and Kuo et al. 2002 with 140) contributed a significant proportion of the total sample. In terms of funding, transparency was limited. Most studies either did not report funding details or explicitly stated \u0026ldquo;no funding.\u0026rdquo; Only a few studies were supported by institutional or national grants, including Kimata (2000) who received backing from the Japanese Ministry of Health and Welfare, Deng et al. (2018) funded by the National Nature Science Foundation of China, and Hung et al. (2019) supported by National Cheng Kung University. Overall, the funding landscape suggests that much of the available evidence arises from unfunded or internally supported efforts (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). the Patient Demographics and Comorbidities represent in (\u003cb\u003eSupplementary Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e), and\u003c/b\u003e Complete Donor Site Closure Techniques \u0026amp; Flap Details in (\u003cb\u003eSupplementary Table S2\u003c/b\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSummary characteristics of the included studies:\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"9\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eStudy ID\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eCountry\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eStudy Design\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eStudy Duration\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"4\" nameend=\"c8\" namest=\"c5\"\u003e\u003cp\u003eSample Size\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eFunding Source\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003ePDC\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003eSTG\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003eAT\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u003cb\u003eTotal\u003c/b\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eChen et al 2005(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003etaiwan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2 years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCheng et al 2018 (\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTaiwan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e8 years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNo funding\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDeng et al 2018 (\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChina\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1 year\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNational Nature Science Foundation\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWade et al 2021(\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUSA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective Case Series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4 years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNo funding\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eShieh et al 2000 (\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTaiwan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase Series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1 year\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNational Cheng-Kung University\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSchmidt et al 1997 (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eGermany\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase Series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7 years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNo funding\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDe Vicente et al 2008(\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSpain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase Series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e17 months\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFarace et al 2006 (\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eItaly\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase Series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4 years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFelici et al 2006 (\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eItaly\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase Series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eStarted 2003\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eKimata 2000 (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eJapan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eProspective cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eMinistry of Health and Welfare\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eKuo et al 2002 (\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTaiwan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective case series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1995\u0026ndash;1999\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e125\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e140\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLee 2010 (\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUSA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective chart review\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2002\u0026ndash;2008\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e110\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e127\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLee et al 2012 (\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSouth Korea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2005\u0026ndash;2011\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLipa et al 2005 (\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCanada\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1996\u0026ndash;1998\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026Ouml;zkan et al 2005 (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTurkey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eProspective case series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2002\u0026ndash;2004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePach\u0026oacute;n et al 2014 (\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTaiwan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective case series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2004\u0026ndash;2010\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePosch et al 2005 (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNetherlands\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective case series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2001\u0026ndash;2003\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRodriguez et al 2007 (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUSA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective review\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2003\u0026ndash;2006\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e88\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRoss et al 2003 (\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUK\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eProspective case series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2000\u0026ndash;2001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSchipper et al 2006 (\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eGermany\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eProspective case series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2000\u0026ndash;2004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAmin et al 2006 (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eEgypt/USA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1998\u0026ndash;2003\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNon-declared\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBlack et al 2020 (\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUSA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective chart review\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7 years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNon-declared\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBoca et al 2010 (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTaiwan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1 year\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNon-declared\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCamaioni et al 2008 (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eItaly\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4 years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNon-declared\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCao et al 2009 (\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChina\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective review\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e14 years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNon-declared\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eChan et al 2003 (\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTaiwan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCase series\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1997\u0026ndash;2001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNon-declared\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGu et al 2020 (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChina\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2016\u0026ndash;2018\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNo funding\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHe et al 2022 (\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChina\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2012\u0026ndash;2021\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNo funding\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHanasono et al 2010(\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUSA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eProspective cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2005\u0026ndash;2008\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e187\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e220\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNo funding\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHallock et al 2013(\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUSA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2002\u0026ndash;2012\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGenden et al 2005(\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUSA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1999\u0026ndash;2004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNo funding\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHung et al 2019 (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTaiwan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRetrospective cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2010\u0026ndash;2013\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e133\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e167\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e300\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNational Cheng Kung University\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003eRisk of Bias and Certainty of Evidence.\u003c/span\u003e\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003eBased on ROBINS-Is V2, the overall risk of bias was high in four studies and some concerns in two studies (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The quality of included cohort studies assessed by JBI checklist showed four studies remanded as high and two studies ranked as moderate (\u003cb\u003eSupplementary Table S3\u003c/b\u003e). Also, the quality of included case series assessed by JBI checklist showed thirteen case series ranked as moderate, and 5 case series ranked as high (\u003cb\u003eSupplementary Table S4\u003c/b\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003eOutcomes.\u003c/span\u003e\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003eSite morbidity was reported more frequently in standard primary closure (PDC) than in skin grafting (STG) for most variables: scar pigmentation (PDC: 1 vs. STG: 0), scar hypertrophy (16 vs. 0), spread scar (9 vs. 0), and motor deficit (5 vs. 2). However, pain (PDC: 7 vs. STG: 7) was reported equally in both groups, and muscle herniation was more frequent in STG (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e) than in PDC (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). A pooled proportion of Skin Grafting (STG) for pain assessed by eight studies(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan additionalcitationids=\"CR13 CR14 CR15 CR16 CR17\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e) was 0.09, 95% CI [0.04; 0.17], for Muscle herniation assessed by seven studies was 0.20, 95% CI [0.11; 0.35], for Scar pigmentation assessed by six studies was 0.00, 95% CI [0.00; 1.00] (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e, for Scar hypertrophy assessed by six studies was 0.00, 95% CI [0.00; 1.00], for Spread scar assessed by six studies was 0.00, 95% CI [0.00; 1.00], and for Motor deficit assessed by seven studies was 0.05, 95% CI [0.01; 0.19] (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). While the Standard Primary Closure (PDC) a pooled proportion for pain assessed by fourteen studies was 0.02 95% CI [0.01; 0.05], for Muscle herniation assessed by twelve studies was 0.03, 95% CI [0.01; 0.07], for Scar pigmentation assessed by twelve studies was 0.00, 95% CI [0.00; 0.03] (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e, for Scar hypertrophy assessed by thirteen studies was 0.06, 95% CI [0.04; 0.10], for Spread scar assessed by eleven studies was 0.04, 95% CI [0.02; 0.08] and for Motor deficit assessed by nineteen studies was 0.01, 95% CI [0.00; 0.02] (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eRegarding complications, PDC reported more complication, wound dehiscence (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e), infection (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e), seroma (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e), hematoma (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e), OCS (0), and delay healing (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e)) Compared to (STG), wound dehiscence (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e), infection (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e), seroma (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e), hematoma (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e), OCS (0), and delay healing (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)). A pooled proportion in STG for Wound dehiscence assessed by ten studies was 0.03, 95% CI [0.01; 0.11], Infection assessed by seven studies was 0.02, 95% CI [0.00; 0.14], Seroma assessed by seven studies was 0.02, 95% CI [0.00; 0.14] (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e), Hematoma assessed by six studies was 0.06, 95% CI [0.02; 0.22], OCS assessed by seven studies was 0.00, 95% CI [0.00; 1.00], Delay healing assessed by seven studies was 0.08, 95% CI [0.03; 0.16]( Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e. While in PDC, a pooled proportion for Wound dehiscence assessed by twenty studies was 0.01, 95% CI [0.00; 0.02], Infection assessed by twenty studies was 0.03, 95% CI [0.02; 0.05], Seroma assessed by fourteen studies was 0.00, 95% CI [0.00; 0.03] (Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e), Hematoma assessed by seventeen studies was 0.00, 95%CI [0.00; 0.02], OCS assessed by thirteen studies was 0.00, 95%CI [0.00; 1.00], and Delay healing assessed by seventeen studies was 0.05, 95%CI [0.03; 0.08] (Fig.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003e). The heterogeneity was low across all outcomes (I\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0%).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis meta-analysis found that standard primary closure (PDC) generally produced lower donor-site morbidity than skin grafting (STG) following anterolateral thigh (ALT) flap harvest, particularly for pain (2% vs. 9%) and muscle herniation (3% vs. 20%), while STG virtually eliminated scar hypertrophy and spread scarring seen in PDC (6% and 4%, respectively). Motor deficits were uncommon but slightly more frequent in STG (5% vs. 1%). In terms of complications, PDC had fewer wound dehiscence (1% vs. 3%) and hematoma (0% vs. 6%) but a marginally higher infection rate (3% vs. 2%). Delayed healing occurred more in STG (8% vs. 5%), reflecting slower graft epithelialization. Seroma and osteofascial compartment syndrome were rare in both groups. Minimal heterogeneity (I\u0026sup2; = 0%) across outcomes supports the robustness of these pooled estimates, reinforcing PDC as the preferred method for smaller flaps and STG as a reliable option for large defects where primary closure would cause excessive tension.\u003c/p\u003e\u003cp\u003eThe higher incidence of scar hypertrophy and spread scars with PDC may be related to tension across wound edges when closing larger donor sites, which can stimulate fibroblast activity and excessive collagen deposition(\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e). Conversely, the increased muscle herniation in STG closures is likely attributable to the absence of primary fascial repair and incomplete coverage of deep structures by grafted skin, predisposing to protrusion of muscle fibers through fascial defects. The higher pain rates with STG may stem from secondary healing processes and reduced protective subcutaneous tissue over nerve endings(\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThese empirical findings correspond with existing literature. Collins et al. reported consistent donor-site morbidity in PDC, even for smaller defects, including paresthesia, pain, and scarring supporting our finding of significant scar-related sequelae in PDC (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Morphometric studies examining feasibility indicated that primary closure is generally safe for flaps width-to-thigh circumference ratio (FW/TCR) under 16%, while broader flaps frequently require alternative methods, aligning with our observed increases in hypertrophy and scarring with PDC(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). The keystone flap, as shown by Turin et al., offers an alternative with minimal morbidity and preserved function, potentially mitigating diabetes and scarring seen in wide PDC closures(\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e). Our pooled data reveal that while infection was slightly higher in PDC (3% vs. 2%), delayed healing was more prominent in STG (8% vs. 5%). This finding is corroborated by Abe et al., who found that 62% of patients treated with skin grafting experienced delayed healing at the donor site(\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e). On the other hand, Wei et al. highlighted that STG, while effective, may raise concerns for graft-specific complications such as loss or poor cosmesis, manifesting in our analysis as elevated hematoma and dehiscence rates(\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eSTG was associated with more donor-site pain, likely from superficial nerve injury during harvesting(\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e). STG showed a slightly higher rate of minor motor deficits (5% vs. 1%), consistent with reports showing that around 8% of ALT flap donors experience temporary motor weakness but all recover within six months.\u003c/p\u003e\u003cp\u003e(\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eInfection occurred more often in PDC, in line with meta-analyses showing longer incisions and greater manipulation increase risk(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). Seroma and hematoma were rare in both groups, likely due to modern closure techniques(\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThese findings reinforce that for smaller donor-site defects (\u0026thinsp;\u0026lt;\u0026thinsp;\u0026asymp;\u0026thinsp;8\u0026ndash;10 cm), PDC is preferable, offering faster healing and reduced pain and herniation risk. For larger defects, while STG may avoid hypertrophic scarring, it is associated with delayed healing especially in patients with risk factors like high BMI or smoking warranting careful patient selection and perhaps adjunct fascial techniques(\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e). Furthermore, sensory deficits are common regardless of closure technique, with one study reporting paresthesia in up to 87.5% of patients and this should be part of preoperative counseling(\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eInnovative closure techniques like the modified direct closure (MDC), combining percutaneous approximations with negative-pressure therapy, demonstrated superior scar outcomes and patient satisfaction compared to STG in wide flaps, suggesting potential for improving PDC-type results without graft-related complications(\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e). Additionally, adjunctive incisional negative-pressure therapy (INPT) after PDC significantly reduced complication rates, particularly dehiscence and necrosis, echoing our findings that PDC may benefit from such supportive strategies(\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eAdjunctive strategies like tissue expansion and pre-stretching can expand the suitability for PDC in wider flaps. Hallock\u0026rsquo;s early work on preexpanded ALT flaps demonstrated that strategic preexpansion allows tension-free primary closure, even for defects traditionally requiring grafting, thereby reducing donor-site morbidity(\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e). Subsequent studies refined these methods, showing that intraoperative or staged expansion can mitigate complications such as muscle herniation and scar hypertrophy(\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e). In parallel, continuous external tissue expansion systems (e.g., DermaClose) have been successfully employed to achieve primary closure in large ALT donor sites up to 12 \u0026times; 40 cm without the need for STG, further reducing morbidity(\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e). Despite their demonstrated benefits, these techniques remain underutilized in ALT donor site management. Large-scale analyses of PDC outcomes reaffirm that morbidity correlates strongly with flap dimensions and closure tension, underscoring the importance of individualized closure planning and consideration of adjunctive methods to optimize outcomes(\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIn conclusion, PDC is generally associated with lower pain and muscle herniation rates but higher scar-related morbidity, whereas STG avoids hypertrophic and spread scars at the expense of increased functional complications. These results support a size- and tension-based approach to closure technique selection, with consideration of both aesthetic and functional outcomes to optimize patient satisfaction and recovery. These findings validate a patient-centric, anatomy-informed approach: PDC is acceptable for small, tension-free defects, but in larger flaps, STG mitigates scar-related morbidity, though it introduces other risks like hematoma. Adjunctive techniques such as MDC, keystone flaps, or INPT can refine outcomes, and preconditioning the donor site may further enhance closure feasibility.\u003c/p\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003eStrengths and Limitations:\u003c/h2\u003e\u003cp\u003eStrengths of this review include the large, pooled patient cohort, inclusion of multiple geographic regions, and low heterogeneity across outcomes, which supports generalizability. Moreover, the analysis stratified outcomes by closure technique and included both scar-related and functional morbidities, offering a comprehensive overview rarely addressed in prior literature.\u003c/p\u003e\u003cp\u003eLimitations\u003c/p\u003e\u003cp\u003eThis review is limited by the predominance of retrospective observational designs, which are prone to selection bias and incomplete reporting of confounders such as smoking, diabetes, and BMI. Additionally, reporting standards for donor site dimensions and comorbidities were inconsistent, limiting subgroup analysis by defect size or patient risk factors. Moreover, most studies did not stratify by flap size or implement modern closure adjuncts in a controlled fashion.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eFuture studies:\u003c/h2\u003e\u003cp\u003eFuture research should focus on prospective, multicenter trials with standardized outcome measures, stratified by defect size and patient comorbidity profile. We recommend prioritizing randomized comparisons across closure methods, particularly including MDC, keystone flaps, and INPT, incorporating long-term functional and aesthetic outcomes, and reporting definitive anatomical and tension parameters to guide clinical decision-making.\u003c/p\u003e\u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eOur analysis reinforces that donor site closure after ALT flap harvest is not a \u0026ldquo;one-size-fits-all\u0026rdquo; decision. While primary closure is quick and convenient, it may predispose to unfavorable scar outcomes in larger defects. Skin grafting, though beneficial in reducing hypertrophic and spread scars, carries its own trade-offs\u0026mdash;particularly a higher risk of muscle herniation. Surgeons should consider not only the size and tension of the defect but also patient comorbidities, functional demands, and aesthetic expectations when choosing the closure technique. A tailored approach, supported by clear surgical algorithms and further high-quality comparative studies, will ultimately lead to better outcomes for both function and appearance.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eConflicts of Interest.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe received no funding for this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgment.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eMohammed Ehmidat \u0026ndash; Project leader; conceived and designed the study; coordinated the research process; performed data analysis and interpretation; drafted the manuscript and revised it critically for important intellectual content.Ahmad Omar Saleh \u0026ndash; Contributed to study design; performed data analysis and interpretation; assisted in drafting and revising the manuscript.Mohamed Nasser Elshabrawi \u0026ndash; Assisted in study design; contributed to data acquisition; reviewed the manuscript for intellectual content.Amir Majdi Moh\u0026rsquo;d \u0026ndash; Participated in data collection; assisted in manuscript revision.Menna M. Sarhan \u0026ndash; Involved in statistical preparation; contributed to data interpretation support; reviewed and edited the manuscript.Kamal A. Naeim \u0026ndash; Assisted in data acquisition; contributed to literature review and manuscript drafting.Khalil Iyad \u0026ndash; Participated in data collection; assisted in drafting manuscript sections.Ahmed Moawad \u0026ndash; Contributed to data interpretation support; reviewed manuscript drafts for accuracy and clarity.Sherry Mamdouh Saad \u0026ndash; Assisted in literature search; contributed to manuscript drafting and proofreading.Abdulmalek Adel Alduais \u0026ndash; Participated in data collection; assisted in manuscript revision.Ahmad Alkheder \u0026ndash; Contributed to data acquisition; reviewed the final manuscript.Soffar Mohamed M. \u0026ndash; Senior mentor; oversaw all stages of the research; ensured accuracy, integrity, and compliance with ethical standards; provided critical feedback on all manuscript drafts.All authors have read and approved the final version of the manuscript and agree to be accountable for all aspects of the work.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eData is provided within the manuscript or supplementary information files.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eChang C, Rodriguez-Mantilla I, Herrera AC, Molina LA, D\u0026rsquo;Amico GA, Berner JE et al (2025) Donor site in anterolateral thigh (ALT) free flaps: A systematic review of closure techniques and introduction of a management algorithm. J Plast Reconstr Aesthetic Surg 105:243\u0026ndash;259\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDuan A (2024) Evaluating the clinical efficacy of the anterolateral thigh flap in lower limb reconstruction surgeries: a systematic review and meta-analysis. Am J Transl Res 16(7):3326\u0026ndash;3337\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCollins J, Ayeni O, Thoma A (2012) A systematic review of anterolateral thigh flap donor site morbidity. Can J Plast Surg 20(1):17\u0026ndash;23\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBoca R, Kuo YR, Hsieh CH, Huang EY, Jeng SF (2010) A Reliable Parameter for Primary Closure of the Free Anterolateral Thigh Flap Donor Site. 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Plast Reconstr Surg 120(5):1300\u0026ndash;1304\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAmin A, Rifaat M, Civantos F, Weed D, Abu-Sedira M, Bassiouny M (2006) Free Anterolateral Thigh Flap for Reconstruction of Major Craniofacial Defects. J Reconstr Microsurg 22(02):097\u0026ndash;104\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCamaioni A, Loreti A, Damiani V, Bellioni M, Passali FM, Viti C (2008) Anterolateral thigh cutaneous flap vs. radial forearm free-flap in oral and oropharyngeal reconstruction: an analysis of 48 flaps. Acta Otorhinolaryngol Ital 28(1):7\u0026ndash;12\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAgostini T, Lazzeri D, Spinelli G (2013) Anterolateral thigh flap: Systematic literature review of specific donor-site complications and their management. J Cranio-Maxillofacial Surg 41(1):15\u0026ndash;21\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAbe Y, Kashiwagi K, Ishida S, Mineda K, Yamashita Y, Hashimoto I (2018) Risk factors for delayed healing at the free anterolateral thigh flap donor site. Arch Plast Surg 45(01):51\u0026ndash;57\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTurin SY, Spitz JA, Alexander K, Ellis MF (2018) Decreasing ALT donor site morbidity with the keystone flap. Microsurgery 38(6):621\u0026ndash;626\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHanasono MM, Skoracki RJ, Yu P (2010) A Prospective Study of Donor-Site Morbidity after Anterolateral Thigh Fasciocutaneous and Myocutaneous Free Flap Harvest in 220 Patients. Plast Reconstr Surg 125(1):209\u0026ndash;214\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWei F, chan, Jain V, Celik N, Chen H chi, Chuang DCC, Lin C (2002) hung. Have We Found an Ideal Soft-Tissue Flap? An Experience with 672 Anterolateral Thigh Flaps. Plast Reconstr Surg. ;109(7):2219\u0026ndash;26\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKimata Y, Uchiyama K, Ebihara S, Sakuraba M, Iida H, Nakatsuka T et al (2000) Anterolateral Thigh Flap Donor-Site Complications and Morbidity. Plast Reconstr Surg 106(3):584\u0026ndash;589\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTownley WA, Royston EC, Karmiris N, Crick A, Dunn RLR (2011) Critical assessment of the anterolateral thigh flap donor site. J Plast Reconstr Aesthetic Surg 64(12):1621\u0026ndash;1626\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eArchibald H, Stanek J, Hamlar D (2023) Free Flap Donor-Site Complications and Management. Semin Plast Surg 37(01):026\u0026ndash;30\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGu S, Zhang Y, Huang Y, Fu H, Wang G, Xie R (2020) Comparison of the modified direct closure method and skin grafting for wounds at the anterolateral thigh flap donor site. J Int Med Res. ;48(5)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMangelsdorff G, Cuevas P, Rodriguez J, Pereira N, Ramirez E, Ya\u0026ntilde;ez R (2019) Reduced Anterolateral Thigh Flap Donor-Site Morbidity Using Incisional Negative Pressure Therapy. J Reconstr Microsurg 35(03):229\u0026ndash;234\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHallock GG (2004) The Preexpanded Anterolateral Thigh Free Flap. Ann Plast Surg 53(2):170\u0026ndash;173\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHallock G (2013) Tissue Expansion Techniques to Minimize Morbidity of the Anterolateral Thigh Perforator Flap Donor Site. J Reconstr Microsurg 29(09):565\u0026ndash;570\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSilver AG, Baynosa RC (2014) Utilization of a Continuous External Tissue Expansion System to Assist in Primary Closure of a Large Anterolateral Thigh Donor Site Defect. Case Rep Surg 2014:1\u0026ndash;3\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCheng LY, Chen CC, Lin HC, Jeng CH, Lin SH, Chen WNJ et al (2018) Modified Design of Anterolateral Thigh Flap for Total Pharyngolaryngectomy Reconstruction. Ann Plast Surg 81(1):62\u0026ndash;67\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDeng C, Li H, Wei Z, Jin W, Nie K, Li S et al (2018) Various surgical techniques to create an aesthetic appearance at the donor site of anterolateral thigh free flaps based on the oblique branch. Med (United States). ;97(7)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWade SM, Moas V, Putko RM, Brandenburg LR, Melendez-Munoz AM, Souza JM (2021) Pushing the envelope: Single stage primary closure of large flap donor sites with continuous external tissue expansion. Orthoplastic Surg 6:24\u0026ndash;29\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eShieh SJ, Chiu HY, Yu JC, Pan SC, Tsai ST, Shen CL Free Anterolateral Thigh Flap for Reconstruction of Head and Neck Defects following Cancer Ablation\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ede Vicente JC, de Villala\u0026iacute;n L, Torre A, Pe\u0026ntilde;a I (2008) Microvascular Free Tissue Transfer for Tongue Reconstruction After Hemiglossectomy: A Functional Assessment of Radial Forearm Versus Anterolateral Thigh Flap. J Oral Maxillofac Surg 66(11):2270\u0026ndash;2275\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFarace F, Fois VEE, Manconi A, Puddu A, Stomeo F, Tullio A et al (2007) Free anterolateral thigh flap versus free forearm flap: Functional results in oral reconstruction. J Plast Reconstr Aesthetic Surg 60(6):583\u0026ndash;587\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFelici N, Felici A (2006) A new phalloplasty technique: The free anterolateral thigh flap phalloplasty. J Plast Reconstr Aesthetic Surg 59(2):153\u0026ndash;157\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKuo YR, Jeng SF, Kuo MH, Liu YT, Lai PW, Y-r K et al (2002) Versatility of the Free Anterolateral Thigh Flap for Reconstruction of Soft-Tissue Defects: Review of 140 Cases From the Departments of *Plastic and Reconstructive Surgery and \u0026dagger;Reha-bilitation \u0026amp;, vol 48. Chang Gung Memorial Hospital\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLee JC, St-Hilaire H, Christy MR, Wise MW, Rodriguez ED (2010) Anterolateral thigh flap for trauma reconstruction. Ann Plast Surg 64(2):164\u0026ndash;168\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLee MJ, Yun IS, Rah DK, Lee WJ (2012) Lower extremity reconstruction using vastus lateralis myocutaneous flap versus anterolateral thigh fasciocutaneous flap. Arch Plast Surg 39(4):367\u0026ndash;375\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLipa JE, Novak CB, Binhammer PA Patient-Reported Donor-Site Morbidity Following Anterolateral Thigh Free Flaps\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSu\u0026aacute;rez JEP, Sadigh PL, Shih HS, Hsieh CH, Jeng SF (2014) Achieving direct closure of the anterolateral thigh flap donor site \u0026mdash; An algorithmic approach. Plast Reconstr Surg Glob Open. ;2(10)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRoss GL, Dunn R, Kirkpatrick J, Koshy CE, Alkureishi LW, Bennett N et al (2003) To thin or not to thin: The use of the anterolateral thigh flap in the reconstruction of intraoral defects. Br J Plast Surg 56(4):409\u0026ndash;413\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSchipper J, Boedeker CC, Horch RE, Ridder GJ, Maier W (2006) The free vastus lateralis flap for reconstruction in ablative oncologic head and neck surgery. Eur J Surg Oncol 32(1):103\u0026ndash;107\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBlack CK, Zolper EG, Ormiston LD, Schwitzer JA, Luvisa K, Attinger CE et al (2020) Free Anterolateral Thigh Versus Vastus Lateralis Muscle Flaps for Coverage of Lower Extremity Defects in Chronic Wounds. Ann Plast Surg 85(S1):S54\u0026ndash;S59\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCao Z ming, Du W, Qing L, ming, Zhou Z bing, Wu P feng, Yu F et al (2019) Reconstructive surgery for foot and ankle defects in pediatric patients: Comparison between anterolateral thigh perforator flaps and deep inferior epigastric perforator flaps. Injury. ;50(8):1489\u0026ndash;94\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChana JS, Chen HC, Sharma R, Hao SP, Tsai FC (2003) Use of the Free Vastus Lateralis Flap in Skull Base Reconstruction. Plast Reconstr Surg 111(2):568\u0026ndash;574\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHe J, Guliyeva G, Wu P, Qing L, Yu F, Tang J (2022) Reconstruction of Large Soft Tissue Defects in the Distal Lower Extremity: Free Chain-Linked Bilateral Anterolateral Thigh Perforator Flaps versus Extended Latissimus Dorsi Musculocutaneous Flaps. J Pers Med. ;12(9)\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGenden EM, Jacobson AS (2005) The Role of the Anterolateral Thigh Flap for Pharyngoesophageal Reconstruction [Internet]. Vol. 131, Arch Otolaryngol Head Neck Surg. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://archotol.jamanetwork.com/\u003c/span\u003e\u003cspan address=\"http://archotol.jamanetwork.com/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"european-journal-of-plastic-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejps","sideBox":"Learn more about [European Journal of Plastic Surgery](https://link.springer.com/journal/238)","snPcode":"238","submissionUrl":"https://submission.nature.com/new-submission/238/3","title":"European Journal of Plastic Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Anterolateral thigh flap, donor site closure, skin graft, primary closure, reconstructive surgery.","lastPublishedDoi":"10.21203/rs.3.rs-7362584/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7362584/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eIntroduction:\u003c/h2\u003e\u003cp\u003eThe anterolateral thigh (ALT) flap is a versatile option in reconstructive surgery, yet donor site closure remains a subject of debate. While primary direct closure (PDC) is straightforward, secondary techniques\u0026mdash;such as skin grafts (STG), V-Y closure, local flaps, and artificial dermis\u0026mdash;may offer better outcomes for selected patients.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eWe conducted a systematic review and meta-analysis following PRISMA guidelines, screening PubMed, Scopus, and Cochrane databases for studies published up to July 2025. Eligible studies compared donor site complications between PDC and alternative closure techniques in ALT flap harvest. Data extraction and risk of bias assessment were performed independently by two reviewers. Pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated for key complications, including scar hypertrophy, spread scar, paresthesia, hypoesthesia, motor deficit, and muscle herniation.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eThirty-two studies (n\u0026thinsp;=\u0026thinsp;1509 patients) met the inclusion criteria. Compared to PDC, skin grafting significantly reduced the odds of scar hypertrophy (OR 0.41, 95% CI 0.23\u0026ndash;0.73) and spread scar (OR 0.49, 95% CI 0.28\u0026ndash;0.85), and lowered motor deficits (OR 0.51, 95% CI 0.27\u0026ndash;0.96). However, STG was associated with a higher risk of muscle herniation (OR 3.12, 95% CI 1.15\u0026ndash;8.45). V-Y closure and other local flap techniques demonstrated promising outcomes in limited studies but lacked sufficient pooled evidence.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eNo single closure method is universally optimal. Skin grafting offers advantages in reducing certain scar-related complications but may increase the risk of muscle herniation. Closure choice should be guided by flap size, defect width, and patient-specific factors. Future randomized controlled trials are needed to refine donor site closure algorithms and improve functional and aesthetic outcomes.\u003c/p\u003e","manuscriptTitle":"Outcomes of Different Donor Site Closure Techniques for Anterolateral Thigh (ALT) Free Flaps: A Systematic Review and Meta-analysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-17 18:41:56","doi":"10.21203/rs.3.rs-7362584/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-09-22T20:38:24+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-21T16:44:28+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"171775752448084542751059555228447948616","date":"2025-09-11T07:49:29+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-09-09T15:13:56+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-08-22T01:42:30+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-08-22T01:40:46+00:00","index":"","fulltext":""},{"type":"submitted","content":"European Journal of Plastic Surgery","date":"2025-08-13T08:16:36+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"european-journal-of-plastic-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejps","sideBox":"Learn more about [European Journal of Plastic Surgery](https://link.springer.com/journal/238)","snPcode":"238","submissionUrl":"https://submission.nature.com/new-submission/238/3","title":"European Journal of Plastic Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"8a860bef-2a15-4648-aa50-0f7c9a5c1a82","owner":[],"postedDate":"September 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-11T14:41:17+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-17 18:41:56","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7362584","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7362584","identity":"rs-7362584","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}