Free fibula mandible reconstruction for osteoradionecrosis is more challenging than for primary cancer.

INTRODUCTION: Osteoradionecrosis (ORN) of the mandible is an unfortunate potential sequela of radiotherapy for head and neck cancer. In advanced cases of ORN, mandibulectomy, and free fibula flap reconstruction are required. We hypothesized that patients undergoing fibula free flap reconstruction and mandibulectomy for ORN pose unique challenges and experience more complications than patients undergoing fibula free flaps after oncologic mandibulectomy. METHODS: After IRB approval, we created a database of all free fibula flaps for mandible reconstruction from April 2005 through February 2019. Medical records were retrospectively reviewed for patient and surgical characteristics and postoperative outcomes. RESULTS: Four-hundred seventy-nine patients met the inclusion criteria (168 ORN vs. 311 non-ORN patients). Propensity-matching was performed based on age, BMI, smoking status, preoperative chemotherapy, and virtual surgery planning use, which yielded 159 patients in each group. ORN patients received more double-skin-island fibula flaps than non-OR patients (20.8% vs. 5.7%, p < 0.001). Recipient artery other than the facial artery was utilized more commonly in ORN patients (42.1% vs. 17.0%, p < 0.001). In the unmatched cohort, ORN patients had higher rates of delayed wound healing (26.2% vs. 16.8%, p = 0.01) and surgical site infections (21.4% vs. 13.2%, p = 0.02). Rates of flap loss, return to the operating room, hematoma, operative time, and length of stay were similar between the groups. On logistic regression analysis, osteoradionecrosis was an independent risk factor for delayed wound healing. CONCLUSION: Based on these data, mandibular reconstruction with fibula flaps for osteoradionecrosis appears more complicated than mandible reconstruction following de novo cancer resection. Surgeons should anticipate employing two skin islands for intraoral and extraoral resurfacing, utilizing unconventional recipient vessels, and managing the delayed wound healing that ensues more commonly than non-ORN patients.

Expanding the Armamentarium of Donor Sites in Microvascular Head and Neck Reconstruction.

The field of microsurgical head and neck reconstruction has witnessed tremendous advancements in recent years. While the historic goals of reconstruction were simply to maximize flap survival, optimizing both aesthetic and functional outcomes has now become the priority. With an increased understanding of perforator anatomy, improved technology in instruments and microscopes, and high flap success rates, the reconstructive microsurgeon can push the envelope in harvesting and designing the ideal flap to aid patients following tumor extirpation. Furthermore, with improvements in cancer treatment leading to improved patient survival and prognosis, it becomes increasingly important to have a broader repertoire of donor sites. The present review aims to provide a review of newly emerging soft tissue flap options in head and neck reconstruction. While certainly a number of bony flap options also exist, the present review will focus on soft tissue flaps that can be harvested reliably from a variety of alternate donor sites. From the upper extremity, the ulnar forearm as well as the lateral arm, and from the lower extremity, the profunda artery perforator, medial sural artery perforator, and superficial circumflex iliac perforator flaps will be discussed, and we will provide details to aid reconstructive microsurgeons in incorporating these alternative flaps into their armamentarium.

Outcomes for 160 Consecutive Lateral Arm Free Flaps for Head and Neck Reconstruction.

OBJECTIVE: Examine outcomes for lateral arm autologous tissue transfer in head and neck reconstruction. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary cancer center. METHODS: All patients who underwent traditional lateral arm, extended lateral arm, and lateral forearm flaps for head and neck reconstruction from 2012 to 2022 were assessed. Disabilities of the arm, shoulder, and hand (DASH) was measured. Factors associated with complications and enteral or mixed diet were evaluated by multivariable regression. RESULTS: Among 160 patients followed for a median of 2.3 ± 2.1 years, defects were 54% oral tongue, 18% external, 9% maxilla, 8% buccal mucosa, 9% floor of mouth, and 3% pharynx. Flap types (and median pedicle lengths) were 41% traditional lateral arm (8 cm), 25% extended lateral arm (11.5 cm), and 34% lateral forearm (14 cm). All donor sites were closed primarily; 19.6% and 0% of patients had increased DASH scores 2 and 12 weeks after reconstruction. Major complications occurred in 18.1% of patients, including 6.3% reoperation, 6.9% readmission, 3.7% fistula, and 1.8% flap loss. Complications were independently associated with peripheral vascular disease (odds ratio [OR]: 5.71, 95% confidence interval [CI]: 1.5-21.6, P = .01), pharyngeal defects (OR: 11.3, 95% CI: 1.4-94.5, P = .025), and interposition vein grafts (OR: 3.78, 95% CI: 1.1-13.3, P = .037). CONCLUSION: The lateral arm free flap was safe, versatile, and reliable for head and neck reconstruction with low donor-site morbidity. Complications occurred in a fifth of patients and were associated with peripheral vascular disease, pharyngeal defects, and vein grafts.

A systematic review and meta-analysis of the clinimetric properties of the core outcome measurement instruments for clinical effectiveness trials of nutritional and metabolic interventions in critical illness (CONCISE).

BACKGROUND: CONCISE is an internationally agreed minimum set of outcomes for use in nutritional and metabolic clinical research in critically ill adults. Clinicians and researchers need to be aware of the clinimetric properties of these instruments and understand any limitations to ensure valid and reliable research. This systematic review and meta-analysis were undertaken to evaluate the clinimetric properties of the measurement instruments identified in CONCISE. METHODS: Four electronic databases were searched from inception to December 2022 (MEDLINE via Ovid, EMBASE via Ovid, CINAHL via Healthcare Databases Advanced Search, CENTRAL via Cochrane). Studies were included if they examined at least one clinimetric property of a CONCISE measurement instrument or recognised variation in adults ≥ 18 years with critical illness or recovering from critical illness in any language. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist for systematic reviews of Patient-Reported Outcome Measures was used. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were used in line with COSMIN guidance. The COSMIN checklist was used to evaluate the risk of bias and the quality of clinimetric properties. Overall certainty of the evidence was rated using a modified Grading of Recommendations, Assessment, Development and Evaluation approach. Narrative synthesis was performed and where possible, meta-analysis was conducted. RESULTS: A total of 4316 studies were screened. Forty-seven were included in the review, reporting data for 12308 participants. The Short Form-36 Questionnaire (Physical Component Score and Physical Functioning), sit-to-stand test, 6-m walk test and Barthel Index had the strongest clinimetric properties and certainty of evidence. The Short Physical Performance Battery, Katz Index and handgrip strength had less favourable results. There was limited data for Lawson Instrumental Activities of Daily Living and the Global Leadership Initiative on Malnutrition criteria. The risk of bias ranged from inadequate to very good. The certainty of the evidence ranged from very low to high. CONCLUSIONS: Variable evidence exists to support the clinimetric properties of the CONCISE measurement instruments. We suggest using this review alongside CONCISE to guide outcome selection for future trials of nutrition and metabolic interventions in critical illness. TRIAL REGISTRATION: PROSPERO (CRD42023438187). Registered 21/06/2023.

Innovative Strategies in Microvascular Head and Neck Reconstruction.

The field of reconstructive microsurgery has witnessed considerable advancements over the years, driven by improvements in technology, imaging, surgical instruments, increased understanding of perforator anatomy, and experience with microsurgery. However, within the subset of microvascular head and neck reconstruction, novel strategies are needed to improve and optimize both patient aesthetics and post-operative function. Given the disfiguring defects that are encountered following trauma or oncologic resections, the reconstructive microsurgeon must always aim to innovate new approaches, reject historic premises, and challenge established paradigms to further achieve improvement in both aesthetic and functional outcomes. The authors aim to provide an up-to-date review of innovations in head and neck reconstruction for oncologic defects.

Association of dengue serotypes and its complications: a retrospective cohort study.

INTRODUCTION: Dengue fever is an arthropod-borne disease and has a wide clinical spectrum. It is hypothesised that dengue serotypes could be a possible factor for such phenomena and therefore be a possible predictor for the development of severe dengue. METHOD: A retrospective cohort study was done to explore the association between dengue serotypes and the various complications. All patients who underwent dengue serotyping from 1st January to 31st December 2018 in Tengku Ampuan Rahimah Hospital were selected. Serotypes were randomly done for admitted dengue patients. Notes were then retrieved for data collection. Secondary outcomes like length of stay and highest lactate level were also studied. Data analysis was done using SPSS version 20. RESULT: A total of 193 patient records were included in the analysis. Chi-square test for independence indicated that the proportion of dengue complications between male and female were significantly different (χ2(1) = 11.37, p = 0.001). Dengue serotype was not associated with the development of dengue complications, total number of dengue complications, length of admission, lactate level and survival among the serotypes. Results of the binary logistic regression showed that men have thrice the odds (AOR = 3.3, 95% CI: 1.6 6.7) for developing dengue complications. One patient was found to be co-infected with serotype 2 and 3. CONCLUSION: Our study did not reveal any association between the different dengue virus serotypes and its complications. Therefore, all dengue infection should be approached with equal meticulousness. There are possibilities that apart from serotype, dengue genotype and lineage would determine clinical outcome. However, more studies are required to study such associations.

Pharyngeaoesophageal Reconstruction.

Pharyngoesophageal reconstruction is one of the most challenging reconstructive dilemmas that demands extensive planning, meticulous surgical execution, and timely management of postoperative complications. The main goals of reconstruction are to protect critical blood vessels of the neck, to provide alimentary continuity, and to restore functions such as speech and swallowing. With the evolution of techniques, fasciocutaneous flaps have become the gold standard for most defects in this region. Major complications include anastomotic strictures and fistulae, but most patients can tolerate an oral diet and achieve fluent speech after rehabilitation with a tracheoesophageal puncture.

Assessing saliency models of observers' visual attention on acquired facial differences.

Purpose: Saliency models that predict observers' visual attention to facial differences could enable psychosocial interventions to help patients and their families anticipate staring behaviors. The purpose of this study was to assess the ability of existing saliency models to predict observers' visual attention to acquired facial differences arising from head and neck cancer and its treatment. Approach: Saliency maps predicted by graph-based visual saliency (GBVS), an artificial neural network (ANN), and a face-specific model were compared to observer fixation maps generated from eye-tracking of lay observers presented with clinical facial photographs of patients with a visible or functional impairment manifesting in the head and neck region. We used a linear mixed-effects model to investigate observer and stimulus factors associated with the saliency models' accuracy. Results: The GBVS model predicted many irrelevant regions (e.g., shirt collars) as being salient. The ANN model underestimated observers' attention to facial differences relative to the central region of the face. Compared with GBVS and ANN, the face-specific saliency model was more accurate on this task; however, the face-specific model underestimated the saliency of deviations from the typical structure of human faces. The linear mixed-effects model revealed that the location of the facial difference (midface versus periphery) was significantly associated with saliency model performance. Model performance was also significantly impacted by interobserver variability. Conclusions: Existing saliency models are not adequate for predicting observers' visual attention to facial differences. Extensions of face-specific saliency models are needed to accurately predict the saliency of acquired facial differences arising from head and neck cancer and its treatment.

Introduction of the L-PAP Flap: Bipedicled, Conjoined, and Stacked Thigh-Based Flaps for Autologous Breast Reconstruction.

SUMMARY: Thigh-based flaps are increasingly popular options for autologous breast reconstruction in the setting of abdominal donor-site inadequacy, previous surgery, or patient preference, but the volume and skin associated with these flaps are often lacking relative to the abdomen. An individualized, shared decision-making approach to donor-site selection was adopted based on body shape, surgical history, lifestyle, reconstructive needs, and patient expectations. Different thigh-based flaps combined in stacked, bipedicled, or conjoined configurations were selected to maximize efficient use of available soft-tissue skin and volume while optimizing donor-site aesthetics. A total of 23 thigh-based stacked, bipedicled, or conjoined profunda artery perforator (PAP), lateral thigh perforator (LTP), or gracilis musculocutaneous flap components were used in six patients. Configurations included bilateral stacked PAP and LTP flaps, bipedicled posterolateral thigh flaps based on the LTP and PAP (L-PAP), and bipedicled thigh flaps based on the gracilis and PAP pedicles. Most anastomoses were performed to the antegrade and retrograde internal mammary vessels; intraflap anastomoses were performed in one case. There were no partial or total flap losses. There was one donor-site seroma. Design of stacked, bipedicled, and conjoined thigh-based flaps using multiple conventional flap components allows for tailored approaches to donor-site utilization based on individual body shape in selected patients. Bipedicled design with the L-PAP flap represents one strategy in appropriate cases to overcome skin and volume deficiencies while facilitating coning and projection. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Updates in Traumatic Lower Extremity Free Flap Reconstruction.

SUMMARY: Lower extremity reconstruction, particularly in the setting of trauma, remains one of the most challenging tasks for the plastic surgeon. Advances in wound management and microsurgical techniques in conjunction with long-term outcomes studies have expanded possibilities for limb salvage, but many aspects of management have continued to rely on principles set forth by Gustilo and Godina in the 1980s. The purpose of this article is to provide a comprehensive update on the various management aspects of traumatic lower extremity microvascular reconstruction based on the latest evidence, with an examination of recent publications.

Do Corporate Payments Influence Research Related to the Use of Acellular Dermal Matrices in Breast Surgery?

BACKGROUND: No study has assessed the impact of financial conflicts of interests (COIs) on the reporting of breast reconstruction outcomes with acellular dermal matrix (ADM) in peer-reviewed publications. The authors hypothesized that there is (1) an association between financial COIs and likelihood of studies reporting benefits in using ADM, and (2) inconsistent reporting of financial COIs. METHODS: The PubMed database was used to identify articles that reported on the use of ADM in breast surgery in four leading plastic surgery journals from January of 2014 to December of 2019. Financial COIs for authors were determined using the open payments database. RESULTS: Fifty-five articles were included. Twenty-four articles (43.6%) supported use of ADM, 12 (21.8%) did not promote ADM use, and 19 (34.5%) were neutral. Fifty-one studies (92.7%) had either a first or senior author with a COI, and authors with a COI more commonly reported positive outcomes ( P = 0.02). Studies with positive outcomes featured first authors who received significantly larger financial payments ($95,955 versus $15,642; P = 0.029) compared with studies with negative or neutral outcomes. Receiver operating characteristic curve demonstrated that studies with first authors receiving over $376.28 were more likely to report positive results. Eight senior authors and three first authors received greater than $500 from ADM producers yet did not report any financial disclosure. CONCLUSIONS: Financial COI is associated with higher likelihood of studies reporting benefit of using ADM in breast surgery. There remains inconsistent reporting of COIs, and better oversight is needed to ensure unbiased publication on the use of ADM in breast surgery.

Sensory Outcomes for Inferior Alveolar Nerve Reconstruction with Allograft following Free Fibula Mandible Reconstruction.

BACKGROUND: As patient survival with head and neck cancer has improved, treatment goals have had to evolve to focus on improving quality of life. Traditionally, patients who have undergone mandibulectomy are left with an insensate chin and lower lip secondary to resection of the inferior alveolar nerve (IAN). The purpose of this study was to critically evaluate the authors' initial experience using processed nerve allografts (PNA) for IAN reconstruction following oncologic mandibulectomy and reconstruction with free fibula osteocutaneous flaps and to assess their patients' sensory outcomes. METHODS: The authors performed a retrospective review of the first 32 patients who underwent immediate IAN reconstruction with PNA at the time of oncologic mandibulectomy and mandible reconstruction with free fibula osteocutaneous flaps at The University of Texas M. D. Anderson Cancer Center over a 1-year period. Semmes-Weinstein filament sensory testing was conducted at multiple surgical follow-up appointments to evaluate the quality of sensory recovery. RESULTS: Thirteen of the 32 patients underwent postoperative Semmes-Weinstein filament testing. All 13 patients demonstrated partial return of sensation. At a mean follow-up of 8.33 months, the average level of sensation was 60.93% that of the unaffected side of the lower lip. CONCLUSIONS: Patients were consistently afforded improvement in lower lip sensation using PNA-based IAN grafting as an adjunct to free fibula-based mandible reconstruction. The procedure adds no additional surgical morbidity and has shown consistent positive results.

The Medial Femoral Condyle Flap: A Novel Versatile Tool for Complex Microvascular Maxillofacial Reconstruction.

SUMMARY: The medial femoral condyle flap is well-described for reconstruction of small bone defects of the upper and lower extremities. There are limited case reports of its use in other anatomic sites, particularly for reconstruction of complex head and neck defects. In the setting of previous radiation and contaminated fields, vascularized bone is generally preferred to bone grafts, cadaveric allografts, or synthetic implants. The authors present a case series of complex craniofacial defects involving the midface that were reconstructed using medial femoral condyle flaps, focusing on the type of defect and lessons learned from their early experience to promote awareness of this flap among microsurgeons, who may wish to consider the potential of this flap and incorporate its use into their armamentarium. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Core outcome measures for clinical effectiveness trials of nutritional and metabolic interventions in critical illness: an international modified Delphi consensus study evaluation (CONCISE).

BACKGROUND: Clinical research on nutritional and metabolic interventions in critically ill patients is heterogenous regarding time points, outcomes and measurement instruments used, impeding intervention development and data syntheses, and ultimately worsening clinical outcomes. We aimed to identify and develop a set of core outcome domains and associated measurement instruments to include in all research in critically ill patients. METHODS: An updated systematic review informed a two-stage modified Delphi consensus process (domains followed by instruments). Measurement instruments for domains considered 'essential' were taken through the second stage of the Delphi and a subsequent consensus meeting. RESULTS: In total, 213 participants (41 patients/caregivers, 50 clinical researchers and 122 healthcare professionals) from 24 countries contributed. Consensus was reached on time points (30 and 90 days post-randomisation). Three domains were considered 'essential' at 30 days (survival, physical function and Infection) and five at 90 days (survival, physical function, activities of daily living, nutritional status and muscle/nerve function). Core 'essential' measurement instruments reached consensus for survival and activities of daily living, and 'recommended' measurement instruments for physical function, nutritional status and muscle/nerve function. No consensus was reached for a measurement instrument for Infection. Four further domains met criteria for 'recommended,' but not 'essential,' to measure at 30 days post-randomisation (organ dysfunction, muscle/nerve function, nutritional status and wound healing) and three at 90 days (frailty, body composition and organ dysfunction). CONCLUSION: The CONCISE core outcome set is an internationally agreed minimum set of outcomes for use at 30 and 90 days post-randomisation, in nutritional and metabolic clinical research in critically ill adults.

Patient-Centred Outcomes Following Open Carpal Tunnel Release: A Systematic Review of the Current Literature.

Background: Patients' individual interpretations of their own health outcomes are becoming increasingly important metrics in defining clinical success across all specialties, especially in hand surgery. However, there is a relative paucity of data using validated health-related quality of life (HR-QoL) assessments for carpal tunnel release (CTR). The purpose of this study was to review published outcomes on traditional open CTR to formally assess the current need for more accurate, validated assessment tools to evaluate CTR-specific HR-QoL. Methods: PubMed, MEDLINE and Cochrane Library databases were queried according to PRISMA guidelines for all studies investigating patient-reported outcomes following traditional open CTR. Analysis focused on HR-QoL, symptomatic relief, functional status, overall satisfaction and return to work or activities of daily living (ADLs). Results: In total, 588 unique articles were screened, and 30 studies met selection criteria. HR-QoL was formally assessed in only 3 studies using the validated 36-Item Short Form Survey. Symptomatic relief was measured in 29 (97%) studies, making it the most frequently reported item, whereas functional ability was reported by 19 (63%) studies. The Boston Carpal Tunnel Questionnaire was the most frequently utilised tool to assess symptomatic relief (13/30) and functional improvement (11/30). Using unvalidated custom surveys, 14 studies (47%) reported patient satisfaction and 12 studies (40%) documented time to return to work/ADLs. Conclusion: There is a dearth of studies utilising HR-QoL assessment tools to evaluate outcomes following traditional open CTR. The creation and validation of new CTR-specific HR-QoL tools accounting for both physical and psychological health is warranted. Level of Evidence: Level II (Therapeutic).

Acinetobacter quorum sensing contributes to inflammation-induced inhibition of orthopaedic implant osseointegration.

Implant infection impairs osseointegration of orthopaedic implants by inducing inflammation. Acinetobacter spp. are increasingly prevalent multi-drug resistant bacteria that can cause osteomyelitis. Acinetobacter spp. can also cause inflammation and thereby inhibit osseointegration in mice. The purpose of the present study was to investigate the role of quorum sensing in this context. Therefore, wild-type bacteria were compared with an isogenic abaI mutant defective in quorum sensing in a murine osseointegration model. The abaI quorum- sensing mutant affected significantly less osseointegration and interleukin (IL) 1ß levels, without detectably altering other pro-inflammatory cytokines. Wild-type bacteria had fewer effects on IL1 receptor (IL1R)-/- mice. These results indicated that quorum sensing in Acinetobacter spp. contributed to IL1ß induction and the resultant inhibition of osseointegration in mice. Moreover, targeting the Gram-negative acyl-homoserine lactone quorum sensing may be particularly effective for patients with Acinetobacter spp. infections.

Current Concepts in Maxillary Reconstruction.

SUMMARY: Defects involving the midface and maxilla pose unique challenges to reconstructive surgeons. The maxilla serves as the central keystone of the face and interfaces with various other facial subunits to affect form and function. Reconstructive methods range from prosthetics to free tissue transfer, and the indications for different options are reviewed here. Finally, special considerations including management of the orbit, dental rehabilitation, and future directions are discussed.

Comparing Donor Site Morbidity for Autologous Breast Reconstruction: Thigh vs. Abdomen.

Although abdominally-based free flaps have long been the gold standard, the profunda artery perforator (PAP) flap has emerged as an important alternative option for autologous breast reconstruction. The aim of this study was to directly compare the donor site morbidity of using the PAP versus deep inferior epigastric perforator (DIEP) free flap. Methods: We performed a retrospective review of patients undergoing autologous breast reconstruction using a DIEP and/or PAP flap from January 2017 to December 2020. In total, 30 PAP flap patients were matched with 60 DIEP flap patients. Outcomes included donor site wound dehiscence, length of stay, narcotic consumption, and pain scores. Patient-reported outcomes for the thigh versus abdomen were compared using questions derived from the BREAST-Q. Results: There was no significant difference in length of stay (P = 0.182), reoperation rates (P = 0.999), flap failure rates (P = 0.999), or donor site complications (P = 0.999). Both groups had similar mean pain scores, maximum pain scores, daily and total narcotic requirements. In comparing the thigh or abdomen as a donor site, there was no difference in frequency of negative symptoms (difficulty with daily activities, discomfort, tightness, and negative impact on ability to work) or satisfaction scores as related to their appearance in and out of clothing and the appearance of the scar. Conclusions: The thigh and abdomen are both suitable donor sites for autologous breast reconstruction with similar flap-related and patient-reported outcomes. The ultimate decision regarding whether to use a PAP or DIEP flap for breast reconstruction should be tailored based on patient anatomy and preference.

Identification and characterization of bisbenzimide compounds that inhibit human cytomegalovirus replication.

The shortcomings of current anti-human cytomegalovirus (HCMV) drugs has stimulated a search for anti-HCMV compounds with novel targets. We screened collections of bioactive compounds and identified a range of compounds with the potential to inhibit HCMV replication. Of these compounds, we selected bisbenzimide compound RO-90-7501 for further study. We generated analogues of RO-90-7501 and found that one compound, MRT00210423, had increased anti-HCMV activity compared to RO-90-7501. Using a combination of compound analogues, microscopy and biochemical assays we found RO-90-7501 and MRT00210423 interacted with DNA. In single molecule microscopy experiments we found RO-90-7501, but not MRT00210423, was able to compact DNA, suggesting that compaction of DNA was non-obligatory for anti-HCMV effects. Using bioinformatics analysis, we found that there were many putative bisbenzimide binding sites in the HCMV DNA genome. However, using western blotting, quantitative PCR and electron microscopy, we found that at a concentration able to inhibit HCMV replication our compounds had little or no effect on production of certain HCMV proteins or DNA synthesis, but did have a notable inhibitory effect on HCMV capsid production. We reasoned that these effects may have involved binding of our compounds to the HCMV genome and/or host cell chromatin. Therefore, our data expand our understanding of compounds with anti-HCMV activity and suggest targeting of DNA with bisbenzimide compounds may be a useful anti-HCMV strategy.

Dangle Protocols in Lower Extremity Reconstruction.

INTRODUCTION: Dangling protocols are known to vary by surgeon and center, and their specific regimen is often largely based on single surgeon or institutional experience. A systematic review was conducted to derive evidence-based recommendations for dangling protocols according to patient-specific and flap-specific considerations. METHODS: A systematic review was performed using PubMed, Embase-OVID and Cochrane-CENTRAL. Study design, patient and flap characteristics, protocol details, dangling-related complications, and flap success rate were recorded. Studies were graded using the Oxford Center for Evidence-Based Medicine Levels of Evidence Scale. Data heterogeneity precluded quantitative analysis. RESULTS: Eleven articles were included (level of evidence (range):IIb-IV; N (range):8-150; age (range):6-89). Dangling initiation, time, and frequency varied considerably. Flap success rate ranged from 94 to 100%. Active smoking, diabetes, and hypertension are associated with characteristic physiologic changes that require vigilance and potential protocol modification. Early dangling appears to be safe across a variety of free flap locations, sizes, and indications. Axial fasciocutaneous flaps may tolerate more aggressive protocols than muscular flaps. While flaps with single venous anastomosis tolerate dangling, double venous or flow-through anastomoses may provide additional benefit. Major limitations included small sample sizes, uncontrolled study designs, and heterogeneous patient selection, dangling practices, monitoring methods, and outcome measures. CONCLUSIONS: Significant heterogeneity persists in postoperative dangling protocols after lower extremity microvascular reconstruction. Patient comorbidities and flap characteristics appear to affect tolerance to dangling. We propose two different standardized pathways based on risk factors. Clinical vigilance should be exercised in tailoring lower extremity protocols to patients' individual characteristics and postoperative course.