Systematic Review of Prophylactic Plastic Surgery Closure to Prevent Postoperative Wound Complications Following Spine Surgery.

Spinal surgeries are increasingly performed in the United States, but complication rates can be unacceptably high at up to 26%. Consequently, plastic surgeons (PS) are sometimes recruited by spine surgeons (SS) for intraoperative assistance with soft tissue closures. An electronic multidatabase literature search was systematically conducted to determine whether spinal wound closure performed by PS minimizes postoperative wound healing complications when compared to closure by SS (neurosurgical or orthopedic), with the hypothesis that closures by PS minimizes incidence of complications. All published studies involving patients who underwent posterior spinal surgery with closure by PS or SS at index spine surgery were identified. Filtering by exclusion criteria identified 10 studies, 4 of which were comparative in nature and included both closures by PS and SS. Of these 4, none reported significant differences in postoperative outcomes between the groups. Across all studies, PS were involved in cases with higher baseline risk for wound complications and greater comorbidity burden. Closures by PS were significantly more likely to have had prior chemotherapy in 2 of the 4 (50%) studies (P = 0.014, P < 0.001) and radiation in 3 of the 4 (75%) studies (P < 0.001, P < 0.01, P < 0.001). In conclusion, closures by PS are frequently performed in higher risk cases, and use of PS in these closures may normalize the risk of wound complications to that of the normal risk cohort, though the overall level of evidence of the published literature is low.

Article Factors Influencing Gender Disparities in Senior Authorship of Plastic Surgery Publications.

INTRODUCTION: Female plastic surgeons publish fewer and lower impact articles. To better understand how to address this gender gap, we explored the temporal trends in female senior authorship and evaluated predictive factors for female senior authorship. METHODS: A retrospective review of articles published in the 3 highest impact plastic surgery journals published from 2010 to 2020 was conducted. Trends with female senior authorship across time were analyzed with respect to study type, subspeciality, and geographical origin. RESULTS: Of the 5425 articles included, 13% (n = 720) had a female senior author, and female senior authorship increased across time ( R = 0.84, P = 0.033). Over the decade, an increased proportion of cohort studies ( R = 0.82, P = 0.045), systematic reviews ( R = 0.96, P = 0.003), breast-related articles ( R = 0.88, P = 0.022), and reconstruction-related articles ( R = 0.83, P = 0.039) were published by female senior authors. Subspecialty and geography predicted female senior authorship; articles focused on aesthetic (odds ratio [OR] = 1.3, P = 0.046) and breast (OR = 1.7, P < 0.001) subspecialties or those originating from Canada (OR = 1.7 P = 0.019), Europe (OR = 1.5, P < 0.001), and Latin America (OR = 3.0, P < 0.001) were more likely to have a female senior author. Articles from East Asia were less likely to have female senior authors (OR = 0.7, P = 0.005). CONCLUSION: Female senior authorship in plastic surgery has increased over the last decade, and the proportion of female plastic surgeons leading cohort studies and systematic reviews is increasing. Sex of the senior author is influenced by plastic surgery subspecialty and geographical origin, but article type did not impact the odds of female senior authorship.

A Cost-effective, 3D Printed Simulation Model Facilitates Learning of Bilobed and Banner Flaps for Mohs Nasal Reconstruction: A Pilot Study.

SUMMARY: Flap design for Mohs reconstruction is a complex 3-dimensional decision-making process. Simulation offers trainees the chance to practice techniques safely, prior to opportunities in the operating room. To aide in teaching, we developed a high-fidelity, cost-effective model of the face using three-dimensional (3D) printing to simulate flap reconstruction following Mohs surgery. We describe the design of this model and its impact on the comfort and proficiency of trainees.

Allometrically scaling tissue forces drive pathological foreign-body responses to implants via Rac2-activated myeloid cells.

Small animals do not replicate the severity of the human foreign-body response (FBR) to implants. Here we show that the FBR can be driven by forces generated at the implant surface that, owing to allometric scaling, increase exponentially with body size. We found that the human FBR is mediated by immune-cell-specific RAC2 mechanotransduction signalling, independently of the chemistry and mechanical properties of the implant, and that a pathological FBR that is human-like at the molecular, cellular and tissue levels can be induced in mice via the application of human-tissue-scale forces through a vibrating silicone implant. FBRs to such elevated extrinsic forces in the mice were also mediated by the activation of Rac2 signalling in a subpopulation of mechanoresponsive myeloid cells, which could be substantially reduced via the pharmacological or genetic inhibition of Rac2. Our findings provide an explanation for the stark differences in FBRs observed in small animals and humans, and have implications for the design and safety of implantable devices.

Outcome measures reported following feminizing genital gender affirmation surgery for transgender women and gender diverse individuals: A systematic review.

Background: Feminizing genital gender affirmation surgery (fgGAS) may be an essential adjunct in the care of some transgender women and gender diverse individuals with gender incongruence. However, the comparison of different techniques of fgGAS may be confounded by variable outcome reporting and the use of inconsistent outcomes in the literature. This systematic review provides the most in-depth examination of fgGAS studies to date, and summarizes all reported outcomes, definitions, and the times when outcomes were assessed following these surgical interventions. Aims/Methods: This work intends to quantify the levels of outcome variability and definition heterogeneity in this expanding field and provides guidance on outcome reporting for future study authors. Candidate studies for this systematic review were sourced via an electronic, multi-database literature search. All primary, clinical research studies of fgGAS were included with no date limits. Paired collaborators screened each study for inclusion and performed data extraction to document the outcomes, definitions, and times of outcome assessment following fgGAS. Results: After screening 1225 studies, 93 studies proceeded to data extraction, representing 7681 patients. 2621 separate individual outcomes were reported, 857 (32.7%) were defined, and the time of outcome assessment was given for 1856 outcomes (70.8%) but relied on nonspecific ranges of follow-up dates. "Attainment of orgasm", "Neovaginal stenosis", and "Neovaginal depth/length" were among the most commonly reported outcomes. Profound heterogeneity existed in the definitions used for these and for all outcomes reported in general. Discussion: The results demonstrate a need for clear outcomes, agreed definitions, and times of outcome assessment following fgGAS in transgender women and gender diverse individuals. The adoption of a consistent set of outcomes and definitions reported by all future studies of fgGAS (a Core Outcome Set) will aid in improving treatment comparisons in this patient group. This review is the first step in that process.

A Systematic Review and Meta-Analysis Comparing the Clinical Outcomes of Profunda Artery Perforator Versus Gracilis Thigh Flap as a Second Choice for Autologous Breast Reconstruction.

PURPOSE: Autologous breast reconstruction remains a versatile option to produce a natural appearing breast after mastectomy. The deep inferior epigastric perforator remains the most commonly used flap choice, but when this donor site is unsuitable or unavailable, the transverse upper gracilis (TUG) or profunda artery perforator (PAP) flaps are popular secondary alternatives. We conduct a meta-analysis to better understand patient outcomes and adverse events in secondary flap selection in breast reconstruction. METHODS: A systematic search was conducted on MEDLINE and Embase for all articles published on TUG and/or PAP flaps for oncological breast reconstruction in postmastectomy patients. A proportional meta-analysis was conducted to statistically compare outcomes between PAP and TUG flaps. RESULTS: The TUG and PAP flaps were noted to have similar reported rates of success and incidences of hematoma, flap loss, and flap healing (P > 0.05). The TUG flap was noted to have significantly more vascular complications (venous thrombosis, venous congestion, and arterial thrombosis) than the PAP flap (5.0% vs 0.6%, P < 0.01) and significantly greater rates of unplanned reoperations in the acute postoperative period (4.4% vs 1.8%, P = 0.04). Infection, seroma, fat necrosis, donor healing complications, and rates of additional procedures all exhibited high degree of heterogeneity precluding mathematical synthesis of outcomes across studies. CONCLUSIONS: Compared with TUG flaps, PAP flaps have fewer vascular complications and fewer unplanned reoperations in the acute postoperative period. There is need for greater homogeneity in reported outcomes between studies to enable for synthesis of other variables important in determining flap success.

A Combination of Distinct Vascular Stem/Progenitor Cells for Neovascularization and Ischemic Rescue.

BACKGROUND: Peripheral vascular disease remains a leading cause of vascular morbidity and mortality worldwide despite advances in medical and surgical therapy. Besides traditional approaches, which can only restore blood flow to native arteries, an alternative approach is to enhance the growth of new vessels, thereby facilitating the physiological response to ischemia. METHODS: The ActinCreER/R26VT2/GK3 Rainbow reporter mouse was used for unbiased in vivo survey of injury-responsive vasculogenic clonal formation. Prospective isolation and transplantation were used to determine vessel-forming capacity of different populations. Single-cell RNA-sequencing was used to characterize distinct vessel-forming populations and their interactions. RESULTS: Two populations of distinct vascular stem/progenitor cells (VSPCs) were identified from adipose-derived mesenchymal stromal cells: VSPC1 is CD45-Ter119-Tie2+PDGFRa-CD31+CD105highSca1low, which gives rise to stunted vessels (incomplete tubular structures) in a transplant setting, and VSPC2 which is CD45-Ter119-Tie2+PDGFRa+CD31-CD105lowSca1high and forms stunted vessels and fat. Interestingly, cotransplantation of VSPC1 and VSPC2 is required to form functional vessels that improve perfusion in the mouse hindlimb ischemia model. Similarly, VSPC1 and VSPC2 populations isolated from human adipose tissue could rescue the ischemic condition in mice. CONCLUSIONS: These findings suggest that autologous cotransplantation of synergistic VSPCs from nonessential adipose tissue can promote neovascularization and represents a promising treatment for ischemic disease.

Taming the Tongue: The Surgical Approach to Macroglossia.

While traditionally in the realm of otorhinolaryngology or oral maxillofacial surgery, conditions involving the tongue may also be managed by plastic surgeons. The authors present an unusual case of acquired macroglossia resulting from angiotensin-converting enzyme inhibitor-induced angioedema and review the literature to discuss its surgical management from a plastic surgery perspective. A 62-year-old female suffered severe airway obstruction, respiratory arrest, and anoxic brain injury from angioedema-associated macroglossia. After tracheostomy, the patient was managed nonsurgically, with bite wound care and medications to minimize angioedema to marginal effect. Ultimately, a partial glossectomy was planned. The edematous distal tongue was amputated and closed primarily. On postoperative day 2, she was successfully weaned off mechanical ventilation and no longer suffers trauma from tongue biting. The simple anterior tongue resection described in this paper was an appropriate approach for our patient. More research is needed to guide plastic surgeons in an optimal approach for clinical scenarios.

Evaluation of Xenograft Efficacy in Immediate Prosthesis-based Breast Reconstruction.

The advent of acellular dermal matrix (ADM) has revolutionized prosthesis-based breast reconstruction. However, paucity of human cadaveric tissue has resulted in limitation of supply and increased associated costs, prompting concerted effort to identify xenograft alternatives. Although studies have examined the safety of Artia, a porcine-derived ADM, few have evaluated its clinical efficacy as soft tissue reinforcement. This study uniquely evaluates the clinical efficacy of Artia in implant-based breast reconstruction. Methods: IRB-approved retrospective chart review was conducted to identify 243 consecutive TE-based procedures performed at a tertiary academic medical center between March 2017 and March 2021. Propensity matching was conducted to minimize differences between cohorts. Efficacy metrics, defined as initial tissue expander (TE) fill volume, number of TE fills, and time interval between exchange of TE for final implant, were compared between xenograft (Artia) and allograft (AlloDerm) groups. Results: Patients who underwent Artia-based breast reconstruction achieved superior initial TE fill volume relative to those who underwent AlloDerm-based breast reconstruction via univariate analysis (317.3 ± 185.8 mL versus 286.1 ± 140.4 mL, P < 0.01) when patient and operative characteristics were well-matched. However, linear regression analysis failed to demonstrate difference in efficacy metrics, such as initial TE fill volume (P = 0.31), ratio between initial TE fill volume and final implant size (P = 0.19), and number of TE fills (P = 0.76). Complication rates were comparable between groups. Conclusion: This study suggests that Artia can be used as a safe and efficacious alternative to human-derived ADM in immediate TE-based breast reconstruction.

Profibrotic Signaling Pathways and Surface Markers Are Up-Regulated in Fibroblasts of Human Striae Distensae and in a Mouse Model System.

BACKGROUND: Striae distensae are common disfiguring cutaneous lesions but lack effective treatments because of an incomplete understanding of their pathophysiology. Dermal fibroblasts likely play an important role. The authors investigate the cellular-molecular features distinguishing fibroblasts from human striae distensae and normal skin. The authors also develop a mouse model of striae distensae. METHODS: Human striae distensae and normal skin samples were compared for tensile strength and histologic structure. Fibroblasts from striae distensae and normal skin were isolated by fluorescence-activated cell sorting for gene expression analysis. Immunofluorescence staining and fluorescence-activated cell sorting were used to confirm gene expression data at the protein level. A mouse model of striae distensae formation was created by administering corticosteroids and mechanically loading the dorsal skin. RESULTS: Human striae distensae exhibited reduced tensile strength, more disordered collagen fibers, and epidermal atrophy compared to human normal skin. There were 296 up-regulated genes in striae distensae fibroblasts, including the profibrotic lineage and surface marker CD26. Up-regulated genes were involved in profibrotic and mechanoresponsive signaling pathways (TGFß and FAK-PI3-AKT-signaling). In contrast, 571 genes were down-regulated, including CD74 and genes of the AMPK pathway. Increased CD26 and decreased CD74 expression was confirmed by fluorescence-activated cell sorting and immunofluorescence. Similar cutaneous histologic and gene expression changes were induced in hypercortisolemic mice by mechanically loading the dorsal skin. CONCLUSIONS: Fibroblasts from human striae distensae exhibit increased profibrotic and decreased antifibrotic signaling. CD26 and CD74 are promising surface markers that may be targeted therapeutically. The authors' mouse model of striae distensae can be used as a platform to test the efficacy of potential therapeutic agents. CLINICAL RELEVANCE STATEMENT: Striae distensae are common disfiguring cutaneous lesions whose etiology remains elusive, which has hindered development of effective treatment strategies. Dermal fibroblasts likely play an important role. The authors sought to elucidate the key cellular-molecular pathways distinguishing fibroblasts in striae distensae from those in normal skin.

Smooth versus textured tissue expanders in breast reconstruction - A retrospective review of post-operative surgical site infections.

BACKGROUND: Textured tissue expanders (TTEs) were introduced to limit migration and reduce capsular contracture, which were inherent to smooth tissue expanders (STEs). Previous reports suggest that textured devices have increased rates of bacterial contamination and biofilm formation in comparison with smooth devices. Recently, the relative increased association of anaplastic large cell lymphoma (ALCL) with textured versus smooth devices has led to increased adoption of smooth devices. The aim of our study is to evaluate the post-operative surgical site infection (SSI) rates of STEs versus TTEs. METHODS: A retrospective case series was conducted at a single academic teaching hospital from April 2016 to December 2019. The primary outcome variable was the development of a post-operative SSI. RESULTS: One hundred seventy-seven breasts underwent reconstruction with TTEs and 109 breasts underwent reconstruction with STE. In total, 54 SSIs were recorded (n = 34 TTE; n = 20 STE), with the majority of infections occurring within the first 30 post-operative days (TTE 65%, STE 70%). There was no statistically significant difference in overall post-operative infection rates between TTE and STE groups when broken down into the following time points: <30 day, 30-60 days, and >90 days (p = 0.924). There was no statistically significant difference between infection type (superficial vs. deep, p = 0.932), infection management (medical, surgical, or both, p = 0.409) or salvage results (p = 0.078) seen in STE versus TTE cohort. On multivariate analysis, seroma history was associated with SSI development (OR 3.18, p = 0.041). CONCLUSION: There was no significant difference in the rate of post-operative SSI following breast reconstruction with STE relative to TTE.

Decellularized Adipose Matrices Can Alleviate Radiation-Induced Skin Fibrosis.

Objective: Radiation therapy is commonplace for cancer treatment but often results in fibrosis and atrophy of surrounding soft tissue. Decellularized adipose matrices (DAMs) have been reported to improve these soft tissue defects through the promotion of adipogenesis. These matrices are decellularized by a combination of physical, chemical, and enzymatic methods to minimize their immunologic effects while promoting their regenerative effects. In this study, we aimed at exploring the regenerative ability of a DAM (renuva®; MTF biologics, Edison, NJ) in radiation-induced soft tissue injury. Approach: Fresh human lipoaspirate or DAM was injected into the irradiated scalp of CD-1 nude mice, and volume retention was monitored radiographically over 8 weeks. Explanted grafts were histologically assessed, and overlying skin was examined histologically and biomechanically. Irradiated human skin was also evaluated from patients after fat grafting or DAM injection. However, integrating data between murine and human skin in all cohorts is limited given the genetic variability between the two species. Results: Volume retention was found to be greater with fat grafts, though DAM retention was, nonetheless, appreciated at irradiated sites. Improvement in both mouse and human irradiated skin overlying fat and DAM grafts was observed in terms of biomechanical stiffness, dermal thickness, collagen density, collagen fiber networks, and skin vascularity. Innovation: This is the first demonstration of the use of DAMs for augmenting the regenerative potential of irradiated mouse and human skin. Conclusions: These findings support the use of DAMs to address soft tissue atrophy after radiation therapy. Morphological characteristics of the irradiated skin can also be improved with DAM grafting.

A Novel Xenograft Model Demonstrates Human Fibroblast Behavior During Skin Wound Repair and Fibrosis.

Objective: Xenografts of human skin in immunodeficient mice provide a means of assessing human skin physiology and its response to wounding. Approach: We describe a novel xenograft model using full-thickness human neonatal foreskin to examine human skin wound repair. Full-thickness 8 mm human neonatal foreskin biopsies were sutured into the dorsum of NOD scid gamma (NSG; NOD.Cg-Prkdc scidIl2rgtm1Wjl/SzJ) pups as subcutaneous grafts. At postnatal day 21 the subcutaneous grafts were exposed to cutaneous grafts. Following maturation of 2 months, xenografts were then wounded with 5 mm linear incisions and monitored until postwound day (PWD) 14 to study skin repair and fibrosis. To explore whether our model can be used to test the efficacy of topical therapies, wounded xenografts were injected with antifibrotic fibroblast growth factor 2 (FGF2) for the first four consecutive PWDs. Xenografts were harvested for analysis by histology and fluorescence-activated cell sorting (FACS). Results: Xenografts were successfully engrafted with evidence of mouse-human anastomoses and resembled native neonatal foreskin at the gross and microscopic level. Wounded xenografted skin scarred with human collagen and an expansion of CD26-positive human fibroblasts. Collagen scar was quantitated by neural network analysis, which revealed distinct clustering of collagen fiber networks from unwounded skin and wounded skin at PWD7 and PWD14. Collagen fiber networks within FGF2-treated wounds at PWD14 resembled those in untreated wounded xenografts at PWD7, suggesting that FGF2 treatment at time of wounding can reduce fibrosis. Innovation and Conclusion: This novel xenograft model can be used to investigate acute fibrosis, fibroblast heterogeneity, and the efficacy of antifibrotic agents during wound repair in human skin.

Stevens-Johnson syndrome and toxic epidermal necrolysis: a systematic review and meta-analysis.

OBJECTIVE: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare and severe skin and mucosal reactions that are associated with high mortality. Despite the severity, an evidence-based treatment protocol for SJS/TEN is still lacking. METHOD: In this systematic review and meta-analysis, the PubMed database was searched using the following terms: [Stevens-Johnson syndrome] OR [toxic epidermal necrolysis] AND [therapy] OR [treatment] over a 20-year period (1999-2019) in the German and English language. All clinical studies reporting on the treatment of SJS/TEN were included, and epidemiological and diagnostic aspects of treatment were analysed. A meta-analysis was conducted on all comparative clinical studies that met the inclusion criteria. RESULTS: A total of 88 studies met the inclusion criteria, reporting outcomes in 2647 patients. Treatment was either supportive or used systemic corticosteroid, intravenous immunoglobulin, plasmapheresis, cyclosporine, thalidomide or cyclophosphamide therapy. The meta-analysis included 16 (18%) studies, reporting outcomes in 976 (37%) patients. Systemic glucocorticoids showed a survival benefit for SJS/TEN patients in all analyses compared with other forms of treatment. Cyclosporine treatment also showed promising results, despite being used in a small cohort of patients. No beneficial effects on mortality could be demonstrated for intravenous immunoglobulins. CONCLUSION: Glucocorticoids and cyclosporine may be tentatively recommended as the most promising immunomodulatory therapies for SJS/TEN, but these results should be investigated in future prospective controlled trials.

Disrupting biological sensors of force promotes tissue regeneration in large organisms.

Tissue repair and healing remain among the most complicated processes that occur during postnatal life. Humans and other large organisms heal by forming fibrotic scar tissue with diminished function, while smaller organisms respond with scarless tissue regeneration and functional restoration. Well-established scaling principles reveal that organism size exponentially correlates with peak tissue forces during movement, and evolutionary responses have compensated by strengthening organ-level mechanical properties. How these adaptations may affect tissue injury has not been previously examined in large animals and humans. Here, we show that blocking mechanotransduction signaling through the focal adhesion kinase pathway in large animals significantly accelerates wound healing and enhances regeneration of skin with secondary structures such as hair follicles. In human cells, we demonstrate that mechanical forces shift fibroblasts toward pro-fibrotic phenotypes driven by ERK-YAP activation, leading to myofibroblast differentiation and excessive collagen production. Disruption of mechanical signaling specifically abrogates these responses and instead promotes regenerative fibroblast clusters characterized by AKT-EGR1.

Angiogenic CD34+CD146+ adipose-derived stromal cells augment recovery of soft tissue after radiotherapy.

Radiation therapy is effective for cancer treatment but may also result in collateral soft tissue contracture, contour deformities, and non-healing wounds. Autologous fat transfer has been described to improve tissue architecture and function of radiation-induced fibrosis and these effects may be augmented by enrichment with specific adipose-derived stromal cells (ASCs) with enhanced angiogenic potential. CD34+CD146+, CD34+CD146-, or CD34+ unfractionated human ASCs were isolated by flow cytometry and used to supplement human lipoaspirate placed beneath the scalp of irradiated mice. Volume retention was followed radiographically and fat grafts as well as overlying soft tissue were harvested after eight weeks for histologic and biomechanical analyses. Radiographic evaluation revealed the highest volume retention in fat grafts supplemented with CD34+CD146+ ASCs, and these grafts were also found to have greater histologic integrity than other groups. Irradiated skin overlying CD34+CD146+ ASC-enriched grafts was significantly more vascularized than other treatment groups, had significantly less dermal thickness and collagen deposition, and the greatest improvement in fibrillin staining and return of elasticity. Radiation therapy obliterates vascularity and contributes to scarring and loss of tissue function. ASC-enrichment of fat grafts with CD34+CD146+ ASCs not only enhances fat graft vascularization and retention, but also significantly promotes improvement in overlying radiation-injured soft tissue. This regenerative effect on skin is highly promising for patients with impaired wound healing and deformities following radiotherapy.

JUN promotes hypertrophic skin scarring via CD36 in preclinical in vitro and in vivo models.

Pathologic skin scarring presents a vast economic and medical burden. Unfortunately, the molecular mechanisms underlying scar formation remain to be elucidated. We used a hypertrophic scarring (HTS) mouse model in which Jun is overexpressed globally or specifically in α-smooth muscle or collagen type I­expressing cells to cause excessive extracellular matrix deposition by skin fibroblasts in the skin after wounding. Jun overexpression triggered dermal fibrosis by modulating distinct fibroblast subpopulations within the wound, enhancing reticular fibroblast numbers, and decreasing lipofibroblasts. Analysis of human scars further revealed that JUN is highly expressed across the wide spectrum of scars, including HTS and keloids. CRISPR-Cas9­mediated JUN deletion in human HTS fibroblasts combined with epigenomic and transcriptomic analysis of both human and mouse HTS fibroblasts revealed that JUN initiates fibrosis by regulating CD36. Blocking CD36 with salvianolic acid B or CD36 knockout model counteracted JUN-mediated fibrosis efficacy in both human fibroblasts and mouse wounds. In summary, JUN is a critical regulator of pathological skin scarring, and targeting its downstream effector CD36 may represent a therapeutic strategy against scarring.