Lower Extremity Reconstruction with Anterolateral Thigh Free-Flap Anastomoses: A Computational Fluid Dynamic Analysis.

BACKGROUND: The anterolateral thigh free flap is an option for repairing soft tissue defects of the distal lower extremity. This flap uses the descending branch of the lateral circumflex femoral (LCF) artery as the flap vessel. The recipient vessel in these flaps is often the anterior tibial (AT), posterior tibial (PT), or peroneal (P) arteries. Computational fluid dynamic (CFD) evaluation of anastomoses between these vessels can optimize outcomes. METHODS: Thirty-eight CFD models were created to model end-to-side (ETS) and end-to-end (ETE) anastomoses for lower extremity reconstruction. Seven out of thirty-eight models represented ETS anastomoses between the LCF and AT arteries with varying anastomotic angles. Nine out of thirty-eight models represented 45-degree ETS anastomoses between varying diameters of the LCF and AT, PT, and P arteries. Nine out of thirty-eight models represented stenosis on the flap vessel and recipient vessel, pre- and post-bifurcation. Nine out of thirty-eight models represented ETE anastomoses, rather than ETS, with varying vessel diameters. Four out of thirty-eight models represented ETE anastomoses with varying regions and levels of stenosis. RESULTS: Stasis of blood flow in ETS models increased as anastomotic angle increased in a logarithmic relationship (R 2 = 0.918). Flow was optimized overall as flap and recipient vessel diameters approached one another. In ETS models, flap vessel and postbifurcation recipient vessel stenosis were found to substantially increase stasis. CONCLUSION: Selection of flap and recipient vessels with similar diameters can optimize outcomes in microvascular anastomoses. In the context of lower extremity reconstruction with the ALT flap, the PT artery can be recommended as a first-line recipient vessel due to its similar vessel caliber to the LCF and relative ease of surgical access compared with the P artery. Avoidance of areas of stenosis is recommended to ensure laminar flow and reduce the operative difficulty associated with performing anastomoses on nonpliable arteries. Striving for increased acuity of anastomotic angles is recommended to optimize the flow in ETS microvascular anastomoses.

Cervical Necrotizing Fasciitis: A Severe Sequela of Open Mandibular Fracture and Delay in Treatment.

Cervical necrotizing fasciitis (CNF) is a rare condition in the United States, with very few cases reported as a sequela of mandibular fracture. The authors describe the case of a 40-year-old man with poor oral health and no significant past medical history who developed CNF following delayed treatment of an open mandibular fracture, leading to life-threatening septic shock, thrombophlebitis of the internal jugular vein, and septic emboli to the lungs. Successful management of this patient was accomplished by serial surgical debridement, the administration of broad-spectrum antibiotics, and hemodynamic support. Eventual reconstruction was performed with external fixation of the mandible fracture and split-thickness skin grafting for the left neck and chest wound. The authors recommend early treatment of open mandibular fractures for immunocompromised patients or patients with poor oral hygiene to avoid the rare but potentially fatal complication of CNF and highlight external fixation as a useful technique in select cases of complex mandibular fractures.

Cognitive dysfunction and increased phosphorylated tau are associated with reduced O-GlcNAc signaling in an aging mouse model of metabolic syndrome.

Metabolic syndrome (MetS), characterized by hyperglycemia, obesity, and hyperlipidemia, can increase the risk of developing late-onset dementia. Recent studies in patients and mouse models suggest a putative link between hyperphosphorylated tau, a component of Alzheimer's disease-related dementia (ADRD) pathology, and cerebral glucose hypometabolism. Impaired glucose metabolism reduces glucose flux through the hexosamine metabolic pathway triggering attenuated O-linked N-acetylglucosamine (O-GlcNAc) protein modification. The goal of the current study was to investigate the link between cognitive function, tau pathology, and O-GlcNAc signaling in an aging mouse model of MetS, agouti KKAy+/- . Male and female C57BL/6, non-agouti KKAy-/- , and agouti KKAy+/- mice were aged 12-18 months on standard chow diet. Body weight, blood glucose, total cholesterol, and triglyceride were measured to confirm the MetS phenotype. Cognition, sensorimotor function, and emotional reactivity were assessed for each genotype followed by plasma and brain tissue collection for biochemical and molecular analyses. Body weight, blood glucose, total cholesterol, and triglyceride levels were significantly elevated in agouti KKAy+/- mice versus C57BL/6 controls and non-agouti KKAy-/- . Behaviorally, agouti KKAy+/- revealed impairments in sensorimotor and cognitive function versus age-matched C57BL/6 and non-agouti KKAy-/- mice. Immunoblotting demonstrated increased phosphorylated tau accompanied with reduced O-GlcNAc protein expression in hippocampal-associated dorsal midbrain of female agouti KKAy+/- versus C57BL/6 control mice. Together, these data demonstrate that impaired cognitive function and AD-related pathology are associated with reduced O-GlcNAc signaling in aging MetS KKAy+/- mice. Overall, our study suggests that interaction of tau pathology with O-GlcNAc signaling may contribute to MetS-induced cognitive dysfunction in aging.

Trends in Integrated Plastic Surgery Applicant, Resident, and Junior Attending Research Productivity.

INTRODUCTION: Research productivity is critical for matching into integrated plastic surgery residency. This study will identify how pre and intraresidency research productivity correlate with resident/junior attending productivity. MATERIALS AND METHODS: Retrospective review from 2006 to 2015 issues of the American Board of Plastic Surgery's Annual Newsletter to Diplomates was performed to identify newly board certified plastic surgeons. Only surgeons from US medical schools matching directly into integrated programs were included. Residency type/length, graduation year from medical school, and publication counts were recorded for each surgeon. Publications were categorized as preresidency, intraresidency, and junior attending (6 y post residency/fellowship training). RESULTS: Six hundred fifty-five integrated plastic surgery graduates were analyzed. The median number of total publications (preresidency, intraresidency, and junior attending) was 4 (interquartile range [IQR], 1 to 10). Linear regression revealed negligible correlation between preresidency and junior attending publications (r = 0.019, P = 0.002). Total publications and increasing graduation y had a significant correlation of 0.89 (P < 0.001). Graduates of fellowships had significantly increased median total publications compared to those without fellowships (7 IQR, 3 to 18 versus 3 IQR, 1 to 7, respectively, P < 0.001). Dedicated research years during residency were associated with significant (P < 0.001) increases in median total and junior attending publications. Total publications ranged from 3 (IQR, 1 to 6) to 8 (IQR, 7 to 18) for those who completed 5- and 8-y residencies, respectively. CONCLUSIONS: Increased preresidency research productivity is not strongly associated with increased junior attending productivity in integrated plastic surgery. Better markers are completing dedicated research years in residency or fellowship after residency.