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The modern surgeon faces an ever-changing landscape of procedural innovation. The demands of present-day healthcare highlight the importance of successfully developing new medical devices and technologies. This effort requires multidisciplinary collaborations of professionals ranging from manufacturers and engineers to researchers and healthcare providers. Surgeons regularly interact with complex equipment and user interfaces without substantial formal education on their design and development. The objective of this study was to ascertain the impact of a 10-week BME course into a medical school curriculum on surgery-bound students' knowledge of product design and gauge their ability to develop an actual product to meet a real need in a surgical field.A Medical Device Design and Commercialization co-enrolled elective course was offered to medical students at a single institution. Five students with an expressed surgical and procedural interest were enrolled. At the beginning of the course, they were tasked with developing a product to meet a clinical need they observed. At the conclusion of the course, students filled out a questionnaire about their level of comfort and knowledge of the material using a 5-point Likert scale. This survey was administered to a control group of medical students who did not take the course.The BME student cohort was able to successfully identify a post-operative need, develop a prototype of a novel device, and present their product to attending surgeons. A total of 35 survey entries were received: five from the experimental group and 30 from the comparison group. The experimental group scored higher than the comparison group for all survey questions and reached the level of statistical significance in 13 of the 15 questions (p 0.05). Survey respondents reported similar degrees of knowledge and comfort in recognizing unmet needs in a hospital setting and formulating a comprehensive statement describing them.The principles of biomedical engineering are integral to advancing the field of surgery. Presently, a small cohort of medical students/residents successfully acquired and applied basic BME concepts in a relatively short period of time relative to other training paradigms. Our findings also suggest medical students recognize unmet needs in the hospital setting, and those who completed a BME course felt more able to take steps to meet those needs. Early integration of biomedical engineering principles in medical training may help produce more innovative and well-rounded surgeons.

Physical review / B 106(12), 125138 (2022). doi:10.1103/PhysRevB.106.125138, We report a high-resolution angle-resolved photoemission (ARPES) study of the prototypical nearly free-electron metal sodium. The observed mass enhancement is slightly smaller than that derived in previous studies. The new results on the lifetime broadening increase the demand for theories beyond the random phase approximation. Our results do not support the proposed strong enhancement of the scattering rates of the charge carriers due to a coupling to spin fluctuations. Moreover, a comparison with earlier electron energy-loss data on sodium yields a strong reduction of the mass enhancement of dipolar electron-hole excitations compared to that of monopole hole excitations, measured by ARPES., Published by Inst., Woodbury, NY

Dental zirconia is often marketed and selected for restorative use based upon the biaxial flexural strength of prefabricated specimens (disks) without considering other mechanical and physical properties.The purpose of this in vitro study was to test whether 4-point flexural strength, biaxial flexural strength, and/or hardness may correlate with failure loads for crowns made of different zirconia materials.Three brands of zirconia (BruxZir, Cercon, and Katana) were used to fabricate anatomically contoured crowns, rectangular bars, and circular disks. The sample size was n=15 specimens per zirconia brand and specimen shape. The bars were tested for 4-point flexural strength by using the 4-point bending (4PB) test and Vickers hardness (VH), while the disks were tested for biaxial flexural strength by using a piston-on-3 ball (POB) test. Crowns were attached to resin abutments and compressed with a steel spherical indenter through a polyethylene sheet to assess the failure loads by using the "crunch the crown" (CTC) test. One-way ANOVA (α=.05) was used to test for statistically significant differences between groups, and Weibull analysis was used to assess the variability of the measured flexural strengths, failure load, and hardness.Statistical differences (P.001) were found in comparing Cercon, BruxZir, and Katana ([4260 N=4186 N]3195 N, respectively) with the CTC test and (396 MPa[281 MPa=275 MPa], respectively) the 4PB test. No statistical differences (P=.084) were found among the zirconia brands (Cercon [384 MPa]=Bruxzir [359 MPa]=Katana [416 MPa]) for the POB test. No significant correlations (P.05) were found between the 4PB, POB, or VH tests and the corresponding CTC test. The Weibull modulus varied for the different specimen geometries.The piston-on-3 ball, 4-point bending, and Vickers hardness test results were not correlated with the corresponding crunch-the-crown test.

Asbestos-related mesotheliomas belong to the group of the most frequent occupational diseases in Germany, reaching about 1,000 new cases per year. The disease has a dismal prognosis because most tumors remain asymptomatic for a long time and therefore are diagnosed as incidental findings at later stages.During the last decade the German Social Accident Insurance (DGUV) has made considerable efforts to prepone the diagnosis in order to detect the disease at earliest possible stages. These efforts resulted in new findings showing that, in a high-risk group, a combination of the biomarkers calretinin and mesothelin was able to advance the diagnosis up to 12 months.Ideally, the diagnosis of a mesothelioma at an early stage has to be accompanied by the best possible individualized therapy. Standard therapeutic strategies are surgery and chemotherapy, added by radiotherapy and psycho-oncology. In recent years, several new therapeutic avenues are being explored. This review comprehensively presents both old and new therapeutic options in mesothelioma, based on international Leitlinien and new studies.Asbestverursachte maligne Mesotheliome gehören in Deutschland mit etwa 1000 jährlichen Neuerkrankungen zu den häufigen arbeitsbedingten Krebserkrankungen. Die Prognose ist oftmals schlecht, da die Erkrankung lange symptomlos bleibt und deshalb meist erst als Zufallsbefund in bereits fortgeschrittenen Stadien diagnostiziert wird.Die deutsche gesetzliche Unfallversicherung (DGUV) hat in den letzten Jahren erhebliche Anstrengungen unternommen, eine Vorverlagerung des Diagnosezeitpunkts zu erreichen, um die Erkrankung möglichst in Frühstadien zu detektieren. Die aus diesen Bestrebungen resultierenden neuen medizinisch-wissenschaftlichen Erkenntnisse zeigen, dass die Kombination der Biomarker Calretinin und Mesothelin in einer Hochrisikogruppe die Vorverlegung der Diagnose um bis zu 12 Monaten ermöglicht.Die Diagnose eines Mesothelioms im Frühstadium wird idealerweise von der individuell bestmöglichen Therapie gefolgt. Die Standardtherapie basiert auf operativer Entfernung des Tumors und Chemotherapie, ergänzt um Strahlentherapie und Psychoonkologie. In den letzten Jahren wurden einige neue Therapieansätze entwickelt. Die Übersicht stellt den aktuellen Stand der Therapie des Mesothelioms, basierend auf den internationalen Leitlinien und neuen Studien, dar.

In this paper, we introduce an improved, three-dimensional coplanar line structure manufactured using Laser Direct Structuring (LDS) technology. The low-loss and robust against tolerance transmission line structure can be used for building conformal millimeter wave (mmWave) sensor applications as e.g. automotive radar.

HistoryA 63-year-old woman with a history of left mastectomy for breast cancer and partial gastrectomy with Roux-en-Y reconstruction for nonhealing peptic ulcer presented to the emergency department and reported a 1-month history of abdominal distention, fevers, chills, and flu-like symptoms. She was initially suspected of having flu, and she completed a course of oseltamivir; however, she had continued fatigue, fever, chills, abdominal bloating, and loss of appetite. She reported no contact with a sick person or recent travel. At admission, laboratory studies revealed leukocytosis, with a white blood cell count of 15.1 × 10

HistoryA 63-year-old woman with a history of left mastectomy for breast cancer and partial gastrectomy with Roux-en-Y reconstruction for nonhealing peptic ulcer presented to the emergency department and reported a 1-month history of abdominal distention, fevers, chills, and flu-like symptoms. She was initially suspected of having flu, and she completed a course of oseltamivir; however, she had continued to experience fatigue, fever, chills, abdominal bloating, and loss of appetite. She reported no contact with a sick person or recent travel. At admission, laboratory studies revealed leukocytosis, with a white blood cell count of 15.1 × 103/μL (15.1 × 109/L) (normal range, 4.0-10.0 × 103/μL [4.0-10.0 × 109/L]), an elevated sedimentation rate of 100 mm per hour (normal range, 0-30 mm per hour), and a C-reactive protein level of 203.8 mg/L (1940.9 nmol/L) (normal range, ≤10 mg/L [≤95.2 nmol/L]). Liver enzyme levels were elevated, with an alanine aminotransferase level of 48 U/L (0.80 µkat/L) (normal range, 0-29 U/L [0-0.48 µkat/L]), an aspartate aminotransferase level of 98 U/L (1.6 µkat/L) (normal range, 10-37 U/L [0.16-0.62 µkat/L]), an alkaline phosphatase level of 682 U/L (11.4 μkat/L) (normal range, 65-195 U/L [1.1-3.3 μkat/L]), and a total bilirubin level of 1.5 mg/dL (25.7 µmol/L) (normal range, 0.3-1.0 mg/dL [5.1-17.1 μmol/L]). Abdominopelvic CT was performed.

Cardiac tissue surrogates show promise for restoring mechanical and electrical function in infarcted left ventricular (LV) myocardium. For these cardiac surrogates to be useful in vivo, they are required to support synchronous and forceful contraction over the infarcted region. These design requirements necessitate a thickness sufficient to produce a useful contractile force, an area large enough to cover an infarcted region, and prevascularization to overcome diffusion limitations. Attempts to meet these requirements have been hampered by diffusion limits of oxygen and nutrients (100–200 µm) leading to necrotic regions. This study demonstrates a novel layer-by-layer (LbL) fabrication method used to produce tissue surrogates that meet these requirements and mimic normal myocardium in form and function. Thick (1.5–2 mm) LbL cardiac tissues created from human induced pluripotent stem cell-derived cardiomyocytes and endothelial cells were assessed, in vitro, over a 4-week period for viability (R 2 < 0.98). Functional performance assessment showed enhanced t-tubule network development, gap junction communication as well as conduction velocity (16.9 ± 2.3 cm s−1). These results demonstrate that LbL fabrication can be utilized successfully in creating complex, functional cardiac surrogates for potential therapeutic applications.

Background There is substantial interest in electrospun scaffolds as substrates for tissue regeneration and repair due to their fibrous, extracellular matrix-like composition with interconnected porosity, cost-effective production, and scalability. However, a common limitation of these scaffolds is their inherently low mechanical strength and stiffness, restricting their use in some clinical applications. In this study we developed a novel technique for 3D printing a mesh reinforcement on electrospun scaffolds to improve their mechanical properties. Methods A poly (lactic acid) (PLA) mesh was 3D-printed directly onto electrospun scaffolds composed of a 40:60 ratio of poly(ε-caprolactone) (PCL) to gelatin, respectively. PLA grids were printed onto the electrospun scaffolds with either a 6 mm or 8 mm distance between the struts. Scanning electron microscopy was utilized to determine if the 3D printing process affected the archtitecture of the electrospun scaffold. Tensile testing was used to ascertain mechanical properties (strength, modulus, failure stress, ductility) of both unmodified and reinforced electrospun scaffolds. An in vivo bone graft model was used to assess biocompatibility. Specifically, reinforced scaffolds were used as a membrane cover for bone graft particles implanted into rat calvarial defects, and implant sites were examined histologically. Results We determined that the tensile strength and elastic modulus were markedly increased, and ductility reduced, by the addition of the PLA meshes to the electrospun scaffolds. Furthermore, the scaffolds maintained their matrix-like structure after being reinforced with the 3D printed PLA. There was no indication at the graft/tissue interface that the reinforced electrospun scaffolds elicited an immune or foreign body response upon implantation into rat cranial defects. Conclusion 3D-printed mesh reinforcements offer a new tool for enhancing the mechanical strength of electrospun scaffolds while preserving the advantageous extracellular matrix-like architecture. The modification of electrospun scaffolds with 3D-printed reinforcements is expected to expand the range of clinical applications for which electrospun materials may be suitable.

Introduction Historiquement, la survie des patients atteints de CBNPC avance etait mediocre, avec des taux a 5 ans Methodes Les patients (n = 854 ; CM 017/057 regroupes) atteints d’un CBNPC avance, avec un ECOG PS ≤ 1 et dont la maladie avait progresse pendant ou apres une premiere ligne de chimiotherapie ont ete randomises 1 :1 pour recevoir nivolumab 3 mg/kg toutes les 2 semaines ou docetaxel 75 mg/m2 toutes les 3 semaines jusqu’a progression ou toxicite inacceptable. La SG etait le critere principal d’evaluation pour les deux etudes. Resultats A 5 ans de suivi, 50 patients dans le bras nivolumab et 9 patients dans le bras docetaxel etaient en vie. Les caracteristiques initiales des survivants a 5 ans dans les deux bras etaient similaires a celles de la population globale et a celles des patients ayant survecu Conclusion Les CM 017 et CM 057 sont les premiers essais de phase III a rapporter les resultats a 5 ans d’un anti-PD1 dans le CBNPC avance prealablement traite et font etat d’une augmentation de plus de 4 fois des taux de SG a 5 ans avec nivolumab (13 %) par rapport au docetaxel (3 %). Le traitement par nivolumab reste bien tolere, sans nouveau signal de toxicite.

BACKGROUND Variable chemotherapy exposure may cause toxicity or lack of efficacy. This study was initiated to validate pharmacokinetically (PK)-guided paclitaxel dosing in patients with advanced non-small-cell lung cancer (NSCLC) to avoid supra- or subtherapeutic exposure. PATIENTS AND METHODS Patients with newly diagnosed, advanced NSCLC were randomly assigned to receive up to 6 cycles of 3-weekly carboplatin AUC 6 or cisplatin 80 mg/m(2) either with standard paclitaxel at 200 mg/m(2) (arm A) or PK-guided dosing of paclitaxel (arm B). In arm B, initial paclitaxel dose was adjusted to body surface area, age, sex, and subsequent doses were guided by neutropenia and previous-cycle paclitaxel exposure [time above a plasma concentration of 0.05 µM (Tc>0.05)] determined from a single blood sample on day 2. The primary end point was grade 4 neutropenia; secondary end points included neuropathy, radiological response, progression-free survival (PFS) and overall survival (OS). RESULTS Among 365 patients randomly assigned, grade 4 neutropenia was similar in both arms (19% versus 16%; P = 0.10). Neuropathy grade ≥2 (38% versus 23%, P < 0.001) and grade ≥3 (9% versus 2%, P < 0.001) was significantly lower in arm B, independent of the platinum drug used. The median final paclitaxel dose was significantly lower in arm B (199 versus 150 mg/m(2), P < 0.001). Response rate was similar in arms A and B (31% versus 27%, P = 0.405), as was adjusted median PFS [5.5 versus 4.9 months, hazard ratio (HR) 1.16, 95% confidence interval (CI) 0.91-1.49, P = 0.228] and OS (10.1 versus 9.5 months, HR 1.05, 95% CI 0.81-1.37, P = 0.682). CONCLUSION PK-guided dosing of paclitaxel does not improve severe neutropenia, but reduces paclitaxel-associated neuropathy and thereby improves the benefit-risk profile in patients with advanced NSCLC. CLINICAL TRIAL INFORMATION NCT01326767 (https://clinicaltrials.gov/ct2/show/NCT01326767).

At the University of Alabama at Birmingham, a partnership formed between faculty in the School of Nursing, the School of Engineering, the Honors College, and UAB Hospital to facilitate interaction between students of biomedical engineering and clinicians. Clinicians needed a way to address their unsolved problems in delivery of health care and students needed a way to engage in meaningful real-world clinical experiences. The authors identified barriers to clinical innovation, created formal freshman and sophomore level courses to lower those barriers, and created a web-based tool to facilitate bringing together domains of expertise. The courses provide a formal mechanism for students to engage in clinical innovation. The web tool creates a collaborative innovation hub that provides a pathway for clinicians at UAB Hospital to enter their problems into a viewable database. The web tool also allows users to form project teams and use built-in functionality to enhance the possibility that they will successfully solve significant problems. Results to date have demonstrated that clinicians are invested in students' efforts to improve approaches to patient care, students are empowered to seek challenging clinical innovation opportunities, and interacting in a digital space represents a viable way to improve collaboration.

Accessible high-capacity weighing scales are scarce in healthcare facilities, in part due to high device cost and weight. This shortage impairs weight monitoring and health maintenance for people with disabilities and/or morbid obesity. We conducted this study to design and validate a lighter, lower cost, high-capacity accessible weighing device. A prototype featuring 360 kg (800 lbs) of weight capacity, a wheelchair-accessible ramp, and wireless data transmission was fabricated. Forty-five participants (20 standing, 20 manual wheelchair users, and five power wheelchair users) were weighed using the prototype and a calibrated scale. Participants were surveyed to assess perception of each weighing device and the weighing procedure. Weight measurements between devices demonstrated a strong linear correlation (R2 = 0.997) with absolute differences of 1.4 ± 2.0% (mean±SD). Participant preference ratings showed no difference between devices. The prototype weighed 11 kg (38%) less than the next lightest high-capacity commercial device found by author survey. The prototype’s estimated commercial price range, $500–$600, is approximately half the price of the least expensive commercial device found by author survey. Such low cost weighing devices may improve access to weighing instrumentation, which may in turn help eliminate current health disparities. Future work is needed to determine the feasibility of market transition.

One approach to encourage and facilitate exercise is through interaction with virtual environments. The present study assessed the utility of Microsoft Kinect as an interface for choosing between multiple routes within a virtual environment through body gestures and voice commands. The approach was successfully tested on 12 individuals post-stroke and 15 individuals with cerebral palsy (CP). Participants rated their perception of difficulty in completing each gesture using a 5-point Likert scale questionnaire. The "most viable" gestures were defined as those with average success rates of 90% or higher and perception of difficulty ranging between easy and very easy. For those with CP, hand raises, hand extensions, and head nod gestures were found most viable. For those post-stroke, the most viable gestures were torso twists, head nods, as well as hand raises and hand extensions using the less impaired hand. Voice commands containing two syllables were viable (85% successful) for those post-stroke; however, participants with CP were unable to complete any voice commands with a high success rate. This study demonstrated that Kinect may be useful for persons with mobility impairments to interface with virtual exercise environments, but the effectiveness of the various gestures depends upon the disability of the user.

It is well documented that electrospun tissue engineering scaffolds can be fabricated with variable degrees of fiber alignment to produce scaffolds with anisotropic mechanical properties. Several attempts have been made to quantify the degree of fiber alignment within an electrospun scaffold using image-based methods. However, these methods are limited by the inability to produce a quantitative measure of alignment that can be used to make comparisons across publications. Therefore, we have developed a new approach to quantifying the alignment present within a scaffold from scanning electron microscopic (SEM) images. The alignment is determined by using the Sobel approximation of the image gradient to determine the distribution of gradient angles with an image. This data was fit to a Von Mises distribution to find the dispersion parameter κ, which was used as a quantitative measure of fiber alignment. We fabricated four groups of electrospun polycaprolactone (PCL) + Gelatin scaffolds with alignments ranging from κ = 1.9 (aligned) to κ = 0.25 (random) and tested our alignment quantification method on these scaffolds. It was found that our alignment quantification method could distinguish between scaffolds of different alignments more accurately than two other published methods. Additionally, the alignment parameter κ was found to be a good predictor the mechanical anisotropy of our electrospun scaffolds. The ability to quantify fiber alignment within and make direct comparisons of scaffold fiber alignment across publications can reduce ambiguity between published results where cells are cultured on "highly aligned" fibrous scaffolds. This could have important implications for characterizing mechanics and cellular behavior on aligned tissue engineering scaffolds. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1680-1686, 2016.

BACKGROUND Good outcomes have been described for pediatric lateral condyle fractures treated by open reduction and fixation using either screws or Kirschner wires (K-wires). No studies have compared the biomechanical properties of the 2 fixation methods. We hypothesized that screw fixation would be more biomechanically stable than K-wire fixation. METHODS Synthetic humerus models were used for biomechanical testing, following a previously published protocol. A miter saw was used to make an oblique cut to simulate a Milch type II fracture. Fractures were anatomically reduced and fixed with either 2 divergent 0.062-inch K-wires placed bicortically or a 4.0-mm lag screw placed obliquely (perpendicular to the fracture line). Specimens were then embedded in polymethyl methacrylate bone cement for testing. Mechanical testing using displacement control was performed applying compression or distraction from 0 to 1.5 mm at a rate of 0.5 mm/s for 10 cycles. The maximum force was calculated based on the maximum force averaged over the 10 cycles. Stiffness was calculated based on the slope of the force-displacement curve of the 10th cycle. A 2-sample t test was used to determine significant differences between the stiffness and maximum force comparing the K-wire and screw groups. A P-value of

Purpose To determine biomechanical differences between a fixed-angle locking volar titanium plate (VariAx; Stryker, Kalamazoo, MI) and a fixed-angle compression locking volar stainless steel plate (CoverLoc Volar Plate; Tornier, Amsterdam, Netherlands) in the fixation of simulated AO C3 distal radius fractures. Methods Eighteen cadaveric upper extremities (9 matched pairs) with an average age of 54 years were tested. A 4-part AO C3 fracture pattern was created in each specimen. The fractures were reduced under direct vision and fixed with either the fixed-angle locking volar titanium plate or the fixed-angle compression locking volar stainless steel plate. Motion tracking analysis was then performed while the specimens underwent cyclic loading. Changes in displacement, rotation, load to failure, and mode of failure were recorded. Results The fragments, when secured with the fixed-angle compression locking stainless steel construct, demonstrated less displacement and rotation than the fragments secured with the fixed-angle locking titanium plate under physiological loading conditions. In the fixed-angle compression locking stainless steel group, aggregate displacement and rotation of fracture fragments were 5 mm and 3° less, respectively, than those for the fixed-angle locking titanium group. The differences between axial loads at mechanical failure and stiffness were not statistically significant. The compression locking stainless steel group showed no trend in mode of failure, and the locking titanium plate group failed most often by articular fixation failure (5 of 9 specimens). Conclusions The fixed-angle compression locking stainless steel volar plate may result in less displacement and rotation of fracture fragments in the fixation of AO C3 distal radius fractures than fixation by the fixed-angle locking volar titanium plate. However, there were no differences between the plates in mechanical load to failure and stiffness. Clinical relevance Fixation of distal radius AO C3 fracture patterns with the fixed-angle compression locking stainless steel plate may provide improved stability of fracture fragments.

Background Guidelines for metastatic non-small cell lung cancer recommend stratified treatment by biomarker test results. We used CRISP to evaluate treatment and outcome of patients (pts) in whom neither targetable molecular alterations nor any PD-L1 expression were detected. Methods Currently 163 sites in Germany have recruited >3700 pts at start of 1st-line who will be followed until death or end of project. Data from 2204 pts recruited by 133 sites from 12/2015 to 06/2018 was analyzed. These pts started treatment prior approval of immune checkpoint inhibitors (ICI) for this group of pts. Progression-free survival (PFS) was determined in pts ≥1 year under observation (recruited until 06/2017 (n = 906), outcome sample (ous)). Results 6% of pts with non-squamous (nsq) and 35% with squamous (sq) tumors received no type of biomarker testing prior to start of 1st-line, and in 49% and 36% no targetable alterations or any PD-L1 expression were detected. Thus, 55% and 71% of pts (nsq/sq) were eligible for chemotherapy (ctx) but no type of targeted therapy at start of 1st-line. Median age at start of 1st-line was 66 and 68 years (nsq/sq). 29%/23% had ECOG=0 and 82%/90% ≤1 comorbidity. 10%/6% were never-smokers. In 1st-line, pts received carboplatin- (55%) or cisplatin-based ctx (24%), 13% targeted therapy (e.g. ICI in trial, switch to TKI but test result not yet documented). At database cut, 33% of all pts had started 2nd-line, 24% had died prior to a 2nd-line and remaining pts were still in 1st-line. In the ous, median PFS was 5.0 months (66% events, 95%-CI 4.5-5.5 months, n = 457) for nsq tumors and 4.5 months (66% events, 95%-CI 3.4-5.3 months, n = 154) for sq tumors. In total 55% of pts with nsq and 53% of pts with sq tumors had died. Conclusions CRISP presents current real life data from Germany. Despite break-throughs with targeted therapies and high test rates in routine care, the majority of pts do not qualify for targeted therapy because no targetable alterations are found. First outcome results indicate that prognosis is poor in these pts. Outcome will hopefully improve in the cohort now treated with ctx-ICI combination. Clinical trial identification NCT02622581. Legal entity responsible for the study AIO-Studien-gGmbH. Funding AstraZeneca GmbH, Boehringer Ingelheim Pharma GmbH & Co. KG, Bristol-Myers Squibb GmbH & Co. KGaA, Celgene GmbH, MSD Sharp & Dohme GmbH, Lilly Deutschland GmbH, Novartis Pharma GmbH, Pfizer Pharma GmbH, Roche Pharma AG, and Takeda Pharma Vertriebs GmbH & Co. KG. Disclosure F. Griesinger: Honoraria (self), Advisory / Consultancy: Ariad; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): AstraZeneca; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Boehringer Ingelheim; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Bristol-Myer-Squibb; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Celgene; Honoraria (self), Advisory / Consultancy: Clovis; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Lilly; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Merck-Sharp-Dome; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Novartis; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Pfizer; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Roche. N.W. Marschner: Honoraria (institution), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Celgene; Honoraria (institution), Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Lilly; Advisory / Consultancy, Research grant / Funding (institution): MSD Sharp & Dohme ; Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Novartis; Research grant / Funding (institution), Travel / Accommodation / Expenses: Pfizer; Leadership role, Shareholder / Stockholder / Stock options, Officer / Board of Directors: iOMEDICO. M. Janicke: Leadership role, Full / Part-time employment: iOMEDICO. A. Fleitz: Full / Part-time employment: iOMEDICO. L. Spring: Full / Part-time employment: iOMEDICO. J. Sahlmann: Leadership role, Full / Part-time employment: iOMEDICO. A. Karatas: Research grant / Funding (institution): AstraZeneca ; Research grant / Funding (institution): Boehringer Ingelheim; Research grant / Funding (institution): Bristol-Myers Squibb; Research grant / Funding (institution): Celgene; Research grant / Funding (institution): MSD Sharp & Dohme; Research grant / Funding (institution): Lilly; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Roche; Research grant / Funding (institution): Takeda. A. Hipper: Research grant / Funding (institution): Takeda; Research grant / Funding (institution): Roche; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): Lilly; Research grant / Funding (institution): MSD Sharp & Dohme; Research grant / Funding (institution): Celgene; Research grant / Funding (institution): Bristol-Myers Squibb; Research grant / Funding (institution): Boehringer Ingelheim; Research grant / Funding (institution): AstraZeneca. M. Sebastian: Advisory / Consultancy: Bristol-Myers Squibb ; Advisory / Consultancy: MSD Sharp & Dohme ; Advisory / Consultancy: Roche; Advisory / Consultancy: Novartis; Advisory / Consultancy: AstraZeneca; Advisory / Consultancy: Boehringer Ingelheim Pharma; Advisory / Consultancy: Celgene; Advisory / Consultancy: Lilly; Advisory / Consultancy: Pfizer. M. Thomas: Advisory / Consultancy, Travel / Accommodation / Expenses: MSD Sharp & Dohme ; Advisory / Consultancy, Travel / Accommodation / Expenses: Bristol-Myers Squibb ; Advisory / Consultancy, Travel / Accommodation / Expenses: Lilly; Advisory / Consultancy, Travel / Accommodation / Expenses: AstraZeneca ; Advisory / Consultancy, Travel / Accommodation / Expenses: Roche; Advisory / Consultancy, Travel / Accommodation / Expenses: Pfizer; Advisory / Consultancy, Travel / Accommodation / Expenses: Celgene; Advisory / Consultancy, Travel / Accommodation / Expenses: Novartis. All other authors have declared no conflicts of interest.

Cardiac tamponade is a life-threatening compression of the heart due to accumulation of fluid surrounding the heart. It occurs in two out of 10 000 people annually and is universally fatal if the fluid is not timely drained.1 The more rapidly accumulation occurs, the quicker the patient develops symptoms, including dyspnoea, fatigue and chest pain.2 Vital sign changes include tachycardia, tachypnoea and hypotension with a narrow pulse pressure. Pericardiocentesis is the required treatment to drain this fluid improving cardiac output.3 Simulation is an adjunct education tool to practise rare but crucial procedures.1 Current manikins do not have the capabilities to practise pericardiocentesis. Only torso task trainers are available.4 5 Our objective was to develop a pericardiocentesis trainer model that could both reliably recreate the procedure and be placed in a manikin, with no fluid leakage. ### Model assembly and design The Department of Biomedical Engineering collaborated with the Department of Pediatrics to build an inexpensive pericardiocentesis model with the following constraints: 1. Fit existing child simulators without significant chest wall distortion. 2. Have components to protect simulator both structurally and electronically from fluid spills using self-sealing technology. 3. Provide realistic fluid removal. 4. Have easily refillable fluid compartment that does not require direct access to task trainer. 5. Costs less than $500 budget. The final design encompasses a two-piece tray system, a top and bottom tray, attached by a peg …

There exists a need for educational processes in which students gain experience with design and commercialization of medical devices. This manuscript describes the implementation of, and assessment results from, the first year offering of a project course sequence in Master of Engineering (MEng) in Design and Commercialization at our institution. The three-semester course sequence focused on developing and applying hands-on skills that contribute to product development to address medical device needs found within our university hospital and local community. The first semester integrated computer-aided drawing (CAD) as preparation for manufacturing of device-related components (hand machining, computer numeric control (CNC), three-dimensional (3D) printing, and plastics molding), followed by an introduction to microcontrollers (MCUs) and printed circuit boards (PCBs) for associated electronics and control systems. In the second semester, the students applied these skills on a unified project, working together to construct and test multiple weighing scales for wheelchair users. In the final semester, the students applied industrial design concepts to four distinct device designs, including user and context reassessment, human factors (functional and aesthetic) design refinement, and advanced visualization for commercialization. The assessment results are described, along with lessons learned and plans for enhancement of the course sequence.

The objective of this study was to demonstrate that functional, quantitative magnetic resonance myelography (MRM) allows standardized diagnosis of symptomatic lumbar spinal stenoses which show at least equal detectability compared to functional myelography and postmyelographic CT (pmCT) based on intra- and postoperative findings.We investigated 43 volunteers and 47 patients with symptomatic lumbar spinal stenoses using MRM in normal position as well as in flexion and extension in a standard whole-body MR scanner. Twenty volunteers were additionally examined under axial loading. All patients were investigated by functional myelography and pmCT and 10 patients had a functional lumbar MRM postoperatively. Range of motion and cerebrospinal fluid (CSF) volumes in normal position, flexion, extension, and under axial loading (volunteers) were assessed for each segment. Detectability was determined by using intraoperative findings, and postoperative freedom of symptoms was correlated with CSF volume changes in MRM.The ranges of motion in a standard whole-body MR scanner provide adequate scope for investigations into function (flexion and extension) in both volunteers and patients. Axial loading was associated with a mechanism of extension, albeit to a far smaller extent. Detectability of lumbar stenoses was 100% for MRM, 58% for conventional myelography, and 68% for pmCT. Postoperative changes in CSF volume of levels with stenoses in MRM strongly correlated with freedom of symptoms (R = 0.772).This MRM method allows for exact diagnosis and reproducible quantification of stenoses, motion-related changes, and spondylolistheses of the lumbar spine. It may be useful for early detection of alterations in order to avoid neuronal compression.

ObjectThe goal of this study was to investigate the usefulness and diagnostic potential of an improved MR myelography approach using a dedicated, heavily T2-weighted, 3D MRI sequence in combination with image fusion. A further aim was to compare dural areas and volumes of normal and pathological altered lumbar spine levels, and accuracy in the assessment of the stenoses, with those obtained by postmyelographic CT.MethodsFifty patients underwent myelography, postmyelographic CT, and the improved MR myelography approach using a dedicated, heavily T2-weighted, 3D MRI sequence and image fusion. Dural cross-sectional areas and volumes for normal lumbar levels and levels with stenosis were calculated for postmyelographic CT and MR myelography data. The significant differences and Pearson correlations between dural cross-sectional areas and volumes from L1–2 to L5–S1 of postmyelographic CT and MR myelography were analyzed. The 99% CIs for normal and stenotic levels in patients with claudication distances less than 100 meters were calculated.ResultsFor both dural areas and volumes in normal lumbar levels, the authors found no significant differences and strong correlations between postmyelographic CT and MR myelography. For the lower lumbar levels (L4–5 and L5–S1) they found significantly larger dural areas on MR myelography compared with postmyelographic CT, but not for the upper levels (L2–3 and L3–4). Dural volume analysis revealed significantly larger volumes for MR myelography at all 4 lumbar levels with stenoses in the cohort (L2–3 to L5–S1). Complete separation with no overlap was found between the 99% CIs for normal levels and stenotic levels.ConclusionsDifferences in dural areas and volumes in this study may have been caused by the fact that in the case of a severely compressed thecal sac, the viscosity of the intrathecally applied contrast agent is too high in the framework of myelography. The gravitationally dependent component is thus too low to achieve sufficient fluid contrast. An optimized MR myelography approach—a dedicated 3D MR myelography sequence with high spatial resolution in combination with image fusion—is required to achieve a more reliable diagnosis of lumbar spine stenoses, especially with severe compression, compared with postmyelographic CT. This MR myelography approach may be helpful in preventing overestimation of lumbar spine stenoses. The upper limits of 99% CIs for stenotic levels can be interpreted as an indication for surgical treatment. However, further studies that include postoperative outcomes are required.

The tissue-suture interface remains the weakest aspect of a rotator cuff repair, highlighting the importance of identifying techniques to improve stitch strength. Choice of suture-passing devices, size of the tissue bite, and stitch configuration are variables that may influence stitch strength and therefore repair stability.To evaluate the effect that size of the tissue penetrator device and tissue bite size have upon the holding strength of commonly used stitches.Controlled laboratory study.Three different-sized tissue-penetrating devices, small circular, midsized circular, and large rectangular, were used to place sutures in 192 infraspinatus tendon grafts of sheep. Tissue bite sizes of either 0.5 cm or 1.0 cm for 4 different stitches, a simple, mattress, modified Mason-Allen (MMA), and massive cuff (MAC) stitch, were tested. Grafts were cyclically loaded and then loaded to failure. Mixed multivariate regression analysis was used to test the effect of instrument, bite size, and stitch configuration on peak-to-peak displacement, cyclic elongation, and load to failure.The average ultimate load to failure with the smallest penetrating device was 112 N, significantly higher than with both the midsized (95 N) and large devices (91 N) (P.001). The average load to failure was 31 N higher for a 1.0-cm bite size when compared with a 0.5-cm bite size (P.001). The largest load-to-failure differences were found with the type of stitch placed: simple, 48 N; mattress, 69 N; MMA, 130 N; and MAC, 152 N (all P.02). For simple and mattress stitches, each additional pass of the suture increased the load to failure by 21 N. In MMA and MAC stitches, an additional pass resulted in an increase in the load to failure by 50 N. Cyclic elongation did not differ by instrument type (all P.5). The elongation of stitches with a 1.0-cm bite size was 0.14 mm higher than stitches with a 0.5-cm bite size (P.001). No meaningful difference in peak-to-peak displacement was seen for bite size, instrument type, or stitch construct.The strength of rotator cuff stitches was significantly affected by the different-sized tissue-penetrating instruments and size of the bite. However, the greatest predictor of time-zero stitch strength is the type of stitch placed.This study highlights the importance of stitch configuration in the repair of rotator cuff tears.

Ziel: Ziel war es zu zeigen, dass der bei der MR-Myelografie durch die starke T2-Gewichtung auftretende Nachteil der fehlenden anatomischen Zuordnung, durch eine Bildfusion sowie durch in koronarer Phasenkodierrichtung generierte Quellbilder behoben werden kann, wodurch eine dem Goldstandard – dem postmyelografischen CT – vergleichbare Bildinformation erzielt werden kann. Material und Methoden: Untersucht wurden insgesamt 110 Patienten mit extraduralen Pathologien der HWS und der LWS. Alle Patienten erhielten eine 3D-MR-Myelografie und ein postmyelografisches CT. Anschliesend wurden die MRT-Datensatze durch Bildfusion und Rekonstruktionen nachverarbeitet und mit den entsprechenden Schnittbildern des postmyelografischen CT verglichen. Ergebnisse: Die in der Arbeit verwendete Visualisierungstechnik (3D-MR-Myelografie) ist hierbei in der Lage intradurale Substrukturen hochauflosend und artefaktfrei darzustellen. Die erreichbaren Visualisierungsergebnisse sind mit dem aktuellen Goldstandard (postmyelografisches CT) vergleichbar. Eine anatomische Zuordnung ist durch Verwendung uberlagerter MRT-Sequenzen im Rahmen einer Bildfusion moglich. Die hierzu notwendigen Arbeitsschritte lassen sich rasch umsetzen und sind auf kommerziellen Workstations verfugbar. Schlussfolgerung: Durch die Fusion von unterschiedlichen MRT-Sequenzen entstehen neue Qualitaten bei der Visualisierung komplexer 3D-Datensatze. Insbesondere konnen der konventionellen Myelografie einschlieslich der postmyelografischen CT vergleichbare Visualisierungsergebnisse in Form der sogenannten 3D-MR-Myelografie realisiert werden. Der durch die starke T2-Gewichtung verlorene Bezug zu anatomischen Leitstrukturen kann durch Fusion mit einem weiteren MRT-Datensatz ausgeglichen werden.

Background: The tissue-suture interface remains the most common site of failure in rotator cuff repairs. It is currently unknown if arthroscopic sliding knots injure the tissue and weaken the suture-tendon interface. Purpose: To evaluate the effect sliding knots have on the strength of the suture-tendon interface. Study Design: Controlled laboratory study. Methods: A total of 32 sheep infraspinatus tendons were randomized among 4 groups of stitches (n = 8): simple-static, simple-sliding, mattress-static, and mattress-sliding. All high-strength, No. 2 suture stitch-knot combinations were created in an arthroscopic simulated environment, and sliding knots were tied with shortening of the suture and sliding of the knot down to the tissue interface to simulate surgical technique. Each graft was cyclically loaded on a mechanical testing system from 5 to 20 N for 20 cycles and then loaded to failure. A least squares analysis of variance model was used to test significance of sliding stitches upon cyclic elongation, peak-to-peak displacement, and ultimate load. Estimated means and standard deviations are reported from the regression model. Results: A mattress-static stitch (116 N) was significantly stronger than a mattress-sliding stitch (70 N; P < .001). The ultimate loads for the simple-static (46 N) and sliding (50 N) stitches were not statistically different. For cyclic elongation, the only difference was the mattress-sliding stitch (0.95 mm) having a greater elongation than the simple-static (0.61 mm; P = .01) and simple-sliding (0.68 mm; P = .04) stitches. Both mattress stitches had significantly less peak-to-peak displacement (0.39 and 0.41 mm) than the simple stitches (0.47 and 0.46 mm; P < .001). Conclusion: Sliding suture through tissue weakens the suture-tendon interface in mattress stitch constructs but not in simple stitch constructs. Mattress stitches have superior holding strength compared with simple stitches. Clinical Relevance: Clinical relevance is uncertain. In situations with poor tissue quality or concern regarding tension across the repair, consideration should be given to using static knots as opposed to sliding knots when placing mattress stitches.

Introduction In the U.S. alone, an estimated 30,000 knee–thigh–hip (KTH) injuries occur annually in frontal motor vehicle collisions. These fractures typically occur through occupant contact with the vehicle's knee bolster. Research has suggested that knee airbags (KABs) can mitigate the forces sustained during this contact, resulting in decreased injury risk; however, previous research has been limited by small sample sizes or by occurring in a controlled setting. The objective of the current study is to determine the effectiveness of KABs on KTH fracture risk using nationally representative, real-world data. Methods Using combined data from the Crash Injury Research and Engineering Network and the National Automotive Sampling Survey, a matched cohort study was conducted among front-seat occupants of vehicles involved in a frontal collision occurring from 2000 to 2009. Occupants exposed to a KAB deployment were matched to occupants with no KAB deployment based on age ±5 years, sex, seatbelt use, vehicle seating position (i.e., driver or front passenger), car vehicle body type, collision impact, and sampling weight. A Cox proportional hazards model was used to calculate risk ratios (RRs) and associated 95% confidence intervals (95% CI) to estimate the association between KAB deployment and lower extremity fracture risk. Results There was no association between KAB deployment and risk of lower extremity fracture (RR 0.83, 95% CI 0.52–1.31). A notable pattern in fracture risk, though not statistically significant, was observed, with a decreased risk of hip (RR 0.72, 95% CI 0.26–1.97) and thigh fracture (RR 0.81, 95% CI 0.32–2.05), and an increased risk of tibia/fibula (RR 1.23, 95% CI 0.52–2.90) and foot fracture (RR 1.96, 95% CI 0.72–5.32). Conclusions The results of the current study suggest that KABs are not associated with the risk of lower extremity fractures. However, given the small sample size of the current study, it is difficult to definitively say whether the observed injury pattern is representative of the true pattern.