@article{YangKriechbaumerAlbrachtetal.2015, author = {Yang, Peng-Fei and Kriechbaumer, Andreas and Albracht, Kirsten and Sanno, Maximilian and Ganse, Bergita and Koy, Timmo and Shang, Peng and Br{\"u}ggemann, Gert-Peter and M{\"u}ller, Lars Peter and Rittweger, J{\"o}rn}, title = {On the relationship between tibia torsional deformation and regional muscle contractions in habitual human exercises in vivo}, series = {Journal of Biomechanics}, volume = {48}, journal = {Journal of Biomechanics}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0021-9290}, doi = {10.1016/j.jbiomech.2014.12.031}, pages = {456 -- 464}, year = {2015}, language = {en} } @article{BelavyAlbrachtBruggemannetal.2016, author = {Belavy, Daniel L. and Albracht, Kirsten and Bruggemann, Gert-Peter and Vergroesen, Pieter-Paul A. and Dieen, Jaap H. van}, title = {Can exercise positively influence the intervertebral disc?}, series = {Sports Medicine}, volume = {46}, journal = {Sports Medicine}, number = {4}, publisher = {Springer}, address = {Berlin}, issn = {1179-2035}, doi = {10.1007/s40279-015-0444-2}, pages = {473 -- 485}, year = {2016}, abstract = {To better understand what kinds of sports and exercise could be beneficial for the intervertebral disc (IVD), we performed a review to synthesise the literature on IVD adaptation with loading and exercise. The state of the literature did not permit a systematic review; therefore, we performed a narrative review. The majority of the available data come from cell or whole-disc loading models and animal exercise models. However, some studies have examined the impact of specific sports on IVD degeneration in humans and acute exercise on disc size. Based on the data available in the literature, loading types that are likely beneficial to the IVD are dynamic, axial, at slow to moderate movement speeds, and of a magnitude experienced in walking and jogging. Static loading, torsional loading, flexion with compression, rapid loading, high-impact loading and explosive tasks are likely detrimental for the IVD. Reduced physical activity and disuse appear to be detrimental for the IVD. We also consider the impact of genetics and the likelihood of a 'critical period' for the effect of exercise in IVD development. The current review summarises the literature to increase awareness amongst exercise, rehabilitation and ergonomic professionals regarding IVD health and provides recommendations on future directions in research.}, language = {en} } @article{KolditzAlbinAbeletal.2016, author = {Kolditz, Melanie and Albin, Thivaharan and Abel, Dirk and Fasse, Alessandro and Br{\"u}ggemann, Gert-Peter and Albracht, Kirsten}, title = {Evaluation of foot position and orientation as manipulated variables to control external knee adduction moments in leg extension training}, series = {Computer methods and programs in biomedicine}, volume = {171}, journal = {Computer methods and programs in biomedicine}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0169-2607}, doi = {10.1016/j.cmpb.2016.09.005}, pages = {81 -- 86}, year = {2016}, abstract = {Background and Objective Effective leg extension training at a leg press requires high forces, which need to be controlled to avoid training-induced damage. In order to avoid high external knee adduction moments, which are one reason for unphysiological loadings on knee joint structures, both training movements and the whole reaction force vector need to be observed. In this study, the applicability of lateral and medial changes in foot orientation and position as possible manipulated variables to control external knee adduction moments is investigated. As secondary parameters both the medio-lateral position of the center of pressure and the frontal-plane orientation of the reaction force vector are analyzed. Methods Knee adduction moments are estimated using a dynamic model of the musculoskeletal system together with the measured reaction force vector and the motion of the subject by solving the inverse kinematic and dynamic problem. Six different foot conditions with varying positions and orientations of the foot in a static leg press are evaluated and compared to a neutral foot position. Results Both lateral and medial wedges under the foot and medial and lateral shifts of the foot can influence external knee adduction moments in the presented study with six healthy subjects. Different effects are observed with the varying conditions: the pose of the leg is changed and the direction and center of pressure of the reaction force vector is influenced. Each effect results in a different direction or center of pressure of the reaction force vector. Conclusions The results allow the conclusion that foot position and orientation can be used as manipulated variables in a control loop to actively control knee adduction moments in leg extension training.}, language = {en} } @article{Staat2012, author = {Staat, Manfred}, title = {Limit and shakedown analysis under uncertainty}, series = {Tap chi Khoa hoc \& ung dung - Dai hoc Ton Duc Thang}, volume = {19}, journal = {Tap chi Khoa hoc \& ung dung - Dai hoc Ton Duc Thang}, pages = {45 -- 47}, year = {2012}, language = {en} } @article{NiedermeyerZhouDursunetal.2016, author = {Niedermeyer, Angela and Zhou, Bei and Dursun, G{\"o}zde and Temiz Artmann, Ayseg{\"u}l and Markert, Bernd}, title = {An examination of tissue engineered scaffolds in a bioreactor}, series = {Proceedings in Applied Mathematics and Mechanics PAMM}, volume = {16}, journal = {Proceedings in Applied Mathematics and Mechanics PAMM}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1617-7061}, doi = {10.1002/pamm.201610038}, pages = {99 -- 100}, year = {2016}, abstract = {Replacement tissues, designed to fill in articular cartilage defects, should exhibit the same properties as the native material. The aim of this study is to foster the understanding of, firstly, the mechanical behavior of the material itself and, secondly, the influence of cultivation parameters on cell seeded implants as well as on cell migration into acellular implants. In this study, acellular cartilage replacement material is theoretically, numerically and experimentally investigated regarding its viscoelastic properties, where a phenomenological model for practical applications is developed. Furthermore, remodeling and cell migration are investigated.}, language = {en} } @article{LeversStaatLaack2016, author = {Levers, A. and Staat, Manfred and Laack, Walter van}, title = {Analysis of the long-term effect of the MBST® nuclear magnetic resonance therapy on gonarthrosis}, series = {Orthopedic Practice}, volume = {47}, journal = {Orthopedic Practice}, number = {11}, pages = {521 -- 528}, year = {2016}, language = {en} } @inproceedings{TranTranMatthiesetal.2016, author = {Tran, Ngoc Trinh and Tran, Thanh Ngoc and Matthies, Hermann G. and Stavroulakis, Georgios Eleftherios and Staat, Manfred}, title = {FEM Shakedown of uncertain structures by chance constrained programming}, series = {PAMM Proceedings in Applied Mathematics and Mechanics}, volume = {16}, booktitle = {PAMM Proceedings in Applied Mathematics and Mechanics}, number = {1}, issn = {1617-7061}, doi = {10.1002/pamm.201610346}, pages = {715 -- 716}, year = {2016}, language = {en} } @inproceedings{StaatDuong2016, author = {Staat, Manfred and Duong, Minh Tuan}, title = {Smoothed Finite Element Methods for Nonlinear Solid Mechanics Problems: 2D and 3D Case Studies}, series = {Proceedings of the National Science and Technology Conference on Mechanical - Transportation Engineering (NSCMET 2016), 13th October 2016, Hanoi, Vietnam, Vol.2}, booktitle = {Proceedings of the National Science and Technology Conference on Mechanical - Transportation Engineering (NSCMET 2016), 13th October 2016, Hanoi, Vietnam, Vol.2}, pages = {440 -- 445}, year = {2016}, abstract = {The Smoothed Finite Element Method (SFEM) is presented as an edge-based and a facebased techniques for 2D and 3D boundary value problems, respectively. SFEMs avoid shortcomings of the standard Finite Element Method (FEM) with lower order elements such as overly stiff behavior, poor stress solution, and locking effects. Based on the idea of averaging spatially the standard strain field of the FEM over so-called smoothing domains SFEM calculates the stiffness matrix for the same number of degrees of freedom (DOFs) as those of the FEM. However, the SFEMs significantly improve accuracy and convergence even for distorted meshes and/or nearly incompressible materials. Numerical results of the SFEMs for a cardiac tissue membrane (thin plate inflation) and an artery (tension of 3D tube) show clearly their advantageous properties in improving accuracy particularly for the distorted meshes and avoiding shear locking effects.}, language = {en} } @inproceedings{BhattaraiFrotscherStaat2016, author = {Bhattarai, Aroj and Frotscher, Ralf and Staat, Manfred}, title = {Significance of fibre geometry on passive-active response of pelvic muscles to evaluate pelvic dysfunction}, series = {BioMedWomen: Proceedings of the international conference on clinical and bioengineering for women's health}, booktitle = {BioMedWomen: Proceedings of the international conference on clinical and bioengineering for women's health}, editor = {Natal Jorge, Renato}, publisher = {CRC Press}, address = {Boca Raton}, isbn = {978-1-138-02910-1}, pages = {185 -- 188}, year = {2016}, language = {en} } @article{HacklAndermahrStaatetal.2017, author = {Hackl, M. and Andermahr, J. and Staat, Manfred and Bremer, I. and Borggrefe, J. and Prescher, A. and M{\"u}ller, L. P. and Wegmann, K.}, title = {Suture button reconstruction of the central band of the interosseous membrane in Essex-Lopresti lesions: a comparative biomechanical investigation}, series = {The Journal of Hand Surgery (European Volume)}, volume = {42}, journal = {The Journal of Hand Surgery (European Volume)}, number = {4}, publisher = {Sage}, address = {London}, issn = {2043-6289 (Online)}, doi = {10.1177/1753193416665943}, pages = {370 -- 376}, year = {2017}, language = {en} } @article{AlbannaConzenWeissetal.2016, author = {Albanna, Walid and Conzen, Catharina and Weiss, Miriam and Clusmann, Hans and Fuest, Matthias and Mueller, Marguerite and Brockmann, Marc Alexander and Vilser, Walthard and Schmidt-Trucks{\"a}ss, Arno and Hoellig, Anke and Seiz, Marcel and Thom{\´e}, Claudius and Kotliar, Konstantin and Schubert, Gerrit Alexander}, title = {Retinal Vessel Analysis (RVA) in the context of subarachnoid hemorrhage: A proof of concept study}, series = {PLoS ONE}, volume = {11}, journal = {PLoS ONE}, number = {7}, publisher = {PLOS}, address = {San Francisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0158781}, pages = {13 Seiten}, year = {2016}, abstract = {Background Timely detection of impending delayed cerebral ischemia after subarachnoid hemorrhage (SAH) is essential to improve outcome, but poses a diagnostic challenge. Retinal vessels as an embryological part of the intracranial vasculature are easily accessible for analysis and may hold the key to a new and non-invasive monitoring technique. This investigation aims to determine the feasibility of standardized retinal vessel analysis (RVA) in the context of SAH. Methods In a prospective pilot study, we performed RVA in six patients awake and cooperative with SAH in the acute phase (day 2-14) and eight patients at the time of follow-up (mean 4.6±1.7months after SAH), and included 33 age-matched healthy controls. Data was acquired using a manoeuvrable Dynamic Vessel Analyzer (Imedos Systems UG, Jena) for examination of retinal vessel dimension and neurovascular coupling. Results Image quality was satisfactory in the majority of cases (93.3\%). In the acute phase after SAH, retinal arteries were significantly dilated when compared to the control group (124.2±4.3MU vs 110.9±11.4MU, p<0.01), a difference that persisted to a lesser extent in the later stage of the disease (122.7±17.2MU, p<0.05). Testing for neurovascular coupling showed a trend towards impaired primary vasodilation and secondary vasoconstriction (p = 0.08, p = 0.09 resp.) initially and partial recovery at the time of follow-up, indicating a relative improvement in a time-dependent fashion. Conclusion RVA is technically feasible in patients with SAH and can detect fluctuations in vessel diameter and autoregulation even in less severely affected patients. Preliminary data suggests potential for RVA as a new and non-invasive tool for advanced SAH monitoring, but clinical relevance and prognostic value will have to be determined in a larger cohort.}, language = {en} } @article{KotliarLanzl2016, author = {Kotliar, Konstantin and Lanzl, I. M.}, title = {Mit Statistik gemeistert: perfekte Augentropfen und idealer Screeningtest : M{\"o}glichkeiten und Grenzen statistischer Methoden beim Glaukom}, series = {Der Ophthalmologe: Zeitschrift Der Deutschen Ophthalmologischen Gesellschaft}, journal = {Der Ophthalmologe: Zeitschrift Der Deutschen Ophthalmologischen Gesellschaft}, number = {113}, publisher = {Springer}, address = {Berlin}, issn = {0941-293X}, doi = {10.1007/s00347-016-0312-y}, pages = {838 -- 843}, year = {2016}, abstract = {Hintergrund Die Anwendung und das Verst{\"a}ndnis von Statistik sind sehr wichtig f{\"u}r die biomedizinische Forschung und f{\"u}r die klinische Praxis. Dies gilt insbesondere auch zur Absch{\"a}tzung der M{\"o}glichkeiten unterschiedlichster Diagnostik- und Therapieoptionen beim Glaukom. Die scheinbare Komplexit{\"a}t der Statistik, die zum Teil dem „gesunden Menschenverstand" zu widersprechen scheint, zusammen mit der nur vorsichtigen Akzeptanz der Statistik bei vielen Medizinern k{\"o}nnen zu bewussten und unbewussten Manipulationen bei der Datendarstellung und -interpretation f{\"u}hren. Ziel der Arbeit Ziel ist die verst{\"a}ndliche Darstellung einiger typischer Fehler in der medizinisch-statistischen Datenbehandlung. Material und Methoden Anhand hypothetischer Beispiele aus der Glaukomdiagnostik erfolgen die Darstellung der Wirkung eines hypotensiven Medikamentes sowie die Beurteilung der Ergebnisse eines diagnostischen Tests. Es werden die typischsten statistischen Einsatzbereiche und Irrtumsquellen ausf{\"u}hrlich und verst{\"a}ndlich analysiert Ergebnisse Mechanismen von Datenmanipulation und falscher Dateninterpretation werden aufgekl{\"a}rt. Typische Irrtumsquellen bei der statistischen Auswertung und Datendarstellung werden dabei erl{\"a}utert. Schlussfolgerungen Die erl{\"a}uterten praktischen Beispiele zeigen die Notwendigkeit, die Grundlagen der Statistik zu verstehen und korrekt anwenden zu k{\"o}nnen. Fehlendes Grundlagenwissen und Halbwissen der medizinischen Statistik k{\"o}nnen zu folgenschweren Missverst{\"a}ndnissen und falschen Entscheidungen in der medizinischen Forschung, aber auch in der klinischen Praxis f{\"u}hren.}, language = {de} } @inproceedings{TranTranMatthiesetal.2016, author = {Tran, Ngoc Trinh and Tran, Thanh Ngoc and Matthies, H. G. and Stavroulakis, G. E. and Staat, Manfred}, title = {Shakedown analysis of plate bending analysis under stochastic uncertainty by chance constrained programming}, series = {ECCOMAS Congress 2016, VII European Congress on Computational Methods in Applied Sciences and Engineering. Crete Island, Greece, 5-10 June 2016}, booktitle = {ECCOMAS Congress 2016, VII European Congress on Computational Methods in Applied Sciences and Engineering. Crete Island, Greece, 5-10 June 2016}, editor = {Papadrakakis, M.}, pages = {13 S.}, year = {2016}, language = {en} } @inproceedings{DuongJungFrotscheretal.2016, author = {Duong, Minh Tuan and Jung, Alexander and Frotscher, Ralf and Staat, Manfred}, title = {A 3D electromechanical FEM-based model for cardiac tissue}, series = {ECCOMAS Congress 2016, VII European Congress on Computational Methods in Applied Sciences and Engineering. Crete Island, Greece, 5-10 June 2016}, booktitle = {ECCOMAS Congress 2016, VII European Congress on Computational Methods in Applied Sciences and Engineering. Crete Island, Greece, 5-10 June 2016}, editor = {Papadrakakis, M.}, pages = {13 S.}, year = {2016}, language = {en} } @article{WegmannHacklStaatetal.2016, author = {Wegmann, Kilian and Hackl, Michael and Staat, Manfred and Mayer, Katharina and M{\"u}ller, Lars-Peter}, title = {Double plate osteosynthesis of proximal ulna fractures: biomechanical and clinical results}, series = {Knee surgery, sports traumatology, arthroscopy}, volume = {Volume 24}, journal = {Knee surgery, sports traumatology, arthroscopy}, number = {Supplement 1}, publisher = {Springer}, address = {Berlin}, issn = {0942-2056}, doi = {10.1007/s00167-016-4079-0}, pages = {58 -- 59}, year = {2016}, abstract = {While plate fixation of proximal ulna fractures might lead to superior clinical results compared to tension band wiring, regular plates represent an established risk factor for wound complications. The olecranon double plates (Medartis, Basel, CH) might decrease complications related to the osteosynthesis because of their low profile and better anatomical fit. This study aimed to evaluate the biomechanical performance and clinical results of the olecranon double plates.}, language = {en} } @article{HacklLeschingerStaatetal.2016, author = {Hackl, Michael and Leschinger, T. and Staat, Manfred and M{\"u}ller, Lars-Peter and Wegmann, Kilian}, title = {Reconstruction of the interosseous membrane in the Essex Lopresti lesion — a biomechanical evaluation}, series = {Knee surgery, sports traumatology, arthroscopy}, volume = {Volume 24}, journal = {Knee surgery, sports traumatology, arthroscopy}, number = {Supplement 1}, publisher = {Springer}, address = {Berlin}, issn = {0942-2056}, doi = {10.1007/s00167-016-4080-7}, pages = {130 -- 131}, year = {2016}, abstract = {Surgical reconstruction of the interosseous membrane (IOM) could restore longitudinal forearm stability to avoid persisting disability due to capituloradial and ulnocarpal impingement in Essex Lopresti lesions. This biomechanical study aimed to assess longitudinal forearm stability of intact specimens, after sectioning of the IOM and after reconstruction with a TightRope construct using either a single or double bundle technique.}, language = {en} } @article{HacklKahmannWegmannetal.2016, author = {Hackl, Michael and Kahmann, Stephanie Lucina and Wegmann, Kilian and Ries, Christian and Staat, Manfred and M{\"u}ller, Lars-Peter}, title = {Shortening osteotomy of the proximal radius — a treatment option for isolated osteoarthritis of the lateral column of the elbow joint?}, series = {Knee surgery, sports traumatology, arthroscopy}, volume = {Volume 24}, journal = {Knee surgery, sports traumatology, arthroscopy}, number = {Supplement 1}, publisher = {Springer}, address = {Berlin}, issn = {0942-2056}, doi = {10.1007/s00167-016-4080-7}, pages = {128 -- 129}, year = {2016}, abstract = {Treatment of posttraumatic osteoarthritis of the radial column of the elbow joint remains a challenging yet common issue. While partial joint replacement leads to high revision rates, radial head excision has shown to severely increase joint instability. Shortening osteotomy of the radius could be an option to decrease the contact pressure of the radiohumeral joint and thereby pain levels without causing valgus instability. Hence, the aim of this biomechanical study was to evaluate the effects of radial shortening on axial load distribution and valgus stability of the elbow joint.}, language = {en} } @article{HacklMuellerStaatetal.2016, author = {Hackl, Michael and M{\"u}ller, Lars-Peter and Staat, Manfred and Kahmann, Stephanie Lucina and Wegmann, Kilian}, title = {Proximal phalangeal neck fractures of the hand — a biomechanical comparison of three fixation techniques}, series = {Knee surgery, sports traumatology, arthroscopy}, volume = {Volume 24}, journal = {Knee surgery, sports traumatology, arthroscopy}, number = {Supplement 1}, publisher = {Springer}, address = {Berlin}, issn = {0942-2056}, doi = {10.1007/s00167-016-4080-7}, pages = {148 -- 149}, year = {2016}, abstract = {Plate osteosynthesis of displaced proximal phalangeal neck fractures of the hand allows early mobilization due to a stable internal fixation. Nevertheless, joint stiffness—because of soft tissue irritation—represents a common complication leading to high complication rates. Del Pinal et al. recently reported promising clinical results for a new, minimally invasive fixation technique with a cannulated headless intramedullary compression screw. Hence, the aim of this study was to compare plate fixation of proximal phalangeal neck fractures to less two less invasive techniques: Crossed k-wire fixation and intramedullary screw fixation. We hypothesized that these fixation techniques provide inferior stability when compared to plate osteosynthesis.}, language = {en} } @book{IomdinaBauerKotliar2015, author = {Iomdina, E. N. and Bauer, S. M. and Kotliar, Konstantin}, title = {БИОМЕХАНИКА ГЛАЗА: ТЕОРЕТИЧЕСКИЕ АСПЕКТЫ И КЛИНИЧЕСКИЕ ПРИЛОЖЕНИЯ}, publisher = {Real Time}, address = {Moscow}, isbn = {978-5-903025-57-2}, pages = {208 Seiten}, year = {2015}, language = {ru} } @inproceedings{KahmannHacklWegmannetal.2016, author = {Kahmann, Stephanie and Hackl, Michael and Wegmann, Kilian and M{\"u}ller, Lars-Peter and Staat, Manfred}, title = {Impact of a proximal radial shortening osteotomy on the distribution of forces and the stability of the elbow}, series = {1st YRA MedTech Symposium 2016 : April 8th / 2016 / University of Duisburg-Essen}, booktitle = {1st YRA MedTech Symposium 2016 : April 8th / 2016 / University of Duisburg-Essen}, editor = {Erni, Daniel}, publisher = {Universit{\"a}t Duisburg-Essen}, address = {Duisburg}, organization = {MedTech Symposium}, doi = {10.17185/duepublico/40821}, pages = {7 -- 8}, year = {2016}, abstract = {The human arm consists of the humerus (upper arm), the medial ulna and the lateral radius (forearm). The joint between the humerus and the ulna is called humeroulnar joint and the joint between the humerus and the radius is called humeroradial joint. Lateral and medial collateral ligaments stabilize the elbow. Statistically, 2.5 out of 10,000 people suffer from radial head fractures [1]. In these fractures the cartilage is often affected. Caused by the injured cartilage, degenerative diseases like posttraumatic arthrosis may occur. The resulting pain and reduced range of motion have an impact on the patient's quality of life. Until now, there has not been a treatment which allows typical loads in daily life activities and offers good long-term results. A new surgical approach was developed with the motivation to reduce the progress of the posttraumatic arthrosis. Here, the radius is shortened by 3 mm in the proximal part [2]. By this means, the load of the radius is intended to be reduced due to a load shift to the ulna. Since the radius is the most important stabilizer of the elbow it has to be confirmed that the stability is not affected. In the first test (Fig. 1 left), pressure distributions within the humeroulnar and humeroradial joints a native and a shortened radius were measured using resistive pressure sensors (I5076 and I5027, Tekscan, USA). The humerus was loaded axially in a tension testing machine (Z010, Zwick Roell, Germany) in 50 N steps up to 400 N. From the humerus the load is transmitted through both the radius and the ulna into the hand which is fixed on the ground. In the second test (Fig. 1 right), the joint stability was investigated using a digital image correlation system to measure the displacement of the ulna. Here, the humerus is fixed with a desired flexion angle and the unconstrained forearm lies on the ground. A rope connects the load actuator with a hook fixed in the ulna. A guide roller is used so that the rope pulls the ulna horizontally when a tensile load is applied. This creates a moment about the elbow joint with a maximum value of 7.5 Nm. Measurements were performed with varying flexion angles (0°, 30°, 60°, 90°, 120°). For both tests and each measurement, seven specimens were used. Student's t-test was employed to determine whether the mean values of the measurements in native specimen and operated specimens differ significantly.}, language = {en} }