Does the postural variable affect the determination of balance compensation level in vestibular schwannoma patients?
The slow growth of vestibular schwannoma (VS) leads to a progressive vestibular dysfunction which is compensated by central adaptive mechanisms to minimize the alteration of the gaze and balance control [1,2]. The total unilateral vestibular deafferentation (uVD) consecutive to the VS surgical removal leads to a decompensation of this previously compensated situation. Early after uVD, the balance control has been found to be severely altered and then progressively restored due to de novo implementation of central adaptive mechanisms which could be of vestibular origin [3,4] and from learning mechanisms implying neural stru...
Source: Medical Engineering and Physics - July 4, 2017 Category: Biomedical Engineering Authors: Julien Fr ère, Charles P. Hoffmann, Gérome C. Gauchard, Cécile Parietti-Winkler Tags: Technical note Source Type: research
Development of an instrumented spinal cord surrogate using optical fibers: A feasibility study
Traumatic spinal cord injury (TSCI) occurs at an annual incidence of 10 –60 cases per million inhabitants depending of the country [1]. In the United States, the annual incidence is about 40 cases per million and the prevalence is estimated at 721 per million [1]. TSCI can potentially damage motor and sensory function, leading to a loss of autonomy and a poor quality of life. Burst fractures and fracture dislocations are responsible for respectively 30% and 40% of all TSCI [2]. They are often accompanied by a certain degree of spinal cord canal occlusion due to bone fragment, ligaments or other structure compromising the...
Source: Medical Engineering and Physics - July 4, 2017 Category: Biomedical Engineering Authors: Yann Facchinello, Éric Wagnac, Bora Ung, Yvan Petit, Prabin Pradhan, Louis-Marie Peyrache, Jean-Marc Mac-Thiong Tags: Technical note Source Type: research
Skill assessment in upper limb myoelectric prosthesis users: Validation of a clinically feasible method for characterising upper limb temporal and amplitude variability during the performance of functional tasks
As a result of concerted efforts over recent decades, there have been significant advances in myoelectric prostheses design. The motors used have become smaller and more powerful, cosmetic covers have become more life-like, and, of most note, multi-functional hands, such as the i-Limb (Touch Bionics, Livingston, UK) and Be-Bionic (Steeper, Leeds, UK) have been developed. Yet, prosthesis users are still greatly limited by the available control modalities and lack of sensory feedback from the prosthesis [1]. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - July 3, 2017 Category: Biomedical Engineering Authors: Sibylle B Thies, Laurence PJ Kenney, Mohammad Sobuh, Adam Galpin, Peter Kyberd, Rebecca Stine, Matthew J Major Source Type: research
Validation of a new 2-D technique for radiographic wear measurement of cemented, highly cross-linked polyethylene acetabular cups
Clinical wear of polyethylene (PE) acetabular cups and cup-liners can be measured from radiographic images. Modern 2-D wear measurement systems were originally developed to measure wear of standard ultra-high-molecular-weight polyethylene cups that had a wear rate of 0.1mm to 0.2mm per year. The accuracy and precision of those systems were sufficient to achieve reasonably accurate measurements after the first few years of wear [1,2]. During the past decade, however, manufacturers have been providing highly cross-linked polyethylene (XLPE) cups which wear at a much reduced rate (a few hundredths of a millimetre per year) [3...
Source: Medical Engineering and Physics - July 3, 2017 Category: Biomedical Engineering Authors: Brian Derbyshire, Bilal Barkatali Source Type: research
Design of wearable and wireless multi-parameter monitoring system for evaluating cardiopulmonary function
The 6-minute walking test (6MWT) is the test most commonly used to evaluate exercise capacity and predict functional outcomes in patients with respiratory or heart disease. In 1985, Guyatt et al. [1] and Lipkin et al. [2] first used the 6MWT to measure the exercise capacity of patients with heart disease. The test is also used to assess prognosis and functional impairment in various respiratory diseases [3 –5]. Recently, the 6MWT has also been applied in sports medicine and fitness activities [6]. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - July 3, 2017 Category: Biomedical Engineering Authors: Shih-Hong Li, Bor-Shing Lin, Chen-An Wang, Cheng-Ta Yang, Bor-Shyh Lin Source Type: research
A generalisable methodology for stability assessment of walking aid users
Falls in older adults are a major global health problem as more than 30% of community-dwelling people aged 65 and over fall every year [1], consequences of which range from reduced activity and fear of falling to injuries and death [2]. Moreover, falls are also a matter of great concern for society as a whole: in 2013, for instance, it was estimated that falls cost the UK government over £2.3 billion [3]. Older frail people with an unstable gait are often advised by their clinician to use walking aids, which are designed to help them maintain their balance through an increase in the effective base of support area, and thr...
Source: Medical Engineering and Physics - July 3, 2017 Category: Biomedical Engineering Authors: E. Costamagna, S.B. Thies, L.P.J. Kenney, D. Howard, A. Liu, D. Ogden Source Type: research
Influence of spinal disc translational stiffness on the lumbar spinal loads, ligament forces and trunk muscle forces during upper body inclination
Inverse dynamic musculoskeletal models are frequently used to predict the joints reactions, bending moments and trunk muscle forces for different body movements and postures [1,2]. These findings are helpful in many areas such as work place safety design, ergonomics, injury prevention, performance enhancement, implant design and rehabilitation management. Due to large scale of musculoskeletal multibody models, involving several rigid body segments connected by mechanical joints, including muscle tendon complexes and ligaments, many of the modeling aspects are simplified. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - June 27, 2017 Category: Biomedical Engineering Authors: Rizwan Arshad, Thomas Zander, Maxim Bashkuev, Hendrik Schmidt Source Type: research
Assessment of pose repeatability and specimen repositioning of a robotic joint testing platform
The use of industrial robots is emerging as a powerful tool for studying the load bearing function of ligaments in different human joints. Compared to classical mechanisms, robots offer higher repeatability and can be controlled to apply a given wrench and/or motion to a subject, while recording the resulting motion, forces and torques. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - June 26, 2017 Category: Biomedical Engineering Authors: H. El Daou, B. Lord, A. Amis, F. Rodriguez y Baena Tags: Technical note Source Type: research
Finite-element design and optimization of a three-dimensional tetrahedral porous titanium scaffold for the reconstruction of mandibular defects
Mandible defects usually result from trauma, tumor resection, or osteomyelitis. Unrepaired defects can lead to disturbed masticatory function, loss of speech, and facial deformity, which can seriously affect the patient's quality of life. Thus, timely reconstruction is necessary, but remains a challenge [1]. The goal of mandibular reconstruction is to restore both the shape and function of the mandible. To date, many mandibular reconstruction methods have evolved, such as free bone grafts, pedicled bone grafts, particulate bone cancellous marrow, microvascular free flaps, modular endoprosthesis, and tissue engineered bone ...
Source: Medical Engineering and Physics - June 26, 2017 Category: Biomedical Engineering Authors: Danmei Luo, Qiguo Rong, Quan Chen Source Type: research
Corrigendum to ‘A mathematical method for precisely calculating the radiographic angles of the cup after total hip arthroplasty’ Medical Engineering & Physics 38 (2016) 1376 –1381
The authors would like to apologise for three errors in the above published article. We acknowledge that it is authors ’ responsibility to prevent any mistakes in the manuscript prior to submission and accept full responsibility for those errors. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - June 23, 2017 Category: Biomedical Engineering Authors: Jing-Xin Zhao, Xiu-Yun Su, Ruo-Xiu Xiao, Zhe Zhao, Li-Hai Zhang, Li-Cheng Zhang, Pei-Fu Tang Tags: Corrigendum Source Type: research
Cardiovascular morphometry with high-resolution 3D magnetic resonance: First application to left ventricle diastolic dysfunction
Morphometry, i.e., the analysis of a form or shape with quantitative means, has been applied extensively to explore cardiac and vascular anatomy and function. Examples include the detection of anatomical abnormalities [1], preoperative planning and follow-up of patients with cardiovascular diseases [2 –4], risk prediction associated with atherosclerosis development [5–8], and cardiovascular devices design support [9]. In particular, morphometry-based analysis finds massive adoption for current research of mapping the effects of natural aging on the structural and functional properties of the aorta [10–17]. (Source: M...
Source: Medical Engineering and Physics - June 21, 2017 Category: Biomedical Engineering Authors: Diego Gallo, Orestis Vardoulis, Pierre Monney, Davide Piccini, Panagiotis Antiochos, Juerg Schwitter, Nikolaos Stergiopulos, Umberto Morbiducci Source Type: research
Thermal management in closed incubators: New software for assessing the impact of humidity on the optimal incubator air temperature
Premature and low-birth-weight (LBW) neonates are nursed in closed incubators. Ideally, the air temperature and relative humidity (RH) must enable the maintenance of thermoneutral conditions. Thermoneutrality is defined as the range of air temperatures within which metabolic heat production is minimal and the body temperature can be regulated solely by autonomic and behavioural responses (peripheral vasomotricity, postural changes, etc.) [1,2]. When thermal conditions are outside the thermoneutral zone, the energy needed to maintain body temperature is no longer used for body growth and optimal physiological functioning [1...
Source: Medical Engineering and Physics - June 21, 2017 Category: Biomedical Engineering Authors: St éphane Delanaud, Pauline Decima, Amandine Pelletier, Jean-Pierre Libert, Estelle Durand, Erwan Stephan-Blanchard, Véronique Bach, Pierre Tourneux Source Type: research
The taper corrosion pattern observed for one bi-modular stem design is related to geometry-determined taper mechanics
Total hip replacements with modular necks show an increased risk for early failure [1]. Clinical failures range from neck fracture [2 –6] to symptomatic adverse tissue reactions [7–9]. Early failures of one specific design (Rejuvenate, Stryker Orthopaedics, Mahwah, New Jersey) were linked to fretting-corrosion and substantial wear from the bi-modular neck-piece taper [10–16]. The system was consequently recalled [17]. A rece nt study demonstrated that sections with high local in vivo loads exhibited distinct material loss from the CoCrMo neck pieces [18]. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - June 21, 2017 Category: Biomedical Engineering Authors: Dennis Buente, Michael Bryant, Michael Ward, Anne Neville, Michael Morlock, Gerd Huber Source Type: research
Microwave thermal ablation: Effects of tissue properties variations on predictive models for treatment planning
Microwave thermal ablation (MTA) procedures for the treatment of pathologic tissues rely on the generation of very high temperatures (55 –60°C at minimum) in the target zone owing to the absorption of electromagnetic energy at microwave (MW) frequencies (typically 915MHz or 2.45GHz). At temperatures of about 55–60°C and above, an almost instantaneous cell death is achieved; at lower temperatures coagulation can be induced heati ng the tissue for a longer time, e.g., at 50°C less than 5 min are needed to obtain irreversible cellular injury, whereas at least 60min are needed at 46°C [1,2]. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - June 21, 2017 Category: Biomedical Engineering Authors: Vanni Lopresto, Rosanna Pinto, Laura Farina, Marta Cavagnaro Source Type: research
FE and experimental study on how the cortex material properties of synthetic femurs affect strain levels
Biomechanical experimentation and Finite Element (FE) computer simulation have been major tools for the biomechanical research community in the past few decades [1 –3]. Nevertheless, the reliability of the computational results depends considerably on the accuracy of the material properties, boundary conditions and load applications [4]. Finite element models related to the definitions of bone material properties may be categorized into two groups: micro-fin ite element models and homogenized models [5]. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - June 20, 2017 Category: Biomedical Engineering Authors: Vitor M.M. Lopes, Maria A. Neto, Ana M. Amaro, Luis M. Roseiro, M.F. Paulino Source Type: research
