Abstract:
:Spinal cord injury patients are under daily risk for developing deep tissue injury which is a severe pressure ulcer that initiates in soft tissues at the bones' proximity. We aimed to formulate a patient-specific biomechanical model that can continuously monitor internal tissue stresses in real time. We adopted a formulation solving an axisymmetric contact problem of a finite-thickness, elastic layer (soft tissue), and a rigid spherical indentor (ischial tuberosity). We utilized finite element analyses to expand the formulation for large deformations. Sensitivity analyses showed that the soft tissue mechanical properties are the most influential factors in this modeling. We then used synthetic surface pressure data and actual surface pressures recorded under the buttocks of five paraplegic wheelchair users to demonstrate clinical feasibility. Output parameters were designed to be simple so that they can be easily interpreted by the user. Specifically, we calculated peak and average internal von Mises stress and stress dose, under each buttock, and also a time-dependent stress asymmetry index, to account for frequency of posture adjustments. Inter-subject variability was higher than the intra-subject variability. The heaviest subject had the highest maximal and average peak internal soft tissue stress. We believe that this method holds a high potential for clinical applications.
journal_name
Med Biol Eng Computjournal_title
Medical & biological engineering & computingauthors
Portnoy S,Vuillerme N,Payan Y,Gefen Adoi
10.1007/s11517-011-0754-ysubject
Has Abstractpub_date
2011-04-01 00:00:00pages
473-83issue
4eissn
0140-0118issn
1741-0444journal_volume
49pub_type
杂志文章abstract::The purpose of this study was to evaluate the effect of increased blood flow on angiogenesis at the large vessels. The arteriovenous (AV) shunt was made on the thigh of male Wistar rats (n = 27) to increase blood flow, wrapped with artificial skin dermis, which consisted of a silicon outer layer, and isolated from sur...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02345133
更新日期:2005-01-01 00:00:00
abstract::The vagus nerves convey both afferent and efferent information about autonomic activity related to cardiovascular functions. Those functions have been shown to change due to epileptic seizures, which suggests that ictal events might be detected via the vagus electroneurogram (VENG). In this study, we characterize the ...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-011-0782-7
更新日期:2011-09-01 00:00:00
abstract::This work addresses the problem of estimating the conduction velocity (CV) of single motor unit (MU) action potentials from surface EMG signals detected with linear electrode arrays during voluntary muscle contractions. In ideal conditions, that is without shape or scale changes of the propagating signals and with add...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02344807
更新日期:2001-03-01 00:00:00
abstract::Fluctuation analysis has great potential to contribute to pulmonary clinical science and practice. We evaluated the relationship between asthma and the respiratory impedance recurrence period density entropy (RPDEnZrs) and the variability (SDZrs). A non-invasive and simple protocol for assessing respiratory mechanics ...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-012-0957-x
更新日期:2012-12-01 00:00:00
abstract::Pain control in conscious patients was investigated using a push-button, demand-driven supply of drugs. A fuzzy logic patient-controlled analgesia (PCA) algorithm was compared with a conventional algorithm, for alfentanil administration in extracorporeal shock-wave lithotripsy. The conventional PCA algorithm used an i...
journal_title:Medical & biological engineering & computing
pub_type: 临床试验,杂志文章
doi:10.1007/BF02347706
更新日期:2002-01-01 00:00:00
abstract::Marfan syndrome (MFS) is a genetic disorder that affects connective tissue, impairing cardiovascular structures and function, such as heart valves and aorta. Thus, patients with Marfan disease have a higher risk of developing circulatory problems associated with mitral and aortic valves prolapse, manifested as dilated...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-016-1524-7
更新日期:2017-03-01 00:00:00
abstract::In vivo follow-up of muscle shape variation represents a challenge when evaluating muscle development due to disease or treatment. Recent developments in muscles reconstruction techniques indicate MRI as a clinical tool for the follow-up of the thigh muscles. The comparison of 3D muscles shape from two different seque...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-015-1302-y
更新日期:2015-10-01 00:00:00
abstract::This study introduced the Kalman filter procedure for tracking urinary bladder filling from intermittent bladder volume measurements taken by an ultrasonic bladder volume monitor. The Kalman filter was based on a double integrator as a model for the bladder filling process between micturitions and included a procedure...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02345809
更新日期:2005-05-01 00:00:00
abstract::The objective of this study was to evaluate the effect of following combined treatment with parathyroid hormone (1-34) (PTH) and beta-tricalcium phosphate (β-TCP) on local bone formation in a rat 3-mm critical-size defect at distal femur. Twelve weeks after bilateral ovariectomy (OVX) and sham operation (sham), all an...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-015-1402-8
更新日期:2016-09-01 00:00:00
abstract::Smoothing and differentiation of noisy signals are common problems whenever it is difficult or impossible to obtain derivatives by direct measurement. In biomechanics body displacements are frequently assessed and these measurements are affected by noise. To avoid high-frequency noise magnification, data filtering bef...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02441963
更新日期:1990-09-01 00:00:00
abstract::An eye pointer was developed as a new line-of-sight displacement analyser. It analyses an observer's eye movements and superimposes their line of vision on a TV image which is the same as their view. A newly developed miniature colour field camera and very compact eye-movement sensors are attached to a translucent rei...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02446149
更新日期:1990-07-01 00:00:00
abstract::Osteoporosis is one of the most common diseases that leads to bone fractures. Dual-energy X-ray absorptiometry is currently employed to measure the bone mineral density and to diagnose osteoporosis. Alternatively, the dielectric properties of bones are found to be influenced by bone mineral density; hence, dielectric ...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章,评审
doi:10.1007/s11517-018-1887-z
更新日期:2019-01-01 00:00:00
abstract::Chronic obstructive pulmonary disease (COPD) is characterized by expiratory airflow limitation, but current diagnostic criteria only consider flow till the first second and are therefore strongly debated. We aimed to develop a data-based individualized model for flow decline and to explore the relationship between mod...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-014-1202-6
更新日期:2014-12-01 00:00:00
abstract::During dialysis the ion concentrations in many body fluids change significantly. The influence of these changes on the accuracy of volume measurements with bioimpedance spectroscopy is investigated by the following procedure: Plasma ion concentrations and impedance spectra (5-500 kHz) are measured during six standard ...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02534137
更新日期:1997-03-01 00:00:00
abstract::This review is a commentary on recent, altered perspectives about biomedical engineering and its role in medicine. It is argued that, rather than being a peripheral specialty, medical engineering and engineering principles in general have a direct application to biochemical medicine and cell biology. A brief descripti...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章,评审
doi:10.1007/BF02446170
更新日期:1992-07-01 00:00:00
abstract::A method for accurately finding cardiac bidomain conductivity parameters is a crucial part of efforts to study and understand the electrical functioning of the heart. The bidomain model considers current flowing along (longitudinal) and across (transverse) sheets of cardiac fibres, as well as between these sheets (nor...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-013-1101-2
更新日期:2013-12-01 00:00:00
abstract::Tissue hardness is related to tissue composition, and this is often changed by disease. It is therefore of interest to measure the hardness in an objective and non-invasive way. A tactile sensor based on a vibrating piezoelectric ceramic element in a feedback loop is described. When the sensor touches an object it pro...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02513357
更新日期:1999-09-01 00:00:00
abstract::The paper describes an investigation in which it is shown that small positive voltage pulses applied to an external conductor placed against the photocathode of a photomultiplier tube can be used to switch the photocathode completely off for the duration of the pulses. This suggests that a photomultiplier tube with a ...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02441486
更新日期:1989-05-01 00:00:00
abstract::In electrocardiographic imaging (ECGI), one solves the inverse problem of electrocardiography (ECG) to reconstruct equivalent cardiac sources based on the body surface potential measurements and a mathematical model of the torso. Due to attenuation and spatial smoothing within the torso, this inverse problem is ill-po...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-019-02018-6
更新日期:2019-10-01 00:00:00
abstract::Divided attention is defined as focusing on different tasks at once, and this is described as one of the biggest problems of today's society. Default examinations for understanding attention are questionnaires or physiological signals, like evoked potentials and electroencephalography. Physiological records were obtai...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-019-02013-x
更新日期:2019-09-01 00:00:00
abstract::It is clinically well-established that minimally invasive subcutaneous continuous glucose monitoring (CGM) sensors can significantly improve diabetes treatment. However, CGM readings are still not as reliable as those provided by standard fingerprick blood glucose (BG) meters. In addition to unavoidable random measure...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-014-1226-y
更新日期:2015-12-01 00:00:00
abstract::The changes in the power spectra of single-fibre extracellular action potentials (SFEAPs) generated in an infinite anisotropic frequency-dependent volume conductor, which occurred as a result of alterations in the propagation velocity v and duration T(in) of the intracellular action potential (IAP) were analytically d...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02446167
更新日期:1992-07-01 00:00:00
abstract::The relation is investigated between stimulus frequency, stimulus pulse amplitude and the neural damage induced by continuous stimulation of the cat's sciatic nerve. The chronically implanted electrodes were pulsed continuously and the effects of the electrical stimulation were quantified as the amount of early axonal...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02510526
更新日期:1995-05-01 00:00:00
abstract::In this study, we propose an integrated tooth segmentation and gingival tissue deformation simulation framework used to design and evaluate the orthodontic treatment plan especially with invisible aligners. Firstly, the bio-characteristics information of the digital impression is analyzed quantitatively and demonstrat...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-020-02230-9
更新日期:2020-10-01 00:00:00
abstract::To elucidate the mechanisms of localisation of intimal hyperplasia in anastomosed arteries, the effects of flow disturbances on the transport of low-density lipoproteins (LDLs) from the flowing blood to the wall of end-to-end anastomosed arteries, with and without a moderate stenosis, were studied theoretically by mea...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02345458
更新日期:2002-09-01 00:00:00
abstract::In this study, we present finite element analysis models to calculate the increase in intrathoracic volume of pectus excavatum patients after the Nuss procedure. One virtue of our approach is that the measurement of the intrathoracic volume has no time difference and is not affected by postoperative pain, which cannot...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-009-0570-9
更新日期:2010-02-01 00:00:00
abstract::Tooth mobility examination is important in planning dental treatment, as it may give an indication of alveolar bone loss and the condition of the periodontal ligament. In clinical dental diagnosis a manual tooth mobility examination is useful. However, its determination of tooth mobility is subjective and depends on t...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02442173
更新日期:1989-01-01 00:00:00
abstract::Transurethral resection of the prostate is the most common method of relieving urinary outflow obstruction secondary to prostatic enlargement. However, this procedure can be responsible for various complications, including irrigant-fluid absorption and blood loss, both of which are strongly dependent on operation dura...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02510962
更新日期:1997-11-01 00:00:00
abstract::In daily life, a person's gait-an important marker for his/her health status-is usually assessed using inertial sensors fixed to lower limbs or trunk. Such sensor locations are not well suited for continuous and long duration measurements. A better location would be the wrist but with the drawback of the presence of p...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/s11517-017-1621-2
更新日期:2017-10-01 00:00:00
abstract::The regulation of cerebral blood flow (CBF) following changes in arterial blood pressure (ABP) and end-tidal pCO2 (EtCO2) are of clinical interest in assessing cerebrovascular reserve capacity. Linear finite-impulse-response modelling is applied to ABP, EtCO2 and CBF velocity (CBFV, from transcranial Doppler measureme...
journal_title:Medical & biological engineering & computing
pub_type: 杂志文章
doi:10.1007/BF02345749
更新日期:2000-09-01 00:00:00