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Editorial

Herder, J.L. (author), Barrari, A. (author), Tolou, N. (author)

Yet another journal? And what is the windmill about? Those are two questions that we heard a lot lately. Yes, another journal, or rather, a different journal, called Mechanical Sciences (MS). The main difference is that the journal is open access, of which there are not many in the field of mechanical sciences. Grant agencies more and more...

journal article 2010

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Relating reflex gain modulation in posture control to underlying neural network properties using a neuromusculoskeletal model

Schuurmans, J. (author), Van der Helm, F.C.T. (author), Schouten, A.C. (author)

During posture control, reflexive feedback allows humans to efficiently compensate for unpredictable mechanical disturbances. Although reflexes are involuntary, humans can adapt their reflexive settings to the characteristics of the disturbances. Reflex modulation is commonly studied by determining reflex gains: a set of parameters that quantify...

journal article 2010

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Feasibility of noncontact piezoelectric detection of photoacoustic signals in tissue-mimicking phantoms

Kolkman, R.G.M. (author), Blomme, E. (author), Cool, T. (author), Bilcke, M. (author), Van Leeuwen, T.G. (author), Steenbergen, W. (author), Grimbergen, K.A. (author), Den Heeten, G.J. (author)

The feasibility of air-coupled ultrasound transducers to detect laser-induced ultrasound from artificial blood vessels embedded in an optically scattering phantom is demonstrated. These air-coupled transducers allow new applications in biomedical photoacoustic imaging where contact with tissue is not preferred. One promising application of such...

journal article 2010

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Probing forces of menisci: What levels are safe for arthroscopic surgery

Tuijthof, G.J.M. (author), Horeman, T. (author), Schafroth, M.U. (author), Blankevoort, L. (author), Kerkhoffs, G.M.M.J. (author)

Purpose To facilitate effective learning, feedback on performance during arthroscopic training is essential. Less attention has been paid to feedback on monitoring safe handling of delicate tissues such as meniscus. The goal is to measure in vitro probing forces of menisci and compare them with a theoretical maximum probing force (TMPF). Method...

journal article 2010

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The relation between neuromechanical parameters and Ashworth score in stroke patients

De Vlugt, E. (author), De Groot, J.H. (author), Schenkeveld, K.E. (author), Arendzen, J.H. (author), Van der Helm, F.C.T. (author), Meskers, C.G.M. (author)

Quantifying increased joint resistance into its contributing factors i.e. stiffness and viscosity ("hypertonia") and stretch reflexes ("hyperreflexia") is important in stroke rehabilitation. Existing clinical tests, such as the Ashworth Score, do not permit discrimination between underlying tissue and reflexive (neural) properties. We propose an...

journal article 2010

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Vacuum packed particles as flexible endoscope guides with controllable rigidity

Loeve, A.J. (author), Van de Ven, O.S. (author), Vogel, J.G. (author), Breedveld, P. (author), Dankelmann, J. (author)

In order to fully benefit from the functionalities of flexible endoscopes in surgery a simple shaft-guide that can be used to support the flexible endoscope shaft is required. Such a shaft-guide must be flexible during insertion into the human body and rigidified when properly positioned to support the flexible endoscope shaft. A shaft-guide...

journal article 2010

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Design, fabrication, and preliminary results of a novel below knee prosthesis for snowboarding: A case report

Minnoye, A.L.M. (author), Plettenburg, D.H. (author)

Snowboarding with a below-knee prosthesis is compromised by the limited rotation capabilities of the existing below-knee prostheses, which are designed for use in normal walking. Based on snowboarding range of motion analyses, a novel below-knee prosthesis was designed with the aim to achieve similar range of motions like able-bodied...

journal article 2010

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Force measurement platform for training and assessment of laparoscopic skills

Horeman, T. (author), Rodrigues, S.P. (author), Jansen, F.W. (author), Dankelman, J. (author), Van den Dobbelsteen, J.J. (author)

Background - To improve endoscopic surgical skills, an increasing number of surgical residents practice on box or virtual-reality (VR) trainers. Current training is mainly focused on hand–eye coordination. Training methods that focus on applying the right amount of force are not yet available. Methods - The aim of this project is to develop a...

journal article 2010

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Intrinsically Safe Robot Arm: Adjustable Static Balancing and Low Power Actuation

Vermeulen, M. (author), Wisse, M. (author)

We present a design for a manipulator that is intrinsically mechanically safe, i.e. it can not cause pain (let alone damage) to a human being even if the control system has a failure. Based on the pressure pain thresholds for human skin, we derive a pinching safety constraint that limits the actuator torque, and an impact safety constraint that...

journal article 2010

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An explorative, cross-sectional study into abnormal muscular coupling during reach in chronic stroke patients

Prange, G.B. (author), Jannink, M.J.A. (author), Stienen, A.H.A. (author), Van der Kooij, H. (author), IJzerman, M.J. (author), Hermens, H.J. (author)

Background: In many stroke patients arm function is limited, which can be related to an abnormal coupling between shoulder and elbow joints. The extent to which this can be translated to activities of daily life (ADL), in terms of muscle activation during ADL-like movements, is rather unknown. Therefore, the present study examined the occurrence...

journal article 2010

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Recycling Energy to Restore Impaired Ankle Function during Human Walking

Collins, S.H. (author), Kuo, A.D. (author)

Background: Humans normally dissipate significant energy during walking, largely at the transitions between steps. The ankle then acts to restore energy during push-off, which may be the reason that ankle impairment nearly always leads to poorer walking economy. The replacement of lost energy is necessary for steady gait, in which mechanical...

journal article 2010

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The intermuscular 3–7 Hz drive is not affected by distal proprioceptive input in myoclonus-dystonia

Van der Meer, J.N. (author), Schouten, A.C. (author), Bour, L.J. (author), De Vlugt, E. (author), Van Rootselaar, A.F. (author), Van der Helm, F.C.T. (author), Tijssen, M.A.J. (author)

In dystonia, both sensory malfunctioning and an abnormal intermuscular low-frequency drive of 3–7 Hz have been found, although cause and eVect are unknown. It is hypothesized that sensory processing is primarily disturbed and induces this drive. Accordingly, experimenter-controlled sensory input should be able to inXuence the frequency of the...

journal article 2010

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An Isolator System for minimally invasive surgery: The new design

Horeman, T. (author), Jansen, F.W. (author), Dankelman, J. (author)

Background - The risk of obtaining a postsurgical infection depends highly on the air quality surrounding the exposed tissue, surgical instruments, and materials. Many isolators for open surgery have been invented to create a contained sterile volume around the exposed tissue. With the use of an isolator, a surgical procedure can be performed...

journal article 2010

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Discovery of high-level tasks in the operating room

Bouarfa, L. (author), Jonker, P.P. (author), Dankelman, J. (author)

Recognizing and understanding surgical high-level tasks from sensor readings is important for surgical workflow analysis. Surgical high-level task recognition is also a challenging task in ubiquitous computing because of the inherent uncertainty of sensor data and the complexity of the operating room environment. In this paper, we present a...

journal article 2010

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Five-point Likert items: t test versus Mann-Whitney-Wilcoxon

de Winter, J.C.F. (author), Dodou, D. (author)

journal article 2010

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Tizanidine does not affect the linear relation of stretch duration to the long latency M2 response of m. flexor carpi radialis

Meskers, C.G.M. (author), Schouten, A.C. (author), Rich, M.M.L. (author), De Groot, J.H. (author), Schuurmans, J. (author), Arendzen, J.H. (author)

The long latency M2 electromyographic response of a suddenly stretched active muscle is stretch duration dependent of which the nature is unclear. We investigated the inXuence of the group II aVerent blocker tizanidine on M2 response characteristics of the m. Xexor carpi radialis (FCR). M2 response magnitude and eliciting probability in a group...

journal article 2009

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Augmented Reality for Art, Design and Cultural Heritage: System Design and Evaluation

Caarls, J. (author), Jonker, P. (author), Kolstee, Y. (author), Rotteveel, J. (author), Van Eck, W. (author)

This paper describes the design of an optical see-through head-mounted display (HMD) system for Augmented Reality (AR). Our goals were to make virtual objects “perfectly” indistinguishable from real objects, wherever the user roams, and to find out to which extent imperfections are hindering applications in art and design. For AR, fast and...

journal article 2009

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Objective classification of residents based on their psychomotor laparoscopic skills

Chmarra, M.K. (author), Klein, S. (author), De Winter, J.C.F. (author), Jansen, F.W. (author), Dankelman, J. (author)

Background - From the clinical point of view, it is important to recognize residents’ level of expertise with regard to basic psychomotor skills. For that reason, surgeons and surgical organizations (e.g., Acreditation Council for Graduate Medical Education, ACGME) are calling for assessment tools that credential residents as technically...

journal article 2009

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A rigorous model of reflex function indicates that position and force feedback are flexibly tuned to position and force tasks

Mugge, W. (author), Abbink, D.A. (author), Schouten, A.C. (author), Dewald, J.P.A. (author), Van der Helm, F.C.T. (author)

This study aims to quantify the separate contributions of muscle force feedback, muscle spindle activity and co-contraction to the performance of voluntary tasks (‘‘reduce the influence of perturbations on maintained force or position’’). Most human motion control studies either isolate only one contributor, or assume that relevant reflexive...

journal article 2009

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The videolaryngoscope is less traumatic than the classic laryngoscope for a difficult airway in an obese patient

Maassen, R. (author), Lee, R. (author), Van Zundert, A. (author), Cooper, R. (author)

This report describes the anesthetic management of an obese patient with a difficult airway and the merits of videolaryngoscopy, specifically in terms of the reduced risk of dental damage during intubation. A 49-year-old woman (body mass index; BMI, 36 kg·m?2), was scheduled to undergo an elective laparoscopic cholecystectomy because of...

journal article 2009