Spatiotemporal gait parameters are commonly used to quantify physical functioning including in populations with atypical foot strike patterns. The current gold standard measurement system for gait analysis is marker-based motion capture and floor-mounted force plates, but it can be expensive and cumbersome to set up. Pressure sensitive walkways are more affordable, quicker to set up, and more portable.
View Article and Find Full Text PDFAs perturbation training is gaining popularity, it is important to better understand postural control during complex three-dimensional stimuli. One clinically relevant and commonly used three-dimensional stimulus is found in hippotherapy and simulated hippotherapy on a mechanical horse. We tested nine healthy participants on a horse simulator, measured head and trunk kinematics, and characterized data in time (root-mean-square and variability) and frequency (amplitude spectra, gains, and phases) domains.
View Article and Find Full Text PDFA prevailing rationale for equine assisted therapies is that the motion of a horse can provide sensory stimulus and movement patterns that mimic those of natural human activities such as walking. The purpose of this study was to quantitatively measure and compare human pelvis motions when walking to those when riding a horse. Six able-bodied children (inexperienced riders, 8-12years old) participated in over-ground trials of self-paced walking and leader-paced riding on four different horses.
View Article and Find Full Text PDFResidual force enhancement (RFE) is a term describing the observation that muscle tension during a contraction that includes a stretch and hold remains above that during an isometric contraction at the hold length. RFE has been observed during in vitro and in vivo experiments, but results involving voluntary contractions are mixed, particularly with respect to large muscles. The purpose of this study was to determine if RFE can be observed in large muscles such as knee extensors and flexors at joint configurations corresponding to the ascending and descending limbs of the muscle force-length curve.
View Article and Find Full Text PDFObjectives: To describe the acceptance and refusal rates of travel-related vaccine and medication recommendations in a pharmacist-run travel health clinic, to evaluate the change in patient understanding of travel-related issues, to determine patient satisfaction with this clinic, and to determine factors influencing both patient acceptance and satisfaction.
Setting: Southern California (Claremont) between July 2007 and October 2008.
Practice Description: Hendricks Pharmacy is an independently owned community pharmacy that is part of the Good Neighbor Pharmacy Provider Network.
Background: Shoulder girdle muscles are important for stabilizing the scapula and orienting the glenoid for upper-extremity motion. However, data describing shoulder girdle strength and how it varies with position is lacking.
Methods: A series of experiments was conducted to measure isometric strength at three positions each for elevation, depression, protraction, and retraction of the shoulder girdle.
The purpose of this study was to develop and apply a general method for estimating the architectural properties of human muscles in vivo. The method consists of a two-phase, nested optimization procedure in which the values of peak isometric force, optimal muscle-fiber length, and tendon slack length are calculated for each musculotendon actuator, knowing muscle volume and the minimum and maximum physiological lengths of the actuator. In phase I, the positions of the bones and the activation levels of the muscles are found by maximizing the isometric torque developed for each degree of freedom at each joint.
View Article and Find Full Text PDFComput Methods Biomech Biomed Engin
January 2000
A computational method is introduced for modeling the paths of muscles in the human body. The method is based on the premise that the resultant muscle force acts along the locus of the transverse cross-sectional centroids of the muscle. The path of the muscle is calculated by idealizing its centroid path as a frictionless elastic band, which moves freely over neighboring anatomical constraints such as bones and other muscles.
View Article and Find Full Text PDFComput Methods Biomech Biomed Engin
January 1999
A kinematic model of the arm was developed using high-resolution medical images obtained from the National Library of Medicine's Visible Human Project (VHP) dataset. The model includes seven joints and uses thirteen degrees of freedom to describe the relative movements of seven upper-extremity bones: the clavicle, scapula, humerus, ulna, radius, carpal bones, and hand. Two holonomic constraints were used to model the articulation between the scapula and the thorax.
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