The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Eric Rohr - One of the best experts on this subject based on the ideXlab platform.
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Calcaneus range of motion underestimated by markers on running shoe heel
Gait & Posture, 2018Co-Authors: Ryan S Alcantara, Matthieu B. Trudeau, Eric RohrAbstract:Abstract Background The measurement of rearfoot kinematics by placing reflective markers on the shoe heel assumes its motion is identical to the foot’s motion. Studies have compared foot and shoe kinematics during running but with conflicting results. The primary purpose of this study was to compare shoe and Calcaneus three-dimensional range of motion during running. A secondary purpose was to determine the effect of a less rigid heel counter on tibia motion. Research question Do markers placed on the shoe heel accurately represent Calcaneus kinematics during running? Methods Three-dimensional coordinate data were collected on 14 subjects (M/F: 9/5) who ran on an instrumented treadmill at 3.35 m/s under four conditions: modified/intact neutral shoes, and modified/intact support shoes. Shoes were modified by placing holes through the heel to allow for shoe heel and Calcaneus coordinate data to be collected simultaneously via reflective markers on the shoe and on the skin of the heel within the shoe. Calcaneus, shoe heel, and tibia ROM were calculated from 0 to 50% stance phase and compared across shoe conditions. Results Calcaneal frontal plane ROM was significantly greater than neutral and support shoe heel ROM (p Significance Shoe markers significantly underestimated Calcaneus ROM across all planes of motion. These findings suggest Calcaneus kinematics cannot be accurately measured with markers placed solely on the shoe heel. Additionally, the required modifications to the shoe’s heel had no effect on tibia ROM in the transverse plane.
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The Calcaneus adducts more than the shoe's heel during running
Footwear Science, 2017Co-Authors: Matthieu B. Trudeau, Carl Jewell, Eric Rohr, Katina Mira Fischer, Steffen Willwacher, Gert-peter Brueggemann, Joseph HamillAbstract:Only a few studies have measured the movement of the Calcaneus inside the shoe during running, and those that have done so have focused on the frontal plane of motion. This study's objective was to determine the three-dimensional (3D) movement of the Calcaneus inside the shoe during running. A secondary objective was to determine if Calcaneus movement differs between neutral and support shoes. Ten participants ran at 3.5 m/s in two shoes: a neutral and a support shoe. Right rearfoot kinematics were measured using reflective markers affixed to the shoe heel counter and to the skin of the rearfoot inside the shoe. 3D segment angle ranges of motion were calculated and compared across the shoe heel and Calcaneus conditions, and across the two shoe conditions. The movement of the Calcaneus compared to the shoe heel was not different in the frontal plane, but was significantly different in the transverse plane, with the Calcaneus adducting by 4° more than the shoe heel. The Calcaneus also moved significantly mo...
Sharmila Majumdar - One of the best experts on this subject based on the ideXlab platform.
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heterogeneity of trabecular bone structure in the Calcaneus using magnetic resonance imaging
Osteoporosis International, 1998Co-Authors: J C Lin, M Amling, David C Newitt, Kathy Selby, S K Srivastav, G Delling, H K Genant, Sharmila MajumdarAbstract:The purpose of this study was to quantify the heterogeneity in the trabecular bone structure in the Calcaneus. Magnetic resonance (MR) images of the Calcaneus were obtained in the sagittal plane at an in-plane resolution of 195 microns and a slice thickness of 1000 microns in 12 young normal subjects. Regions of interest (ROI) were selected to cover the Calcaneus using a grid of square boxes (10 mm per side). A thresholding technique based on the regional intensity histogram was used to segment the images into trabecular bone and marrow phases and to calculate measures such as apparent trabecular bone area fraction, apparent trabecular spacing, apparent trabecular thickness and apparent trabecular number. Bone mineral density (BMD) of the Calcaneus was assessed using dual-energy X-ray absorptiometry (DXA). Histological sections of three calcanei were also analyzed using transmission light illumination, and the results used to calibrate our computational software. For a relatively narrow inter-subject variation in posterior BMD, a significant inter-subject variation was seen in MRI-derived structural parameters. Furthermore, the spatial heterogeneity of the structural parameters in the posterior region was as high as 40%. Thus, the posterior tuberosity of the Calcaneus, a typical site for BMD and single-point ultrasound assessments, can demonstrate significant regional variation in trabecular bone structure.
Ryan S Alcantara - One of the best experts on this subject based on the ideXlab platform.
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Calcaneus range of motion underestimated by markers on running shoe heel
Gait & Posture, 2018Co-Authors: Ryan S Alcantara, Matthieu B. Trudeau, Eric RohrAbstract:Abstract Background The measurement of rearfoot kinematics by placing reflective markers on the shoe heel assumes its motion is identical to the foot’s motion. Studies have compared foot and shoe kinematics during running but with conflicting results. The primary purpose of this study was to compare shoe and Calcaneus three-dimensional range of motion during running. A secondary purpose was to determine the effect of a less rigid heel counter on tibia motion. Research question Do markers placed on the shoe heel accurately represent Calcaneus kinematics during running? Methods Three-dimensional coordinate data were collected on 14 subjects (M/F: 9/5) who ran on an instrumented treadmill at 3.35 m/s under four conditions: modified/intact neutral shoes, and modified/intact support shoes. Shoes were modified by placing holes through the heel to allow for shoe heel and Calcaneus coordinate data to be collected simultaneously via reflective markers on the shoe and on the skin of the heel within the shoe. Calcaneus, shoe heel, and tibia ROM were calculated from 0 to 50% stance phase and compared across shoe conditions. Results Calcaneal frontal plane ROM was significantly greater than neutral and support shoe heel ROM (p Significance Shoe markers significantly underestimated Calcaneus ROM across all planes of motion. These findings suggest Calcaneus kinematics cannot be accurately measured with markers placed solely on the shoe heel. Additionally, the required modifications to the shoe’s heel had no effect on tibia ROM in the transverse plane.
Matthieu B. Trudeau - One of the best experts on this subject based on the ideXlab platform.
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Calcaneus range of motion underestimated by markers on running shoe heel
Gait & Posture, 2018Co-Authors: Ryan S Alcantara, Matthieu B. Trudeau, Eric RohrAbstract:Abstract Background The measurement of rearfoot kinematics by placing reflective markers on the shoe heel assumes its motion is identical to the foot’s motion. Studies have compared foot and shoe kinematics during running but with conflicting results. The primary purpose of this study was to compare shoe and Calcaneus three-dimensional range of motion during running. A secondary purpose was to determine the effect of a less rigid heel counter on tibia motion. Research question Do markers placed on the shoe heel accurately represent Calcaneus kinematics during running? Methods Three-dimensional coordinate data were collected on 14 subjects (M/F: 9/5) who ran on an instrumented treadmill at 3.35 m/s under four conditions: modified/intact neutral shoes, and modified/intact support shoes. Shoes were modified by placing holes through the heel to allow for shoe heel and Calcaneus coordinate data to be collected simultaneously via reflective markers on the shoe and on the skin of the heel within the shoe. Calcaneus, shoe heel, and tibia ROM were calculated from 0 to 50% stance phase and compared across shoe conditions. Results Calcaneal frontal plane ROM was significantly greater than neutral and support shoe heel ROM (p Significance Shoe markers significantly underestimated Calcaneus ROM across all planes of motion. These findings suggest Calcaneus kinematics cannot be accurately measured with markers placed solely on the shoe heel. Additionally, the required modifications to the shoe’s heel had no effect on tibia ROM in the transverse plane.
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The Calcaneus adducts more than the shoe's heel during running
Footwear Science, 2017Co-Authors: Matthieu B. Trudeau, Carl Jewell, Eric Rohr, Katina Mira Fischer, Steffen Willwacher, Gert-peter Brueggemann, Joseph HamillAbstract:Only a few studies have measured the movement of the Calcaneus inside the shoe during running, and those that have done so have focused on the frontal plane of motion. This study's objective was to determine the three-dimensional (3D) movement of the Calcaneus inside the shoe during running. A secondary objective was to determine if Calcaneus movement differs between neutral and support shoes. Ten participants ran at 3.5 m/s in two shoes: a neutral and a support shoe. Right rearfoot kinematics were measured using reflective markers affixed to the shoe heel counter and to the skin of the rearfoot inside the shoe. 3D segment angle ranges of motion were calculated and compared across the shoe heel and Calcaneus conditions, and across the two shoe conditions. The movement of the Calcaneus compared to the shoe heel was not different in the frontal plane, but was significantly different in the transverse plane, with the Calcaneus adducting by 4° more than the shoe heel. The Calcaneus also moved significantly mo...
Patricia A Kramer - One of the best experts on this subject based on the ideXlab platform.
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radiographic measurements of the talus and Calcaneus in the adult pes planus foot type
American Journal of Physical Anthropology, 2020Co-Authors: David Agoada, Patricia A KramerAbstract:Objective A distinctive feature of the modern human foot is the presence of a medial longitudinal arch when weight-bearing. Although the talus and Calcaneus play a major role in the structure and function of the human foot, the association between the morphology of these bones and longitudinal arch height has not been fully investigated. A better understanding of this relationship may assist in the interpretation of pedal remains of fossil hominins, where features of the foot and ankle morphology have been described as providing evidence for the presence of a longitudinal arch. Methods For this study, weight-bearing radiographs of 103 patients from an urban US Level 1 trauma center, taken as part of a clinical examination for medical evaluation, were selected. These radiographs were classified as to foot type by arch height as defined using the calcaneal inclination angle. From this group, 68 radiographs were suitable for linear and angular measurements of the talus and 74 of the Calcaneus. The relationships between these measurements and arch height were explored using least squared linear regression analysis. Results The results demonstrate that angular measurements of the Calcaneus (particularly those that reflect the relationship of the talar articular facets to each other and the tilt of the calcaneocuboid joint to the longitudinal axis of the Calcaneus) are predictive of arch height (r2 = .29-.44 p ≤ .001). All angular measurements of the talus and all examined linear measurements of both the talus and Calcaneus were not predictive of arch height. Discussion These results suggest that certain angular measurements of the Calcaneus are associated with arch height in the modern human foot. While this information is useful in the interpretation of hominin pedal remains, the relationship of the morphology of these bones, as well as other bones of the foot, to arch height is complex, requiring further investigation.