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Reduction and Fixation of Sacroiliac joint Dislocation by the Combined Use of S1 Pedicle Screws and an Iliac Rod
Published in Kai-Uwe Lewandrowski, Donald L. Wise, Debra J. Trantolo, Michael J. Yaszemski, Augustus A. White, Advances in Spinal Fusion, 2003
Kai-Uwe Lewandrowski, Donald L. Wise, Debra J. Trantolo, Michael J. Yaszemski, Augustus A. White
Dooris investigated the wear characteristics of the Sofamor Danek disc [13] by simultaneously compressing and oscillating the implant ball component over the implant socket component in a saline bath. Periodic mass measurements of the components determined the mass changes. Three wear simulators built by EnduraTec (Stillwater, MN) were utilized to test three implant component pairs (Fig. 7). Given the substantially larger range of motion of the sagittal plane, the implants and system were arranged to provide motion in the sagittal plane. An offset cam on an electric motor was adjusted to rotate the socket component 14.5° (±0.3°) flexion and 4.5° (±0.3°) extension over the ball component. An adjustable pneumatic cylinder applied a static 700 N load (~37 psi) to the socket component in the vertical direction. The mass of each device was determined using a Mettler-Toledo AG 245 (Mettler-Toledo, Switzerland) analytic scale with a precision of ±0.01 mg. Surface replicas from the 500,000 cycles measurement of Socket 5 were sputter-coated with a 100 nm layer of platinum-palladium particles. The sample was then viewed using a Hitachi S5000 scanning electron microscope. Three pairs of artificial disc components were tested to 10 million cycles. Measurements were made every 250,000 cycles to 1.5 million cycles. From 1.5 to 5 million cycles, measurements were made every 500,000 cycles. From 5 to 10 million cycles, measurements were made every 1 million cycles.
Introduction
Published in Eric R. Westervelt, Jessy W. Grizzle, Christine Chevallereau, Jun Ho Choi, Benjamin Morris, Feedback Control of Dynamic Bipedal Robot Locomotion, 2018
Eric R. Westervelt, Jessy W. Grizzle, Christine Chevallereau, Jun Ho Choi, Benjamin Morris
The sagittal plane is the longitudinal plane that divides the body into right and left sections. The frontal plane is the plane parallel to the long axis of the body and perpendicular to the sagittal plane that separates the body into front and back portions. The transverse plane is perpendicular to both the sagittal and frontal planes. See Fig. 1.4 for an illustration of these planes of section. A planar biped is a biped with motions taking place only in the sagittal plane, whereas a three-dimensional walker has motions taking place in both the sagittal and frontal planes.
Imitation jumps in ski jumping: Technical execution and relationship to performance level
Published in Journal of Sports Sciences, 2020
Gertjan Ettema, Steinar Braaten, Jørgen Danielsen, Birk Eirik Fjeld
A motion capture system (Qualisys, Gothenburg, Sweden) with seven Oqus cameras was used for kinematic data collection. To identify body segments and corresponding joints, seven reflective markers (1 cm diameter) were placed unilaterally on the following landmarks: the lateral tip of the acromion (shoulder), the lateral humeral epicondyle (elbow), the ulnar styloid process (wrist), the trochanter major (hip), the lateral femoral epicondyle (knee) and on the surface of the shoe directly over the lateral malleolus (ankle) and the head of the fifth metatarsal (toe). Markers were also placed on the front and rear end of the force plates to identify force plate position to transfer CoP data from local (plate) to the global (Oqus) coordinate system. On basis of these data, ankle, knee, hip, shoulder and elbow angle and – velocity in the sagittal plane were obtained. The included joint angles are reported. Segment angles (leg, thigh, trunk, arm and forearm) were calculated relative to the horizontal. Increase of these angles were defined as positive (leading to positive velocity). Prior to data collection, the force plates of the skis were calibrated using a regular force plate (Kistler 9286AA, Kistler Instruments, Winterthur, Switzerland), both with static forces and by performing imitation ski jumps using the same roller skis with wheels removed from the force plate. The difference in vertical force was less than 1% and CoP in fore-aft direction differed less than 0.003 m. Vertical force measurements were synchronized with 3D motion capture using the Qualisys software. Sample rate was 200 Hz for all variables.
A standalone computing system to classify human foot movements using machine learning techniques for ankle-foot prosthesis control
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Anatomical reference planes consist of 3-imaginary cardinal planes that divide the mass of a body into 3-dimensions. First, the sagittal plane splits the body vertically into left and right halves of equal mass. Second, the frontal plane divides the body vertically into front and back halves. Finally, the horizontal plane separates the body into top and bottom halves (Hall and Lysell 1995). Ankle joint consists of the tibia, fibula, and underlying tarsal bones. The ankle permits the foot for the following movements: dorsiflexion, plantarflexion, inversion, eversion, medial rotation, and lateral rotation. Figure 1 shows these foot movements along with 3- reference planes. It also indicates the below-knee muscles sites for the sensor placement.