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Introduction
Published in J. Terrence Jose Jerome, Clinical Examination of the Hand, 2022
The metacarpal base articulates with the distal carpal row (trapezium on the lateral to hamate on the ulnar side). The distal carpal row articulates with the proximal carpal row bones. This proximal carpal row gives wrist flexion, extension, radial deviation and ulnar deviation movements (Figure 1.10). The proximal carpal row articulates with the radius and ulna to form an inferior (distal) radioulnar joint. It is a uniaxial pivot joint providing pronation and supination (Figure 1.11). Interestingly, the wrist has three axes of movement, allowing the hand to be positioned in any spatial configuration and enabling it to be placed as needed for grip, prehensile and grasping [5].
Actions of Dopamine on the Skin and the Skeleton
Published in Nira Ben-Jonathan, Dopamine, 2020
The adult human body contains 206 bones and approximately 300 joints, defined as points where two bones meet. Several types of joints are recognized. Synovial joints are found in arms and legs and enable bones to move over each other. Cartilaginous joints, such as those found in the spine and pelvis, provide more stability and less movement. Fibrous joints, as found in the skull, offer stability but do not allow movement at all in the adult. The joints between bones allow movement, with some allowing a wider range of movement than others, e.g., the ball and socket joint of the shoulder allows a greater range of movement than the pivot joint at the neck. Movement is powered by skeletal muscles, which are attached to the skeleton at various sites on bones.
Fundamentals
Published in Clare E. Milner, Functional Anatomy for Sport and Exercise, 2019
A pivot (trochoidal) joint is a special type of uniaxial joint. In this case, a bone with a rounded end is encircled by a ring formed from the second bone and its ligament: rotation is possible about the long axis of the encircled bone only. Pivot joints in the body are the proximal radioulnar and atlantoaxial joints.
Study of flapping wings to identify best performance conditions
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2019
D. Diaz, L. David, F. Pons, T. Jardin, N. Gourdain
The experimental tests were performed in a water tank made of Altuglas with an octagonal section and dimensions of 1 m × 1 m × 1.5 m. The different wings are attached at their root by a pivot joint, allowing the rotation along the spanwise axis. This enables the modification of the angle of attack (α). At the same time, the pivot joint is fixed into a vertical axis that allows the revolving motion (ψ) in a horizontal plane. The flapping motion to mimic corresponds to a wing with a NACA0012 profile with a 1 cm chord and 4 cm span flapping in the air at a Reynolds number of 1,000 and a frequency of 10.18 Hz. At the start (ψ = −60°) or end (ψ = 60°) of the upstroke/downstroke, the wing is subjected to both rotating and acceleratingdecelerating phases. After the supination or pronation, the airfoil undergoes a constant velocity revolution phase with a fixed angle of attack. This same configuration was used in Diaz et al. (2018), as well as the procedure for the PIV acquisition.