b) The term “flexion” refers bending of a joint muscle, “semiflexion” means half of the bending, while “dorsiflexion” may mean_________.
举一反三
- Read the following passage and then do the exercises (multiple choice) given below. Classification of Muscle Actions It is useful to be able to describe the effect of muscle contraction on a joint in terms which may be applied throughout the body and which are related to the anatomical position. The descriptive terms express very poorly, however, the complexities of movement, since they resolve movement to arbitrary planes of action. Flexion is the term used to describe the bending of a pan or the making of an angle, most easily visualized in the bending of the elbow or the knee. The opposite term extension fundamentally means a straightening. In the anatomical position most of the members of the body are in the extended position; the arms and legs are straight, as is also the back. In the case of the foot, these terms lead to some confusion since, in the erect position, the ankle is almost continuously semiflexed. From this position, further flexion is more readily understood under the term dorsiflexion and extension under the term plantar flexion. Plantar flexion is obviously bending in the direction of the sole; dorsiflexion, bending in the direction of the dorsum. For movement away from or toward the central axis of the body the terms abduction and adduction are applied. These terms lead to no confusion except in the hands and feel where there is movement of the digits away from and toward a plane wholly within these parts. Rotational movement is also recognized. Rotation of the anterior surface of a member toward the midplane of the body is medial rotation; rotation away from the midplane is lateral rotation. The rotary action of the forearm and hand, which can he readily observed as the hand is turned palm up or palm down, has a special designation. Pronation is rotation so as to turn the palm downward or backward; supination carries the palm upward or forward. There is a similar though less extensive movement of the foot in which rotation takes place in tile tarsal joints. The rotation of the foot so that the sole turns outward is eversion; the opposite movement so that the sole turns inward is inversion. A special case of rotation is that which is seen in the very important opposing action of the thumb. This movement of rolling the thumb over onto the hand so that the pads of the digits converge into a firm grasp is termed opposition; it is exhibited to a lesser degree in the little finger and in the great and small toes. Circumduction is circular movement; to produce this type of motion, flexion and extension, abduction and adduction are combined in a proper sequence. Special terms, such as protrusion and retraction, elevation and depression, will be referred to in their proper context but are relatively self-evident. a)Muscle actions in various patterns, have been mentioned this passage except________.
- The distribution bending moment in the moment distribution method is equal to: A: Fixed end bending moment B: Distal bending moment C: The inverse of the unbalanced moment is multiplied by the distribution coefficient D: Multiplying the bending moment of the fixed end by the distribution coefficient
- An axial compressive force F＝Fcr is acting on an ideal column in linear equilibrium. And then the column produces the bending deformation due to a small lateral disturbing force. If the disturbing force is removed at this time, ( ) . A: The bending deformation will disappear and return to a straight line B: The bending deformation is reduced and the straight line shape can not be restored C: The bending state is not changed D: The bending deformation continues to increase
- When calculating the displacement of composite structure: A: Only bending moment is considered B: Only axial force is considered C: Bending moment and shear force are considered D: Bending moment and axial force are considered
- Bending in a main plane is called（）