Question

at which point the arm rotates ?​

Answer 1

Answer:

At the elbow joint, where the humerus and ulna articulate, the resulting rotation occurs primarily about a fixed point, referred to as the center of rotation. In the case of the elbow joint, this center of rotation is relatively constant throughout the joint range of motion.

Answer 2

Internal (medial) rotation represents the movement of the humerus when an arm flexed to 90° at the elbow isrotated around the longitudinal plane of the humerus such that the hand moves towards the midline of the body.

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