Final answer:
Horizontal abduction refers to the lateral movement of the arm away from the body in the transverse plane, typically ranging from 0 to 45 degrees.
Step-by-step explanation:
The normal range for horizontal abduction of the shoulder is typically considered to be from 0 to 45 degrees. During horizontal abduction, the arm moves laterally away from the body while in a transverse plane, parallel to the ground, after being in a position of horizontal adduction which closes the arm across the chest.
This movement is distinct from abduction in the coronal plane, which moves the limb away from the midline of the body in an upward direction. The specific range of motion may vary slightly among individuals depending on factors such as flexibility, joint structure, and muscle development.