Final answer:
Lateral rotation is the outward rotation of a limb at ball-and-socket joints like the shoulder or hip, moving the front of the limb away from the body's midline.
Step-by-step explanation:
Lateral rotation, also known as external rotation, is a movement at ball-and-socket joints such as the shoulder and hip where a limb is rotated around its long axis, moving the anterior surface of the limb away from the midline of the body. This action is contrasted with medial (internal) rotation, where the anterior surface moves toward the midline. For instance, when performing lateral rotation, the humerus (upper arm bone) or femur (thigh bone), which are classified as long bones, rotate outward at their respective joints.
The ability to perform lateral rotation is crucial for various daily activities and athletic movements. This type of rotation enables the main actions and postures required in many sports and forms an integral part of joint mobility and overall skeletal function.