Radius (bone) in the grooves on the lower end of the bone. The lateral surface ("facies lateralis; external surface") is convex throughout its entire extent and is known as the convexity of the radius, curving outwards to be convex at the side. Its upper third gives insertion to the supinator muscle. About its center is a rough ridge, for the insertion of the pronator teres muscle. Its lower part is narrow, and covered by the tendons of the abductor pollicis longus muscle and extensor pollicis brevis muscle. The upper extremity of the radius (or proximal extremity) presents a head, neck, and tuberosity.
Sternocleidomastoid muscle result from birth trauma that gives rise to a mass or tumor that can be palpated within the muscle. It is given the name "sternocleidomastoid" because it originates at the manubrium of the sternum ("sterno-") and the clavicle ("cleido-"), and has an insertion at the mastoid process of the temporal bone of the skull. Sternocleidomastoid muscle The sternocleidomastoid muscle is one of the largest and most superficial cervical muscles. The primary actions of the muscle are rotation of the head to the opposite side and flexion of the neck. The sternocleidomastoid is innervated by the accessory nerve. It is given