Original sentence: , abduction—away from the midline of the body) and away from the palm (i.As the name suggests, this muscle is an extensor at the wrist joint, and travels along the radial side of the arm, so will also abduct the hand at the wrist.Being an extensor contained in the forearm, it is innervated by the radial nerve.Extensor carpi radialis longus is one of the five main muscles that control movement at the wrist.It initially runs along with brachioradialis, but becomes mostly tendon early on, running between brachioradialis and extensor carpi radialis brevis.It originates from the lower third of the lateral supracondylar ridge of the humerus, from the  lateral intermuscular septum, and by a few fibers from the lateral epicondyle of the humerus.This muscle is quite long, starting on the lateral side of the humerus, and attaching to the base of the second metacarpal bone of the index finger
Edited sentence: , abduction—away from the mid-position of the hand) and away from the palmar side (i.As the name suggests, this muscle is an extensor at the wrist joint—an action also known as dorsiflexion—and travels along the radial side of the arm, so will also abduct (radial abduction) the hand at the wrist.Being an extensor contained in the forearm, it is innervated by the deep branch of the radial nerve (C7).Extensor carpi radialis longus is one of the five main muscles that control movements at the wrist.It originates from the lateral supracondylar ridge of the humerus, from the lateral intermuscular septum, and by a few fibers from the lateral epicondyle of the humerus.One of the three muscles of the radial forearm group, it initially runs along with brachioradialis, but becomes mostly tendon early on.Passing between brachioradialis and extensor carpi radialis brevis, this tendon continues into the second tendon compartment together with the latter muscle.This muscle is quite long, starting on the lateral side of the humerus, and attaching to the base of the second metacarpal bone (metacarpal of the index finger)