Anterior, distal 1/2 of the Humerus to the coronoid process of the ulna.
The brachialis originates from the lower half of the front of the humerus, near the insertion of the deltoid muscle, which it embraces by two angular processes. Its origin extends below to within 2.5 cm of the margin of the articular surface of the humerus at the elbow joint. It also arises from the intermuscular septa of the arm, but more extensively from the medial than the lateral; it is separated from the lateral below by the brachioradialis and extensor carpi radialis longus muscles. Wiki
At the junction of the antero-inferior surface of the coronoid process with the front of the body is a rough eminence, the tuberosity of the ulna (or ulnar tuberosity), which gives insertion to a part of the Brachialis. Wiki
Flex the Elbow.
Flexion at elbow joint.
Innervation – Nerve control
The brachialis muscle is innervated by the musculocutaneous nerve, which runs on its superficial surface, between it and the biceps brachii. Part of it is also innervated by the radial nerve (proprioceptive branch) which allows it to be split during certain approaches to the arm. The divide between the two innervations is at the insertion of the deltoid. Wiki
Radial recurrent artery.
The radial recurrent artery arises from the radial artery immediately below the elbow.
It ascends between the branches of the radial nerve, lying on the supinator muscle and then between the brachioradialis muscle and the brachialis muscle, supplying these muscles and the elbow-joint, and anastomosing with the terminal part of the profunda brachii. Wiki
Triceps brachii muscle.
The Triceps brachii muscle is responsible for: Flexion of forearm, Supination of the forearm, Flexion of the arm at the shoulder. The Wellness Digest
Pictures of muscles
Trigger Point Referrals