The brachialis is a muscle in the anterior compartment of the upper arm. It lies deep to the biceps brachii and forms the floor of the cubital fossa. Attachments: Originates from the medial and lateral surfaces of the humerus shaft. It inserts onto the ulnar tuberosity, immediately distal to the elbow joint. Function: Flexion at the elbow. Innervation: Musculocutaneous nerve (with contributions from the radial nerve). Blood supply: Brachial artery and radial artery By TeachMeSeries Ltd (2025) Fig 1The coracobrachialis, biceps brachii and brachialis muscles of the anterior upper arm. Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Print Article Rate This Article