[Music] the triceps brachii the triceps brachii is a large muzzle and it forms most of the area on the back of the arm as the name indicates the tri meaning three and sep's meaning heads and it have three sources of origin it has a long hair a lateral head and the medial head this is the long head and it originates from the infraglenoid tubercle of the scapula so this is the infraglenoid tubercle [Music] that is the origin of the long head and the lateral head arises from the oblique ridge that is about the spiral groove on the upper part of the posterior surface of the shaft of the humerus so this is the origin of the lateral head that is the oblique ridge and finally the medial head originates from the posterior surface of the humerus that is below to the radial group so this is the radial groove and the middle head arises from the posterior part of the humerus below the radial growth and this is the little head the medial head is named because of the level of the radial groove that lies medial to the lateral head of the triceps brachii and the insertion is by the common tendon that is inserted into the posterior part of the superior surface of the olecranon process of the alna so this is the insertion that is into the posterior part of the superior surface of the olecranon process of ulna the medial head of the triceps brachii is also named as the deep head and few fibers of this deep head are inserted into the posterior aspect of the capsule of the elbow joint and they are sometimes referred to as the articularis cubity or the subankonous muscle so some fibers of this deep head or the medial head are attached to the posterior aspect of the capsule of this elbow joint and they are referred to as the articularis cubity or the sub anchorness muscle and below to the lateral head of the triceps brachii the profunda brachii artery and the radial nerve are present this is the profunda brake high and this is the radial nerve the nerve supply of this triceps brachii is by the radial nerve and each head of the triceps brachii receives a separate branch from this radial nerve so for the long head the branch from the radial nerve is the nerve to long head of triceps that arises in the axilla and for the lateral head it is the nerve to lateral head that arises in the radial groove infer the medial head the nerve to medial head of the triceps arises in the radial group in the actions the triceps brachii is a powerful extensor of the elbow joint in the long head of this triceps supports the head of the humerus during the hyperabduction of the arm [Music] and the clinical correlation that is the injury of the radial nerve in the radial group so if the radial nerve is damaged in the radial groove the extension of the elbow and the triceps reflex is lost is because of the nerve to the long head of the triceps arises from the radial nerve in the axilla so the extension of the elbow and the tricep reflex is lost so guys this is all about the triceps brachii if you like my video do subscribe to my channel and do look at some of my recent videos and playlists [Music] you