HumerusThe humerus (; pl.: humeri) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeralupper extremity consists of a rounded head, a narrow neck, and two short processes (tubercles, sometimes called tuberosities). The shaft is cylindrical in its upper portion, and more prismatic below.
Greater tubercleThe greater tubercle of the humerus is the outward part the upper end of that bone, adjacent to the large rounded prominence of the humerus head. It provides attachment points for the supraspinatus, infraspinatus, and teres minor muscles, three of the four muscles of the rotator cuff, a muscle group that stabilizes the shoulder joint. In doing so the tubercle acts as a location for the transfer of forces from the rotator cuff muscles to the humerus.
Bicipital grooveThe bicipital groove (intertubercular groove, sulcus intertubercularis) is a deep groove on the humerus that separates the greater tubercle from the lesser tubercle. It allows for the long tendon of the biceps brachii muscle to pass. StructureThe bicipital groove separates the greater tubercle from the lesser tubercle. It is usually around 8 cm long and 1 cm wide in adults.
Anatomical neck of humerusThe anatomical neck of the humerus is obliquely directed, forming an obtuse angle with the body of thehumerus. It represents the fused epiphyseal plate. StructureThe anatomical neck divides the head of the humerus from the greater and lesser tubercles of the humerus. It gives attachment to the capsular ligament of the shoulder joint except at the upper inferior-medial aspects.
Subscapularis muscleThe subscapularis is a large triangular muscle which fills the subscapular fossa and inserts into the lesser tubercle of the humerus and the front of the capsule of the shoulder-joint.*As an Amazon Associate I earn from qualifying purchases.