Learn more about the features of the humerus in this anatomy tutorial. Start typing and press enter to search Search …. We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. Manage consent. Close Privacy Overview This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website.
We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience. In the anatomical position, the head faces in a medial, superior, and posterior direction, where it articulates with the glenoid cavity of the scapula.
The anatomical neck of the humerus is a narrowing below the articular surface of the head. The joint capsule of the shoulder joint attaches here. The greater tubercle is the most lateral part of the proximal end of the humerus.
Three impressions mark it at the upper posterior aspect, all of which serve for the attachment of muscles. From superior to inferior, the muscles that attach at these impressions are three of the rotator cuff muscles:.
The lateral aspect of the greater tubercle is covered by the deltoid muscle , which gives the shoulder its usual rounded shape. Multiple vascular foramina also mark the lateral aspect of the greater tubercle.
The lesser tubercle is found anterior to the anatomical neck and has a smooth, palpable muscular impression. The lateral aspect of this tubercle forms the medial margin of the intertubercular sulcus. The lesser tubercle of the humerus gives attachment to the subscapularis muscle. Also, the transverse ligament of the shoulder attaches here. There is a deep groove separating the two tubercles, which is called the intertubercular sulcus. It is also known as the bicipital groove. The long tendon of the biceps brachii and a branch of the ascending circumflex humeral artery lie within the intertubercular sulcus.
A lateral lip and a medial lip form the intertubercular sulcus. The lateral lip is also known as the crest of the greater tubercle, and it gives attachment to the tendon of the pectoralis major muscle. The medial lip serves as the attachment site for the teres major muscle. Also, the tendon of the latissimus dorsi muscle attaches to its posterior aspect.
There is also a slight narrowing below the tubercles, which is known as the surgical neck of the humerus. It is a common fracture site. The axillary nerve and the posterior circumflex humeral artery lie close to the bone here. Here, the proximal extremity ends and continues as the shaft of the humerus. The shaft or body is the middle part of the humerus, and it gives attachment to several muscles.
Cross-section views reveal that the proximal half of the shaft is circular, while its distal half is triangular and flattened. The shaft of the humerus has three borders and three surfaces.
The distal end or extremity of the humerus has both articular and non-articular parts. The articular part is a modified condyle, which consists of a medial trochlea and a lateral capitulum, separated by a faint groove. This part of the humerus articulates with both ulna and radius.
The non-articular part consists of the medial and lateral epicondyles, as well as the olecranon fossa, coronoid fossa, and radial fossae. The trochlea is a projection that is shaped like a pulley and located medially, extending onto the posterior aspect of the humerus.
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