EN | DE | PT Contact How to study Login Register

Humerus - want to learn more about it?

Our engaging videos, interactive quizzes, in-depth articles and HD atlas are here to get you top results faster.

Sign up for your free Kenhub account today and join over 1,133,010 successful anatomy students.

“I would honestly say that Kenhub cut my study time in half.” – Read more. Kim Bengochea Kim Bengochea, Regis University, Denver


The humerus is the longest and largest bone of the upper limb. It consists of a proximal end, a shaft and a distal end, all which contain important anatomical landmarks. 

The humerus articulates with the scapula proximally at the glenohumeral joint so it participates in the movements of the shoulder. Also, the humerus has distal articulations with the radius and ulna at the elbow joint

The nature of the elbow joint enables the movements that are limited to the arm and forearm, and cannot be performed within the other parts of the body, such as supination and pronation.

Key Facts
Proximal End Head, anatomical neck, greater tubercle, lesser tubercle
Shaft Borders: anterior, lateral, medial
Surfaces: anterolateral, anteromedial, posterior
Distal End Articular parts: trochlea, capitulum
Non-articular parts: olecranon fossa, coronoid fossa, radial fossa
Fractures Impact, avulsion, transverse, spiral, intercondylar

This article will talk about these aspects in detail, including muscular attachments and anatomical landmarks, followed by an overview of clinical pathology related to the humerus.

Proximal End

The proximal end of the humerus consists of a head, an anatomical neck and the greater and lesser tubercles. 


The head is a hemispheroidal shape, with hyaline cartilage covering its smooth articular surface. In the anatomical position, the head faces in a medial, superior and posterior direction where it articulates with the glenoid fossa of the scapula.

Anatomical Neck

The anatomical neck is a slight narrowing below the articular surface of the head. Here, the joint capsule of the shoulder joint is attached.

Greater Tubercle

The greater tubercle is the most lateral portion of the proximal end of the humerus. It consists of three smooth and flat impressions at the posterosuperior aspect for the attachment of muscles. From superior to inferior, the muscles that attach at these impressions are the:

The deltoid muscle covers the lateral aspect of the greater tubercle, resulting in the normal rounded shape of the shoulder. The lateral aspect also contains multiple vascular foramina.

Lesser Tubercle

The lesser tubercle is located anterior to the anatomical neck and has a smooth, palpable muscular impression. The lateral part forms the medial margin of the intertubercular sulcus. The subscapularis muscle attaches at this tubercle and the transverse ligament of the shoulder also attaches on its lateral part.

Intertubercular Sulcus

The intertubercular sulcus is an indentation located between the two tubercles. It is sometimes referred to as the bicipital groove. The long tendon of the biceps brachii and a branch of the ascending circumflex humeral artery are located within the sulcus. The sulcus consists of a lateral lip and a medial lip. The tendon of the pectoralis major muscle attaches on to the lateral lip, while the teres major tendon attaches on to the medial lip. In addition, the tendon of lattisimus dorsi attaches to the posterior aspect.

Surgical Neck

There is also a narrowing below the tubercles referred to as the surgical neck, which is a common fracture site.

It is in close proximity to the axillary nerve and the posterior circumflex humeral artery. This is where the proximal end of the humerus joins with the long shaft.


Recommended video: Humerus
Anatomy, bony landmarks and function of the humerus.

The proximal half of the shaft is of a cylindrical shape, whereas the distal half is triangular. It consists of three borders known as the anterior, lateral and medial borders. The shaft also contains three surfaces referred to as the anterolateral, anteromedial and posterior surfaces.


The anterior border begins at the greater tubercle and runs downward almost to the end of the bone. The proximal end of the anterior border is continuous with the lateral lip of the intertubercular sulcus.

The lateral border begins just distal to the greater tubercle of the humerus. It thickens distally to form the lateral supracondylar ridge. The middle portion of the lateral border is adjacent to the rough V shaped area referred to as the deltoid tubercle/tuberosity.

The medial border is similar to the lateral border in that it forms the medial supracondylar ridge distally. The radial groove is a shallow groove that interrupts the medial border in its medial third. The radial nerve and deep brachial artery are located in this groove.

How well do you know the other 205 bones in the body? Test your knowledge with our bone quizzes and labeled diagrams.


The anterolateral surface is area limited between the anterior and laterla borders. It has a smooth proximal surface and is largely covered by the deltoid muscle. The deltoid inserts into the deltoid tubercle/tuberosity around the middle of the surface. The lateral portion of the brachialis muscle originates from the distal part of this surface, as well as from the proximla two third of the lateral supracondylar ridge. 

The anteromedial surface is located between the anterior and medial borders of the shaft/body, beginning proximally at the floor of the intertubercular sulcus. It provides attachment for the coracobrachialis muscle around its mid-portion, while the distal half of the surface is largely covered by the medial portion of the brachialis muscle.

The posterior surface is bounded by the medial and lateral borders and is covered mostly by the medial head of the triceps brachii muscle. A ridge on the proximal third also gives attachment to the lateral head of the triceps brachii.

Distal End

The distal end consists of both articular and non-articular parts. The articular part of the humerus is a modified condyle and is wider transversely. It articulates with both the ulna and radius and consists of a medial trochlea and a lateral capitulum, which are separated by a faint groove.

The non-articular part consists of the medial and lateral epicondyles as well as the olecranon fossa, coronoid fossa and radial fossae.


The trochlea has a surface shaped like a pulley and covers the anterior, posterior and inferior surfaces of the medial condyle of the humerus. It articulates with the ulna at the trochlear notch. When the elbow is in the extended position, the posterior and inferior aspects of the trochlea are in contact with the ulna. However, when the elbow is flexed the posterior part is no longer in contact, as the trochlear notch slides towards the anterior aspect of the humerus.


The capitulum is a convex and rounded projection that covers the anterior and inferior surfaces of the lateral condyle of the humerus. Unlike the trochlea, it doesn’t cover the posterior surface. It articulates with the head of the radius. In extension, the inferior surface is in contact with the radius but in the flexed position the radial head slides towards the anterior aspect of the humerus.

Medial Epicondyle

The medial epicondyle is a blunt projection superomedial to the medial condyle, which forms at the end of the medial border of the humerus. The ulnar nerve crosses its smooth posterior surface and is palpable in this location. The superficial muscles of the anterior compartment of the forearm originate from the anterior surface of the medial epicondyle. These muscles are the:

  • flexor carpi ulnaris
  • palmaris longus
  • flexor carpi radialis
  • pronator teres

Lateral Epicondyle

The lateral border of the humerus ends at the lateral epicondyle. There is an impression on the lateral and anterior surfaces where the seven muscles of the superficial group of the posterior compartment of the forearm originate. These include the:

  • brachioradialis
  • extensor carpi radialis longus
  • extensor carpi radialis brevis
  • extensor digitorium
  • extensor digiti minimi
  • extensor carpi ulnaris
  • anconeus

Olecranon Fossa

The olecranon fossa is a deep hollowed area on the posterior surface, superior to the trochlea. In elbow extension, the tip of the ulnar olecranon process lodges into this fossa.

Coronoid Fossa

The coronoid fossa is a smaller hollow that is also located superior to the trochlea, but on the anterior surface. During flexion of the elbow, the coronoid process of the ulna lodges into the coronoid fossa. Lateral to the coronoid fossa and superior to the capitulum is another depression referred to as the radial fossa. It is so named as the margin of the head of the radius lodges there in full flexion.



Fractures of the humerus are relatively common and can occur at any location on the humerus. At the proximal end, most fractures are located at the surgical neck and are most common in the elderly, especially those with osteoporosis.

Impact Fracture

An impact fracture, often the result of a humeral fracture, is where one bone fragment is driven into the spongy bone of another bone fragment. This is usually due to the force of a fall on the hand.

Avulsion Fracture

When the greater tubercle is pulled away from the head of the humerus the result in an avulsion fracture. It is most commonly seen in the middle-aged and in the elderly. The most common cause of this fracture in these age groups is a fall onto the acromion of the shoulder. In young adults, it can result from falling on the hand when the arm is in abduction.

Transverse Fracture

A direct blow to the arm can result in a transverse fracture of the humeral shaft. The pull of the deltoid muscle causes the proximal fragment to displace laterally.

Spiral Fracture

A fall onto the outstretched hand can also cause a spiral fracture of the shaft of the humerus. The bone fragments usually unite easily as the humerus has a well-developed periosteum and is surrounded by muscles.

Intercondylar Fracture

An intercondylar fracture can occur due to a fall on the elbow whilst it is in flexion. This results in separation of one or both of the condyles from the shaft of the humerus.

Endangered Structures

The following nerves are located on the following aspects of the humerus:

  • The axillary nerve: surgical neck
  • The radial nerve: radial groove
  • The median nerve: distal humerus
  • The ulnar nerve: medial epicondyle

If any of these aspects of the humerus are fractured, there may be damage to these nerves.

Humerus - want to learn more about it?

Our engaging videos, interactive quizzes, in-depth articles and HD atlas are here to get you top results faster.

Sign up for your free Kenhub account today and join over 1,133,010 successful anatomy students.

“I would honestly say that Kenhub cut my study time in half.” – Read more. Kim Bengochea Kim Bengochea, Regis University, Denver

Show references


  • K.L. Moore, A.F. Dalley, A.M.R. Agur: Clinically Oriented Anatomy, 5th Edition, Lippincott Williams & Wilkins (2006), p.732-3.
  • S. Standring: Gray’s Anatomy The Anatomical Basis Of Clinical Practice, 40th Edition, Elsevier Health Sciences UK (2008), p.1446-50.
  • R.L. Drake, A. Wayne, A.W.M. Mitchell: Gray’s Anatomy For Students, 2nd Edition, Churchill Livingstone (2010), p.997-1000, 1035-6, 1053-4.

Author, Review and Layout:

  • Charlotte O'Leary
  • Dimitrios Mytilinaios MD, PhD
  • Catarina Chaves


  • First Illustration Gallery - Irina Munstermann, Yousun Koh
  • Second Illustration Gallery - Yousun Koh
  • Surgical neck of the humerus - ventral view - Yousun Koh
  • Body of the humerus - ventral view - Yousun Koh
  • Third Illustration Gallery - Yousun Koh
  • Fourth Illustration Gallery - Yousun Koh
  • Coronoid fossa - ventral view - Yousun Koh
© Unless stated otherwise, all content, including illustrations are exclusive property of Kenhub GmbH, and are protected by German and international copyright laws. All rights reserved.

Related diagrams and images

Continue your learning

Read more articles

Show 9 more articles

Watch videos

Take a quiz

Browse atlas

Well done!

Register now and grab your free ultimate anatomy study guide!