The humerus is a long bone which consists of a shaft (diaphysis) and two extremities (epiphysis). It is the longest bone of the upper extremity.
Upper Extremity Features
The head of the humerus is the articular surface of the upper extremity, which is an irregular hemisphere.
The anatomical neck is the part between the head and the tuberosities.
The surgical neck is the part between the tuberosities and the shaft.
The greater tuberosity it is located lateral to the head.
The lesser tuberosity is located inferior to the head, on the anterior part of the humerus, Its very prominent and palpable.
Bicipital (intertubercular) groove is located between the two tuberosities. The Biceps tendon is placed here.
The body of the humerus has three borders and three surfaces.
The humerus serves as an attachment to 13 muscles which contribute to the movements of the hand and elbow, and therefore the function of the upper limb.
|Teres Minor||Greater Tubercle
Upper Part of the Lateral Border
|Pectoralis Major||Upper Part of the Anterior Border|
|Triceps Brachii||Lower Part of the Lateral Border
Lateral Supracondylar Ridge
|Brachioradialis||Lateral Supracondylar Ridge|
|Extensor Carpi Radialis Longus||Lateral Supracondylar Ridge|
|Teres Major||Crest of the Lesser Tubercle|
|Coracobrachialis||Crest of the Lesser Tubercle|
|Brachialis||Medial Supracondylar Ridge|
|Pronator Teres||Medial Supracondylar Ridge|
|Latissimus Dorsi||Bicipital Groove|
Proximal end or Head-Surgical Neck Fracture
- It is caused by a direct blow on the area or fall on an outstretched hand.
- It results in damage to the Axillary nerve and Posterior circumflex artery.
- Axillary nerve damage results in paralysis of deltoid and teres minor muscles.
- This fracture causes damage to radial nerve and Profunda brachii artery.
- Sensory loss can be seen over the dorsal surface of the hand, proximal parts of lateral 3 and a half fingers dorsally.
- Radial nerve palsy results in wrist drop.
Distal end-Supracondylar fracture
- It is a fracture of the distal humerus just above the Elbow joint.
- Humerus Varus can be caused due to haematologic, infectious, genetic and neurological disorders.
- Charcot arthropathy is a rare disorder characterised by debilitating joint destruction.
- Gray H. Anatomy of the human body [Internet]. 20th ed. Lewis WH, editor. Philadelphia: Lea & Febiger; 1918. Accessed 26 March 2020.
- Jones O. The Humerus (Updated 16 June 2019). Teach Me Anatomy. Accessed 24 March 2020
- Mostafa E, Varacallo M. Anatomy, Shoulder and Upper Limb, Humerus. InStatPearls [Internet] 2018 Dec 3. Accessed 26 March 2020