The surgical neck of the humerus is a bony constriction at the proximal end of shaft of humerus. It is situated distal to the

greater tubercle The 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, thre ...

and

lesser tubercle The lesser tubercle of the humerus, although smaller, is more prominent than the greater tubercle: it is situated in front, and is directed medially and anteriorly. The projection of the lesser tubercle is anterior from the junction that is found ...

, and proximal to the

deltoid tuberosity In human anatomy, the deltoid tuberosity is a rough, triangular area on the anterolateral (front-side) surface of the middle of the humerus. It is a site of attachment of deltoid muscle. Structure Variation The deltoid tuberosity has been re ...

Clinical significance

The surgical neck is much more frequently fractured than the

anatomical neck of the humerus The anatomical neck of the humerus is obliquely directed, forming an obtuse angle with the body of the humerus. It represents the fused epiphyseal plate. Structure The anatomical neck divides the head of the humerus from the greater and less ...

. This type of fracture takes place when the humerus is forced in one direction while the joint capsule and the rotator cuff muscles remain intact. A fracture in this area is most likely to cause damage to the

axillary nerve The axillary nerve or the circumflex nerve is a nerve of the human body, that originates from the brachial plexus (upper trunk, posterior division, posterior cord) at the level of the axilla (armpit) and carries nerve fibers from C5 and C6. The a ...

and

posterior circumflex humeral artery The posterior humeral circumflex artery (posterior circumflex artery, posterior circumflex humeral artery) arises from the third part of axillary artery at the lower border of the subscapularis, and runs posteriorly with the axillary nerve through ...

. Damage to the axillary nerve affects function of the

teres minor The teres minor (Latin ''teres'' meaning 'rounded') is a narrow, elongated muscle of the rotator cuff. The muscle originates from the lateral border and adjacent posterior surface of the corresponding right or left scapula and inserts at both the ...

and

deltoid Deltoid (delta-shaped) can refer to: * The deltoid muscle, a muscle in the shoulder * Kite (geometry), also known as a deltoid, a type of quadrilateral * A deltoid curve, a three-cusped hypocycloid * A leaf shape * The deltoid tuberosity, a part of ...

muscles, resulting in loss of abduction of arm (from 15-90 degrees), weak flexion, extension, and rotation of shoulder as well as loss of sensation of the skin over a small part of the lateral shoulder.

Additional images

File:Neck-of-Humerus.jpg, The difference between anatomical neck and surgical neck of the humerus File:Illustrations of Dissections Plate 05 shoulder.jpg, Posterior view of the humerus showing the axillary nerve and posterior circumflex humeral artery at the surgical neck.

References

External links

* * * () Humerus {{musculoskeletal-stub

Clinical significance

Additional images

See also

References

External links