The supraspinous fossa (supraspinatus fossa, supraspinatous fossa) of the posterior aspect of the

scapula The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on eith ...

(the shoulder blade) is smaller than the infraspinous fossa, concave, smooth, and broader at its vertebral than at its humeral end. Its medial two-thirds give origin to the Supraspinatus.

Structure

The fossa can be exposed by the removal of skin and the

superficial fascia A fascia (; plural fasciae or fascias; adjective fascial; from Latin: "band") is a band or sheet of connective tissue, primarily collagen, beneath the skin that attaches to, stabilizes, encloses, and separates muscles and other internal organ ...

of the back and the trapezius muscle. The supraspinous fossa is bounded by the

spine of scapula The spine of the scapula or scapular spine is a prominent plate of bone, which crosses obliquely the medial four-fifths of the scapula at its upper part, and separates the supra- from the infraspinatous fossa. Structure It begins at the vertica ...

on the inferior side, acromion process on the lateral side and the

superior angle of scapula The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on eithe ...

on the superior side. Supraspinatus muscle originates from the supraspinous fossa. Distal attachment of the

levator scapulae muscle The levator scapulae is a slender skeletal muscle situated at the back and side of the neck. As the Latin name suggests, its main function is to lift the scapula. Anatomy Attachments The muscle descends diagonally from its origin to its inserti ...

is also on the medial aspect of the fossa.

Function

The suprascapular artery and

nerve A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the ...

are found within the fossa. The posterior branch of the suprascapular artery supplies the supraspinatous muscle. Dorsal scapular artery also gives off a collateral branch and

anastomoses An anastomosis (, plural anastomoses) is a connection or opening between two things (especially cavities or passages) that are normally diverging or branching, such as between blood vessels, leaf veins, or streams. Such a connection may be norm ...

with the suprascapular artery. Suprascapular nerve from the

brachial plexus The brachial plexus is a network () of nerves formed by the anterior rami of the lower four cervical nerves and first thoracic nerve ( C5, C6, C7, C8, and T1). This plexus extends from the spinal cord, through the cervicoaxillary canal in t ...

passes through the suprascapular notch as it approaches the fossa to supply the supraspinatus muscle. Suprascapular artery and nerve descend together but are separated by the superior transverse scapular ligament at the suprascapular notch.

Clinical significance

Rotator cuff tear

Hollowing in the supraspinous and the infraspinous area is frequently seen as chronic rotator cuff tear resulting in wasting. The wasting may be caused by the supraglenoid cyst compressing the suprascapular nerve and causes a loss of innervation to supraspinatus and infraspinatus muscles. Such wasting or hollowing can be differentially diagnosed as nerve compression or tendon rupture.

Additional images

File:Posterior surface of scapula.jpg, The human scapula File:Supraspinous fossa of left scapula - animation01.gif, Supraspinous fossa shown in red. File:Supraspinous fossa of scapula - animation02.gif, Supraspinous fossa shown in red.

References

External links

* {{Authority control Scapula