Sail sign (elbow)

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The sail sign on an elbow radiograph, also known as the anterior fat pad sign, describes the elevation of the anterior fat pad to create a silhouette similar to a billowing spinnaker sail from a boat. It indicates the presence of an elbow joint effusion.

The anterior fat pad is usually concealed within the coronoid fossa or seen parallelling the anterior humeral line. When there is a joint effusion, the anterior fat pad (which is intra-articular, but extrasynovial) becomes elevated.

Elevation of the anterior fat pad usually heralds the presence of an intra-articular fracture. In adults, this is usually a radial head fracture whereas in children, the commonest cause of a raised elbow fat pad is a supracondylar fracture.

In the context of acute trauma, where a fat pad is raised and no fracture is demonstrated, an occult fracture should be suspected.

Video tutorial

{{youtube~~:http://www.youtube.com/watch?v=k1UYfi9zdOg~~:k1UYfi9zdOg}}

sail signs
- sail sign: the raised anterior fat pad on an elbow radiograph
- thymic sail sign: normal thymus on a paediatric chest radiograph
- spinnaker-sail sign (angel wing sign): thymus outlined in pneumomediastinum
- retrocardiac sail sign: left lower lobe collapse on a chest radiograph
- laryngeal sail sign: unilateral dilated laryngeal ventricle in vocal cord paralysis
posterior fat pad sign (elbow)

-The sail sign on an <a href="/articles/elbow-radiograph-an-approach-1">elbow radiograph</a>, also known as the anterior fat pad sign, describes the elevation of the <a href="/articles/anterior-fat-pad">anterior fat pad</a> to create a silhouette similar to a billowing spinnaker sail from a boat. It indicates the presence of an <a href="/articles/elbow-joint-effusion">elbow joint effusion</a>.The anterior fat pad is usually concealed within the <a href="/articles/coronoid-fossa">coronoid fossa</a> or seen parallelling the anterior humeral line. When there is a joint effusion, the anterior fat pad (which is intra-articular, but extrasynovial) becomes elevated.Elevation of the anterior fat pad usually heralds the presence of an intra-articular fracture. In adults, this is usually a <a href="/articles/radial-head-fracture-2">radial head fracture</a> whereas in children, the commonest cause of a raised <a href="/articles/elbow-fat-pad">elbow fat pad</a> is a <a href="/articles/supracondylar-humeral-fracture-2">supracondylar fracture</a>. In the context of acute trauma, where a fat pad is raised and no fracture is demonstrated, an <a href="/articles/occult-fracture">occult fracture</a> should be suspected.<h4>Video tutorial</h4>{{youtube:http://www.youtube.com/watch?v=k1UYfi9zdOg}}<h4>See also</h4><ul>
~~-<li>~~
~~-<a href="/articles/sail-sign-disambiguation-1">sail signs</a><ul>~~
~~-<li>~~
~~-sail sign: the raised anterior fat pad on an elbow radiograph</li>~~
~~-<li>~~
~~-<a href="/articles/thymic-sail-sign">thymic sail sign</a>: normal thymus on a paediatric chest radiograph</li>~~
~~-<li>~~
~~-<a href="/articles/spinnaker-sign-mediastinum">spinnaker-sail sign</a> (angel wing sign): thymus outlined in pneumomediastinum</li>~~
~~-<li>~~
~~-<a href="/articles/retrocardiac-sail-sign">retrocardiac sail sign</a>: left lower lobe collapse on a chest radiograph</li>~~
~~-<li>~~
~~-<a href="/articles/sail-sign-larynx">laryngeal sail sign</a>: unilateral dilated laryngeal ventricle in vocal cord paralysis</li>~~
~~-</ul>~~
~~-</li>~~
~~-<li><a href="/articles/posterior-fat-pad-sign-elbow">posterior fat pad sign (elbow)</a></li>~~
+The sail sign on an <a href="/articles/elbow-radiograph-an-approach-1">elbow radiograph</a>, also known as the anterior fat pad sign, describes the elevation of the <a href="/articles/anterior-fat-pad">anterior fat pad</a> to create a silhouette similar to a billowing spinnaker sail from a boat. It indicates the presence of an <a href="/articles/elbow-joint-effusion">elbow joint effusion</a>.The anterior fat pad is usually concealed within the <a href="/articles/coronoid-fossa">coronoid fossa</a> or seen parallelling the anterior humeral line. When there is a joint effusion, the anterior fat pad (which is intra-articular, but extrasynovial) becomes elevated.Elevation of the anterior fat pad usually heralds the presence of an intra-articular fracture. In adults, this is usually a <a href="/articles/radial-head-fracture-2">radial head fracture</a> whereas in children, the commonest cause of a raised <a href="/articles/elbow-fat-pad">elbow fat pad</a> is a <a href="/articles/supracondylar-humeral-fracture-2">supracondylar fracture</a>. In the context of acute trauma, where a fat pad is raised and no fracture is demonstrated, an <a href="/articles/occult-fracture">occult fracture</a> should be suspected.<h4>Video</h4>{{youtube:k1UYfi9zdOg}}<h4>See also</h4><ul>
+<li>
+<a href="/articles/sail-sign-disambiguation-1">sail signs</a>
+<ul>
+<li>sail sign: the raised anterior fat pad on an elbow radiograph</li>
+<li><a href="/articles/thymic-sail-sign">thymic sail sign</a>: normal thymus on a paediatric chest radiograph</li>
+<li><a href="/articles/spinnaker-sign-mediastinum">spinnaker-sail sign</a> (angel wing sign): thymus outlined in pneumomediastinum</li>
+<li><a href="/articles/retrocardiac-sail-sign">retrocardiac sail sign</a>: left lower lobe collapse on a chest radiograph</li>
+<li><a href="/articles/sail-sign-larynx">laryngeal sail sign</a>: unilateral dilated laryngeal ventricle in vocal cord paralysis</li>
+</ul>
+</li>
+<li><a href="/articles/posterior-fat-pad-sign-elbow">posterior fat pad sign (elbow)</a></li>

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Sail sign (elbow)

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