View source for Capitulum of the humerus

{{short description|Structure of humerus}}
{{Redirect|Capitellum|the lizard genus|Capitellum (lizard)}}
{{more footnotes|date=December 2013}}
{{Infobox bone
| Name        = Capitulum of the humerus
| Latin       = capitulum humeri
| Image       = Capitulumhumeri.PNG
| Caption     = Left [[humerus]] seen from front (capitulum visible at bottom right)
| Image2      = HumerusFront.png
| Caption2    = Left [[humerus]] seen from front (part of the [[appendicular skeleton]])
}}
In human anatomy of the arm, the '''capitulum of the humerus''' is a smooth, rounded eminence on the lateral portion of the distal articular surface of the [[humerus]]. It articulates with the cup-shaped depression on the [[head of the radius]], and is limited to the front and lower part of the bone.

In non-human tetrapods, the name capitellum is generally used, with "capitulum" limited to the anteroventral articular facet of the rib (in archosauromorphs).

==Lepidosauromorpha==

[[Lepidosaurs]] show a distinct capitellum and [[Trochlea of humerus|trochlea]] on the centre of the ventral (anterior in upright taxa) surface of the humerus at the distal end.

==Archosauromorpha==

In non-avian [[archosaurs]], including crocodiles, the capitellum and the trochlea are no longer bordered by distinct etc.- and entepicondyles respectively, and the distal humerus consists two gently expanded condyles, one lateral and one medial, separated by a shallow groove and a supinator process. Romer (1976) homologizes the capitellum in Archosauromorphs with the groove separating the medial and lateral condyles.

In [[bird]]s, where forelimb anatomy has an [[adaptation (biology)|adaptation]] for flight, its functional if not<ref>{{Cite web|url=https://www2.gwu.edu/~darwin/BiSc151/Birds/Birds.HTML|title=Evolution of Birds|website=The George Washington University}}</ref> [[ontogenetic]] equivalent is the '''dorsal condyle of the humerus'''.

==Additional images==
<gallery>
File:Elbow joint - deep dissection (anterior view, human cadaver).jpg|Elbow joint. Deep dissection. Anterior view.
File:Slide1bgbg.JPG|Elbow joint. Deep dissection. Posterior view.
File:Slide3bgbg.JPG|Elbow joint. Deep dissection. Posterior view.
</gallery>

==References==
<references />
{{Gray's}}
* Romer, A.S. 1976 Osteology of the reptiles. University of Chicago Press, Chicago.

==External links==
* {{SUNYAnatomyFigs|07|02|05}}
* <!-- dead link {{BiowebUW|APLab/Table_of_Contents/Lab_04/Humerus_1/Humerus_1c/humerus_1c.html|aplab}} --> [https://web.archive.org/web/20090205191625/http://bioweb.uwlax.edu/aplab/Table_of_Contents/Lab_04/Humerus_1/Humerus_1c/humerus_1c.html BiowebUW, cached at archive.org]

{{Bones of upper extremity}}
{{Portal bar|Anatomy}}
{{Authority control}}

[[Category:Humerus]]