human_reference_atlas Homo sapiens rib rib 12 12 http://upload.wikimedia.org/wikipedia/commons/f/fe/Gray128.png In humans: The twelfth rib has a single articular facet on the head, which is of rather large size. It has no necks or tubercles, and is pointed at its anterior ends. The twelfth has angle nor costal groove; it is much shorter than the eleventh rib, and its head is inclined slightly downward. Sometimes the twelfth rib is even shorter than the first rib. [WP,unvetted]. MA:0001412 costa XII EMAPA:19540 uberon Wikipedia:Twelfth_rib twelfth rib UMLS:C1709948 elements are to be defined spatially/topologically rib 12 NCIT:C52767 UBERON:0004611 AS SCTID:244667008 FMA:8515 rib 12 costal region bone