Homo sapiens longissimus muscle longissimus thoracis muscle http://upload.wikimedia.org/wikipedia/commons/1/1f/Longissimus.png Wikipedia:Longissimus#Longissimus_thoracis NCIT:C53169 SCTID:244859003 longissimus dorsi EMAPA:37653 musculus longissimus thoracis The longissimus thoracis is the intermediate and largest of the continuations of the sacrospinalis.[WP]. intermediate erector spinae muscle of back; origin, with iliocostalis and from transverse processes of lower thoracic vertebrae; insertion, by lateral slips into most or all of the ribs between angles and tubercles and into tips of transverse processes of upper lumbar vertebrae, and by medial slips into accessory processes of upper lumbar and transverse processes of thoracic vertebrae; action, extends vertebral column; nerve supply, dorsal primary rami of thoracic and lumbar spinal nerves[Stedmans]. FMA:22709 longissimus thoracis UMLS:C0224307 MA:0002339 BTO:0001651 longissimus dorsi muscle AAO:0010775 musculus longissimus dorsi Epaxial muscle which originates on the antero-lateral urostyle and inserts variably along the neural spines and transverse processes of the presacral vertebrae to the exoccipital bone.[AAO] TODO - add logical definition to determine if AAO class belongs here. Classified as erector spinae in AAO UBERON:0001401