[TA] muscle of thorax; origin, tips of transverse processes of C7 and T1-T11 vertebrae; insertion, ribs, between tubercle and angle; action, elevate ribs for deep inspiration; nerve, dorsal rami of C8-T11 spinal nerves.levatores costarum longi (muscles), levatores costarum breves (muscles) SYN: elevator muscle of rib, musculus levator costae.