semispinal muscle of thorax


A muscle with origin from the fifth to the eleventh thoracic vertebrae, with insertion into the first four thoracic vertebrae and the fifth and seventh cervical vertebrae, with nerve supply from the dorsal branches of the cervical and the thoracic nerves, and whose action extends the vertebral column.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.