The spinalis thoracis is the thoracic part of the spinalis muscle that attaches to thoracic vertebral spinous processes and continues forward as spinalis cervicis.
Origin: Extending across the spinous processes of one or more thoracic vertebrae, and sometimes last cervical vertebra
Insertion: extends forward as spinalis cervicis
Action: Extends the neck; in unilateral action to raise the neck obliquely and turn it to one side.
Nerve: Dorsal branches of the lumbar and thoracic nerves