A superficial postvertebral muscle innervated by the posterior ramus of the cervical spinal nerve with origins in the upper thoracic and lower cervical spinous processes whose actions are to extend and ipsilaterally rotate the head and neck. Examples: splenius capitis, splenius cervicis [ http://en.wikipedia.org/wiki/Splenius http://orcid.org/0000-0002-6601-2165 ]