obliquus capitis superior muscle obliquus capitis superior muscle the obliquus capitis superior muscle (/əˈblaɪkwəs ˈkæpɪtɪs/) is a small muscle in the upper back part of the neck and is one of the suboccipital muscles and part of the suboccipital triangle. it arises from the lateral mass of the atlas bone. it passes superiorly and posteriorly to insert into the lateral half of the inferior nuchal line on the external surface of the occipital bone. the muscle is innervated by the suboccipital nerve, the dorsal ramus of the first spinal nerve. obliquus capitis superior muscleskull seen from behind (obliquus capitis superior shown in red)obliquus capitis superior (red) and its relationship to other suboccipital muscles.detailsoriginlateral mass of atlasinsertionlateral half of the inferior nuchal linenervesuboccipital nerveactionsextends head and flex head to the ipsilateral sideidentifierslatinmusculus obliquus capitis superiorta98a04.2.02.006ta22251fma32527anatomical terms of muscle it acts at the atlanto-occipital joint to extend the head and flex the head to the ipsilateral side. additional images position of obliquus capitis superior (shown in red). animation. still image. posterior view. deep muscles of the back (obliquus capitis superior labeled at upper left) occipital bone. outer surface. muscle attachments are shown as red circles. base of skull. inferior surface. muscle attachments are shown as red circles.