Superior nuchal line, external occipital protuberance, nuchal ligament, spinout processes c7t12 insertion. Anatomy, head and neck, occipital bone, artery, vein, and nerve. It is trapezoidal in shape and curved on itself like a shallow dish. The bump on back of skull, for muscle attachment, runs between the superior and inferior nuchal line. This book is distributed under the terms of the creative commons.
It inserts onto the lateral third of clavicle, acromion, and spine of scapula. Lateral to either side of the protrusion is the superior nuchal line. External occipital protuberance definition of external. From the external occipital protuberance a ridge or crest, the median nuchal line, often faintly marked, descends to the foramen magnum, and affords attachment. At the midline of the bone, there is a protrusion called the external occipital protuberance, the tip of it is referred to as the inion. Diagram at this human musculoskeletal system article is a stub. The occipital and petrous temporal bones encase the cerebellum dorsally and laterally.
The occipital bone is a cranial dermal bone and the main bone of the occiput it is trapezoidal in. A projection of the occipital bone for muscle attachment. Going from superficial to deep, the scalp layers are skin, dense connective. The inion is the most prominent projection of the protuberance which is located at the posterioinferior lower rear part of the human skull. The scalp, which consists of five layers, covers the bone. Ta a prominence about the center of the outer surface of the squamous portion of the occipital bone, giving attachment to the ligamentum nuchae. The trapezius arises from the medial third of superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of c7t12 vertebrae and lumbar and sacral spinous processes. It is considered a flat bone, like all other cranial bones, meaning that its primary function is either for protection or to provide a broad surface for muscle attachment. The midline skin incision extends from the external occipital protuberance to the level of the eyes. Near the middle of the squamous part of occipital bone is the external occipital protuberance, the highest point of which is referred to as the inion. The external occipital crest is part of the external surface of the squamous part of the occipital bone. This lump in the middle is external occipital protuberance a bony bump on bone that allow attachment of soft tissue, muscles, tendons, and nerves permits 6, it point for several neck muscles. The external occipital protuberance is a prominence around the center of the parietal surface of the squama that diverges significantly in its vividness and protrusion, and functions as the connection of the ligamentum nuchae.
It is a site of attachment for a ligament of the posterior neck. The external occipital protuberance eop size was defined as the. Due to its many attachments and features, the occipital bone is described in terms of separate parts. The cerebrum is covered dorsally largely by the parietal bones, with smaller. The right and left transverse sinuses originate at the torcular herophili and course laterally from the internal occipital protuberance in a shallow groove between the attachments of the tentorium to the inner surface of the occipital bone. On its outside surface, at the posterior midline, is a small protrusion called the external occipital protuberance, which serves as an attachment site for a ligament. The right transverse and sigmoid sinus and the right jugular vein are the main effluent route to the superficial venous system, whereas the left transverse and sigmoid sinus and the left internal jugular vein drain the venous blood. Anatomy, head and neck, occipital bone, artery, vein, and. On its outside surface, at the posterior midline, is a small protrusion called the external occipital protuberance, which serves as an attachment. The large oval opening in the bone is called the foramen magnum through which. The occipital bone is the most posterior cranial bone and the main bone of the occiput.
Human anatomy lab occipital bone questions and study. The occipital bone is a trapezoidalshaped bone forming the base of the skull. At its midline is a prominence called the external occipital protuberance with. The occipital bone overlies the occipital lobes of the cerebrum. External occipital protuberance an overview sciencedirect topics.
It is a ridge along the midline, beginning at the external occipital protuberance and descending to the foramen magnum, that gives attachment to the nuchal ligament. From the external occipital protuberance, an often faintly protuberance lies on ectocranial midline where several nuchal muscles attach to and below these lines function skin. A conelike protrusion of the protuberantia occipitalis externa is, however, only found in male skulls of the test group e. Kerrie bolton, peter selvaratnam, in headache, orofacial pain and bruxism, 2009. Transverse axis through external auditory meatus lateral. Terms in this set 48 external occipital protuberance. The nuchal ligament and trapezius muscle attach to it. What muscles attach to the external occipital protuberance. The internal occipital protuberance separates these cavities dorsally and provides attachment for the tentorium cerebelli, the tentshaped extension of the dura mater that forms a partition between the cerebrum and cerebellum. At the base of skull in the occipital bone, there is a large oval opening called the foramen magnum, which allows the. The superior nuchal lines spread laterally toward the temporal bone on either side of the protuberance.