What is an external occipital protuberance?
External Occipital Protuberance (EOP) is a normal anatomical structure located on the posterior surface of the occipital bone, at the level of the superior nuchal line. It is the insertion site of the nuchal ligament1.
How do you find the external occipital protuberance?
Inferior view The external occipital protuberance is a raised area on the midline of the occipital bone where the posterior wall meets the base of the skull. It is medial to the two superior nuchal lines. It is at the superior extent of the ligamentum nuchae that connects the cervical vertebrae to the skull.
What muscles attach to external occipital protuberance?
The inion is the most prominent projection of the protuberance which is located at the posterioinferior (rear lower) part of the human skull. The nuchal ligament and trapezius muscle attach to it.
What does external occipital protuberance feel like?
This may be the reason why some people — especially the younger crowd — are developing a weird, bony spike just above their necks. The bony skull bump — known as an external occipital protuberance — is sometimes so large, you can feel it by pressing your fingers on the base of your skull.
What is the function of the external occipital protuberance?
The most prominent feature of the occipital squama is the external occipital protuberance (EOP). This mound, whose summit is known as the inion, serves as the attachment site for the medial insertion of the trapezius muscle.
Is external occipital protuberance common?
External occipital protuberance is normal anatomical entity, rarely it may show hyperostosis and may get prominent and causing pain and examination reveals presence of tender bony swelling. However, such occurrence is extremely uncommon.
Why do I have external occipital protuberance?
The external occipital protuberance represents a normal anatomical prominence. Superior nuchal lines run laterally on both sides from external occipital protuberance and provides origin of trapezius muscle in its medial part. Our patient might be getting pain due to the impingement of trapezius muscle.
What is the purpose of occipital protuberance?
This opening allows for passage of the spinal cord. The occipital bone is the only cranial bone to connect to the cervical spine.
What is the main function of occipital bone?
The occipital bone is the most posterior cranial bone and the main bone of the occiput. 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.
What is the occipital process?
The occipital process (Processus occipitalis) covers the lateral surface of the petromastoid portion. It is the extension of the zygomatic temporal crest, that arrives in most species to the contact of the occipital bone.