Surface Features of the Axial Skeleton

passageways for the supraorbital nerve, artery and vein

location of the eyebrows

one of four pairs of paranasal air sinuses. The paranasal air sinuses lighten our skulls, humidify and heat the air we inhale, they increase the resonance of speech, and are thought to serve as “crumple zones” to protect the brain, nerves and vessels in the event of facial trauma.

the serrated suture between the frontal bone and the left and right parietal bones

the serrated suture between the right and left parietal bones.

the squamosal suture between each parietal bone and the associated temporal bones.

the suture between the two parietal bones and the occipital bones

insertion of the sternocleidomastoid muscle. The inside of the mastoid process contains the mastoid air cells. These hollow areas are thought to serve as “crumple zones” to protect the delicate structures of the ear.

-structural component of the temporal bone. The temporal lobe of the brain rest next to the internal aspect of this bone.

-the structure that articulates with the temporal process of the zygomatic bone. The two processes together form the zygomatic arch.

the opening into the ear. Sound, which is moving air, enters this opening and makes contact with the tympanic membrane.

-the site of articulation with the mandibular condyles. This articulation forms the temporomandibular joint (TMJ). This joint is of particular clinical significance in that it is a malalignment of this joint that is responsible for TMJ Syndrome.

passageway for the internal jugular vein, Glossopharyngeal nerve (CN IX), Vagus nerve (CN X), and Spinal Accessory nerve (CN XI). Listed here as well as with the temporal bone because this irregular shaped foramen is in the suture between the occipital bone and temporal bones, the occipitotemporal suture

-passageway for the internal carotid artery

point of exit of the Vestibulocochlear (Auditory) nerve (CN VIII) and the Facial nerve (CN VII) from the petrous portion of the temporal bone.

-point of attachment of the stylohyoid ligaments which anchor the hyoid bone.

houses the structures of the middle and inner ear

the squamosal suture between each parietal bone and the associated temporal bones.

articulate with the superior articular surfaces (facets) of the atlas (C1) to form the atlantooccipital joint.

the large hole, largest foramen in the skull, through which the spinal cord exits the cranial vault

passageway for the internal jugular vein, Glossopharyngeal nerve (CN IX), Vagus nerve (CN X), and Spinal Accessory nerve (CN XI). Listed here as well as with the temporal bone because this irregular shaped foramen is in the suture between the occipital bone and temporal bones, the occipitotemporal suture.

the suture between the two parietal bones and the occipital bones.

-these are irregular bones that sometimes form in the lambdoid suture, an example of variation in people.

attachment surface on its inferomedial side for the semispinalis capitis muscle, and on its inferolateral side for the obliquus capitis superior.

the body of the sphenoid bone is hollow and contains the sphenoid sinus

contributes to the floor of the cranial vault and forms the dorsal walls of the orbital fossae. Forms the superior orbital fissure along with the lesser wings

contributes to the floor of the anterior aspect of the floor of the cranial vault. Along with the greater wings, forms the superior orbital fissure

superior aspect of the body of the sphenoid bone, location of the pituitary gland

passageway for the Optic nerve (CN II) and the ophthalmic artery.f. Superior orbital fissure-slit-like opening between the greater and lesser wings. Passageway for the Oculomotor nerve (CN III), Trochlear nerve (CN IV), Ophthalmic branch of the Trigeminal nerve or simply the Ophthalmic nerve (CN V), Abducens nerve (CN VI) and the ophthalmic vein.

passageway for the Maxillary branch of the Trigeminal nerve or simply the Maxillary nerve (CN V)

passageway for the Mandibular branch of the Trigeminal nerve orsimply the Mandibular nerve (CN V)

passageway for the pharyngeal artery, auditory tube and internal carotid artery.

passageway for the middle meningeal vessels

points of attachment for the pterygoid muscles.

the hollow area within the body of the sphenoid bone.

superior aspect of the ethmoid bone contains small foramen called the cribriform foramen. The olfactory bulbs sit here.

passageways for the Olfactory nerves (CN I)

anchors the dura mater of the meninges

hollow area within the ethmoid bone

forms the superior aspect of the nasal septum, articulates with the vomer bone which forms the inferior aspect of the nasal septum

forms medial aspect of the orbital fossa

form the bridge of nose

Lacrimal foramen-passageway for the nasolacrimal duct (tear duct)

Inferior aspect articulates with the palatine processes of the Maxilla (anterior) andthe horizontal plates of the Palatine bones (posterior). Superior aspect articulates with the perpendicular plate of the ethmoid bone (anterior) and the inferior aspect of the body of the sphenoid bone (posterior).

Create turbulence in the air we inhale, helps remove particulate matter from the air before we inhale it into our respiratory passageways.

fuses with the zygomatic process of the temporal bone to formthe zygomatic arch

articulates with the maxilla

articulates with the frontal bone

one of the four paranasal air sinuseshe paranasal air sinuses lighten our skulls, humidify and heat the air we inhale, they increase the resonance of speech, and are thought to serve “crumple zones” to protect the brain, nerves and vessels in the event of facial trauma.

passageway for the nasopalatine nerve

articulates with the horizontal plates of the palatine bones to form the hard palate of the roof of the mouth

articulates with the frontal bone.

contains the alveolar processes and the alveoli

the sockets the teeth are in. Each tooth is anchored in its alveolus by a periodontal ligament. These joints are gomphoses.

the small bony projections between the alveoli, provide structural support.

posterior inferior aspect of the ramus of the mandible. One of the points ofattachment for the masseter an medial pterygoid muscles

point of attachment for the temporalis, masseter, medial pterygoid and lateral pterygoid muscles.

articulate with the mandibular fossa. This articulation formsthe temporomandibular joint (TMJ).

holes in the body which are passageways for the inferior alveolarnerves and the mental arteries.

runs from one ramus to the other ramus, the anterior most aspect of the mandible. Contains the mental foramen and the alveoli.

-point of attachment of the temporalis muscle.

contains the alveolar processes and the alveoli

the sockets the teeth are in. Each tooth is anchored in its alveolus by a periodontal ligament. These joints are gomphoses.

The hyoid bone attaches via the stylohyoid ligaments to the styloid processes of the temporal bone. The supra & infrahyoid muscles pull the hyoid bone dorsally when a person swallows; this aids in swallowing

major structural component of the vertebrae, an intervertebral disc sits between every two vertebral bodies. This fibrocartilage discs between vertebrae create a segmented vertebral column (subphylum vertebrata) and allows for flexion and extension of the spine.

anterior aspect of the vertebral arch, the point of attachment of the vertebral arch to the vertebral body.

posterior aspect of the vertebral arch, the laminae fuse to form the spinous process.

opening within the vertebra arch, passageway for the spinal cord.

space between every two vertebrae, passageways for the spinal nerves.

important attachment sites for muscles

formed from the fusion of the laminae. Important attachment sites for muscles

articulate with the underlying inferior articulating processes to form intervertebral joints

articulate with the overlying superior articulating processes to form intervertebral joints

Bifurcated spinous processes and transverse foramen in the transverse processes. These are the passageways for the vertebral arteries and veins

Superior articular surfaces (facets)-articular surfaces for the occipital condyles of the occipital bone, form the atlantooccipital joint.

b. Inferior facets-articulate with the superior facets of the Axis (C2)

c. Fovea dentis-articulates with the dens of the Axis to form the atlantoaxial joint

Dens or odontoid process-articulates with the fovea dentis of the Atlas to form the atlantoaxial joint.

Facets on the transverse processes for articulation with the tubercles of ribs, and facets (T10 – T12) and demi facets (T1 – T9) on the bodies for articulation with the heads of the ribs. These are costovertebral joints

Large, massive vertebral bodies and square spinous processes.

Consist of five fused sacral vertebrae.

Consist of 3 to 5 fused coccygeal vertebrae. This variation is a function of where one’s tail breaks off before birth.

made of three fused bones, the manubrium, gladiolus (body) and xiphoid process. All are important clinical landmarks

Twelve pairs, the first seven are true, the last five are false. The last two of the last five; that is, ribs 11 and 12, are floating.

The true ribs have their own hyaline cartilage connection to the sternum (sternocostal joints), the next five share a cartilaginous connection, and the last two, the floating ribs, are not connected to the sternum.