Cranial Bones
Encase the brain and together form the calvaria (also known as the “skull cap”), which consists of several of the cranial bones joined at immovable joints called sutures. These bones also form the cranial base, which contains indentations that accommodate the brain, called the anterior, middle, and posterior cranial fossae.
Eight Cranial Bones
- Frontal
- Parietal Bones (2)
- Temporal Bones (2)
- Occipital
- Sphenoid
- Ethmoid
Facial Bones
The 14 facial bones form the framework for the face, provide openings for ventilation and eating, and form cavities for the sense organs.
14 Facial Bones
- Mandible
- Maxillae (2)
- Lacrimal Bones (2)*
- Nasal Bones (2)
- Vomer
- Inferior Nasal Conchae (2)*
- Palatine Bones (2)
- Zygomatic Bones (2)
General name for the skull’s immovable joints
Sutures
Paranasal Sinuses (Function)
Air from the nasal cavity enters the paranasal sinuses via small openings in the bones, and in the sinuses air gets filtered, warmed, and humidified.
Bony Orbits
The cavity containing the lateral bony projections called conchae.
The Nasal Cavity
The structure of the Temporomandibular Joint
The mandibular condyle fits into a depression in the temporal bone.
Bones that form the nasal septum
- Ethmoid bone (perpendicular plate)
- Vomer
Bones that form the hard palate
- Palatine Process of the Maxilla
- Horizontal Plate of Palatine Bone
Fetal Fontanel
Large, membrane-covered areas. (“soft spots”)
- Anterior Fontanel
- Posterior Fontanel
Anterior Fontanel
Where the sagittal and coronal sutures meet
Posterior Fontanel
Where the sagittal and lambdoid sutures meet.
Coronal Suture
Squamous Suture
Lambdoid Suture
Sagittal Suture
Zygomatic Process of the Temporal Bone
- Forms part of the cheekbone.
External Auditory Meatus of Temporal Bone
Styloid Process of Temporal Bone
Mastoid Process of Temporal Bone
Carotid Canal - for carotid artery - of Temporal Bone
Jugular Foramen - for jugular vein - Between occipital and temporal bones
Foramen Magnum of Occipital Bone
- For the spinal cord to pass through
Occipital Condyles - articulate with C1 - of Occipital Bone
Sella Turcia of Sphenoid Bone
- Normally houses the pituitary gland.
Optic Canals - for optic nerve - of Sphenoid Bone
Cribiform Plate of Ethmoid Bone
- Forms the roof of the nasal cavity
The little dots
Olfactory Foramina of Ethmoid Bone
- Through which olfactory nerves pass
Crista Galli of Ethmoid Bone
Lesser Wing of Sphenoid Bone
Greater Wing of Sphenoid Bone
Perdendicular Plate of Ethmoid Bone
- Forms the superior part of the bony nasal septum
Body of Mandibular Bone
Angle of Mandibular Bone
Ramus of Mandibular Bone
Condyle of Mandibular Bone
Alveolar Margins of Mandibular Bone and Maxillae
- Border between the teeth and bones
Zygomatic Process of Maxilla
24 Bones of the Vertebral Column
- Cervical Vertebrae (7) [C1-C7]
- Thoracic Vertebrae (12) [T1-T12]
- Lumbar Vertebrae (5) [L1-L5]
- Sacral Vertebrae (Fused) [S1-S1]
- Coccyx (Fused) [C1-C4]
Intervertebral Disk
Between each vertebral body is a fibrocartilage pad.
Transverse Formina
All cervical vertebrae have holes in their tranverse processes called transverse foramina. There foramina permit the passage of blodd vessels called the vertebral artery and vein.
Atlas (C1)
The atlas is the first cervical vertebra that articulates with the occipital bone. It is easily identified because it has a large vertebral foramen, no body, and no spinous process.
Axis (C2)
The axis is the second cervical vertebra. It is also easily identified by a superior projection called the dens (or the odontoid process). The dens fits up inside the atlas to form the atlanto-axial joint, which allows rotation of the head.
The 12 thoracic vertebrae share the following common features:
- The spinous processes are thin and point inferiorly.
- All have two costal facets that articulate with the ribs (there are 12 pairs of ribs)
- All have triangular vertebral foramina.
- If you look at a thoracic vertebra from the posterior side, it looks like a giraffe.
The 5 lumbar vertebrae share the following common features:
- All have a large, block -like body.
- The spinous processes are thick and point posteriorly
- If you look at a lumbar vertebra from the posterior side, it looks like a moose.
Fused bones in the Sacrum
5
Fused bone in the Coccyx
3 to 5
Sacral Foramina
Spinal nerves pass through these holes
The lateral surfaces of the Sacrum.
Articulate with the hip bones to form the sacroilica joints
Sacroiliac Joints
the joint between the lateral sacrum and the hip bone. (one on each side)
C1-C7
T1-T12
L1-L5
Vertebral Foramen - for passage of spinal cord
Passage of spinal cord, C1-L1/L2; Nerve roots, L3-L5
Transverse Foramina in transverse processes - for vertebral artery and vein
Body of C2-C7
Spinous Process of C2-C7
Body of C2-C7
Spinous Process of C2-C7
Superior Articular Facet of C1 - articulates with occipital condyles of skull
Dens of C2 - articulates with C1
Body T1-T12
Transverse Process of T1-T12
Spinous Process of T1-T12
Pedicles T1-T12
Laminae T1-T12
Superior Articular Process and Facet - for articulation with vertebra above T1-T12
Superior Costal Facets - for articulation with ribs
Transverse Costal Facet - for articulation with ribs
Inferior Costal Facets - for articulation with ribs - T’s only
Body L1-L5
Vertebral Foramen L1-L5
Transverse Process L1-L5
Spinous Process L1-L5
Pedicles L1-L5
Laminae L1-L5
Superior Articular Process and Facet - for articulation with vertebra above L1-L5
Inferior Articular Process and Facet - for articulation with vertebra below L1-L5
Bodies of S1-S5 on Anterior Sacral Surface
Sacral Foramina (for spinal nerves)
Coccyx
Superior Articular Facets (Sacrum)
Medial Sacral Crest
Sacral Canal (for nerve roots)
3 Parts of the Sternum
- Upper Manubrium
- Middle Body
- Lower Xiphoid Process
True Ribs
Ribs 1-7
Because they attach directly to the sternum by their own cartilage
False Ribs
Ribs 8-10
Becasue they attach to the cartilage of the true ribs rather than directly to the sternum
Floating Ribs
RIbs 11 & 12
Because they lack an attachment to the sternum
Ribs connect to the…
Thoracic Vertebra
Manubrium
Body Of Sternum
Xiphoid Process of Sternum
True Ribs (1-7)
False Ribs (8-10)
Floating Ribs (11 & 12)
Hyoid Bone
Is often classified as a skull bone, although it does not articulate with any skull bone or any other bone. It is held in place in the superior neck by muscles and ligaments, and it helps to form part of the framework for the larynx (voice box). It also serves as an attachment site for the muscles of the tongue and aids in swallowing.
Costal Cartilage
Costal Margin
Intercostal Spaces
