General Anatomy (Session 3) Nursing PDF

Skeleton System (Bone) Session 3 By: Dr. Shahnaz Sabetkam Assistant Professor of Anatomical Sciences Kyrenia University  Divisions of the Skeleton Axial skeleton Skull Hyoid bone Vertebral column Thoracic (rib) cage App...

Skeleton System (Bone) Session 3 By: Dr. Shahnaz Sabetkam Assistant Professor of Anatomical Sciences Kyrenia University  Divisions of the Skeleton Axial skeleton Skull Hyoid bone Vertebral column Thoracic (rib) cage Appendicular skeleton Limbs Girdles the Axial Skeleton  The Skull The skull, the body’s most complex bony structure. Functions – Protects brain – Supports organs of special senses – Provides foundation for structures that take air, food, and water into body  Different view of Cranium Norma facialis Norma lateralis Norma occipitalis Norma verticalis Norma basilaris  The adult skull Skull is made up of several cavities: 1. Cranial cavity 2. Nasal cavity 3. The orbits 4. Paranasal sinuses 5. The ears 7-7  Cranium Calvaria = Skull cap Basis cranii  Bones of the Skull 22 bones plus si6 auditory ossicles that function in hearing. Of the 22, two portions: 1- Neurocranium (brainbox) Surrounds and protects brain Provides muscle attachment Contain sinuses reduce weight of skull 2- Viscerocranium (facialbones) Gives shape to face Protect major sensory organs- eyes, nose, and tongue Provide attachment sites for muscles of mastication, facial expression, and eye movement 7-9  Viscerocranium Neurocranium Inferior nasal concha (2) Frontal (1) Lacrimal (2) Parietal (2) Vomer (1) Occipital (1) Nasal (2) Temporal (2) Zygomatic (2) Ethmoid (1) Palatin (2) Sphenoid (1) Maxilla (2) Mandibula (1)  Neurocranium Bones (Cranium ) Eight cranial bones: Two parietal, two temporal, frontal, occipital, sphenoid, and ethmoid Cranial bones are thin and remarkably strong for their weight. Neurocranium Bones (Cranium ) Frontal bone Parietal bone Occipital bone Ethmoidal bone Temporal bone Sphenoidal boone Neurocranium Bones (Cranium ) Frontal (1) – forehead & upper eye orbits Parietal (2) – sides & roof of cranium Temporal (2) – sides & floor of cranium  Neurocranium Bones (Cranium ) Sphenoid (1) base & sides of cranium, parts of orbits Ethmoid (1) – walls of nasal cavities, floor of cranium,orbits Occipital (1) – back & base of cranium Frontal Bone  Frontal Bone Forms the anterior portion of the cranium(forehead). Articulates posteriorly with the parietal bones via the coronal suture. Major markings include the supraorbital margins, the anterior cranial fossa, and the frontal sinuses (internal and lateral to the glabella).  Frontal Bone The frontal bone develops in two halves that grow together. Generally, they are completely fused by age 5 or 6. In some adults a metopic suture, a persistent frontal suture(metopic suture), is visible in the midline of the glabella, the smooth, slightly depressed area between the superciliary arches the glabella is superiorly to the nasion  Frontal The unpaired frontal bone has four parts: the unpaired squamous part the paired orbital parts and the unpaired nasal part The supra-orbital margin of the frontal bone has a supra- orbital foramen or notch for passage of the supra-orbital nerve and vessels The frontal bone also contains frontal sinuses, which are connected to the nasal cavity and are opened into middle nasal meatus (between middle and inferior conchae)  The frontal bone Squamous Part: The squamous part Parietal border The part of the frontal bone that underlies the forehead. Frontal (metopic) suture Supraorbital margin Supraorbital margin: Edge of the frontal part that forms the superior border The orbital part of the orbits. Nasal border The nasal part Anterior  Frontal bone Squamous Part: Supraorbital foramen or notch: Opening or notch in the middle of the supraorbital margin. Superciliary arches: Thickened ridges over the supraorbital margins that supports the eyebrows. Sius frontalis  The Frontal bone Frontal Eminence Glabella Superciliary arch More pronounced in men Frontal sinus  Frontal bone Supraorbital notch Supraorbital Foramen Temporal line Temporal surfaces Zygomatic process Nasal spine Anterior view  Frontal bone Foramen supraorbitale V.A.N. supraorbitalis  Frontal bone Orbital Part: The part that forms the roof of the orbit. Lacrimal fossa: Depression on the inferior surface of the orbital part that accommodates the lacrimal gland. Frontal bone Fossa for lacrimal gland Ethmoidal notch Inferior view Frontal Bone Parietal border Supraorbital margin Sphenoidal border Nasal border  Frontal Major markings include: Supraorbital margins Supraorbital notch Superciliary arches Glabella Frontal sinuses Zygomatic process Temporal line 7-34  Two frontal sinuses are separeted by a septum:  Vary in size  Absent at birth  Show by the second year and fairly well developed by seven years  Fully developed after puberty  Open into the middle meatus OCCIPITAL BONE  The Occipital Bone The occipital bone contributes to the posterior, lateral and inferior surfaces of the cranium.  OCCIPITAL BONE  Encircle the oval foramen magnum by 4 parts: 1- Basilar part: Anterior of foramen magnum 2&3-Lateral parts: Lateral of foramen magnum 4-Squamous part: Posterior of foramen magnum  The Occipital Bone Foramen magnum: Large circular opening that connects the cranial and spinal cavities. Squamous part Lateral part Basilar part  Basilar part Clivus (superior surface): slightly concave and sloped upwards in continuity with the sphenoid Pharyngeal tubercle (inferior surface) (rectus capitis anterior muscle and pharyngeal raphe are attached) Lateral part: Inferior surface: ▪ Occipital condyles ▪ Hypoglossal canal (hypoglossal nerve CN XII)  Squamous part  External occipital protuberance (INION) – a landmark easily felt  Superior nuchal line curves lateraly from this landmark  Occipital Major landmark include : Foramen magnum External occipital protuberance Superior nuchal line Occipital condyle Hypoglossal canal  The Occipital Bone External occipital protuberance Superior nuchal (Occipital) line Occipital condyle Articulate with the first cervical vertebra (Atlas) Hypoglossal duct  The Occipital Bone Pharyngeal Tubercule Clivus Occipital condyle Superior nuchal line External occipital protuberance  Parietal bone These bones contribute to the superior and lateral surface of the cranium.  Parietal Bones The skull bones, with a few exceptions, are connected by immovable joints called sutures. Some of the major sutures are: Lambdoid suture: Between the occipital and parietal bones. Sagittal suture: Between the parietal bones. Coronal suture: Between the frontal and parietal bones. Squamous suture: Between the parietal and temporal bones.  The Parietal Bone Sagittal margin Frontal border Sagittal suture Frontal bone  The Temporal Bone The temporal bones contribute to the lateral and inferior walls of the cranium. Temporal Bones 7-64  Temporal Bones Form the inferolateral aspects of the skull and parts of the cranial floor The temporal bone can be divided into 4 parts: 1. Squamous 2. Tympanic 3. Mastoid 4. Petrous Petros part  1. Squamous The squamous part is the flatened plate of bone at the sides of the skull. Projecting forward is a zygomatic process. This process with the temporal process of the zygomatic bone forms the zygomatic arch (cheekbone).. On the inferior surface is mandibular fossa, which forms a joint with the condyle of the mandible. This articulationon is the temporomandibular joint (TMJ). 7-70  The Temporal Bone Mandibular fossa Temporamandibular joint 2. Tympanic The tympanic part of the temporal bone contains the external acoustic meatus, or ear canal, which is posterior to the mandibular fossa. This part is the region that surrounds the external acoustic meatus or external auditory canal. A thin, pointed styloid process projects inferiorly from the tympanic part. This passageway ends as a tympanic membrane. 7-74 Temporal bone zygomatic process Mandibular fossa External acoustic meatus External acoustic opening 3. Mastoid The mastoid process, a rounded projection posterior to the external acoustic meatus, accounts for the mass of the mastoid part. The mastoid foramen is directly posterior to the mastoid process. The stylomastoid foramen, located between the mastoid and styloid processes, provides the passage for part of the facial nerve. The mastoid process of the temporal bone can be easily palpated as a bony knob immediately behind the earlobe. 7-77 The Temporal Bone Mastoid foramen Mastoid process 4. Petrous The petrous part can be seen in the floor of the cranium, in both anterior cranial fossa and posterior cranial fossa you can see. The structures of the middle ear and inner ear are housed in this dense part of the temporal bone. The carotid canal and the jugular foramen border on the medial side of the petrous part at the junction of the temporal and occipital bones. 7-79  Temporal bone Internal acoustic meatus Styloid process external auditory meatus  3 ossicles ⚫ malleus (handle on tympanic membrane) ⚫ incus ⚫ stapes (rest on fenestra vestibuli) Inner ear: petrous part of temporal bone ⚫ bony labyrinth Cochlea Vestibula, Semicircular canels ⚫ internal accoustic meatus: vestibulocochlear nerve (8th) and facial nerve (7th)  carotid canal for internal carotid artery internal carotid artery (ICA) Skull - 32  Temporal bone Zygomatic process Mandibular fossa Styloid process Carotid canal External acoustic opening Mastoid foramen Stylomastoid foramen Sphenoid bone  Sphenoid Bone Butterfly-shaped bone that spans the width of the middle cranial fossa Forms the central wedge that articulates with all other cranial bones. Consists of: 1. Body (median portion) 2. Two greater wings (lateral portion) 3. Two lesser wings (anterior portion) 4. Pterygoid processes (directed inferiorly)  Sphenoid Bone Body of sphenoidal bone Greater wing Lesser wing Pterygoid process Anterior  Sphenoid Bone Body of sphenoidal bone Lesser wing Greater wing Pterygoid process  Anterior view Sphenoid Bone 1- Body: The body is the central portion of the sphenoid. A prominent feature of the body is the sella turcica ("Turkish saddle") that forms a bony enclosure around the pituitary gland. Superior view 2- Greater Wings The greater wings near their attachment to the body have the following openings: Foramen rotundum: A roundopening Foramen ovale: An oval opening Foramen spinosum: passes here middle meningeal artery 3- Lesser wings: Wing-like extensions anterior to the sella turcica. opening between the lesser and body optic canal Greater Wings Large wing-like processes that extend laterally from the body. The greater wings act as a brace that strengthens the sides of the skull. Superior orbital fissure: Irregular slit-like opening between the lesser and greater wings. 4- Pterygoid processes Extending downward on either side of the body are processes called the pterygoid processes. These processes form plates (Medial and Lateral plates) that permit muscle attachment. Pterygoid canals are present at the base of these processes. 4- Pterygoid processes Extending downward on either side of the body are processes called the pterygoid processes. These processes form plates (Medial and Lateral plates) that permit muscle attachment. Pterygoid canals are present at the base of these processes. Pterygoid canal Lateral plate Medial plate Pterygoid hamulus Anterior  Sphenoid Bone Major markings: the sella turcica, hypophyseal fossa, and the pterygoid processes Major openings include : the optic canals Superior orbital fissure Foreman rotundum Foramen ovale Foramen spinosum  Sphenoid Bone Located on the inferior side of the cranium, the sphenoid bone would seem to be well protected from trauma. In fact the sphenoid is the most frequently fractured bone of the cranium. 7-113 The Ethmoidal Bone Ethmoidal Bone The Ethmoidal Bone Crista galli Ethmoidal labyrinth Perpendicular plate Anterior  The TheEthmoidal Bone Ethmoidal Bone Crista galli Superior nasal concha Cribriform plate Middle nasal concha Ethmoid air cells Ethmoidal labyrinth Perpendicular plate  Ethmoid Bone Most deep of the skull bones; lies between the sphenoid and nasal bones Forms most of the bony area between the nasal cavity and the orbits Major markings include: cribriform plate crista galli perpendicular plate Superior and middle nasal conchae ethmoid sinuses Viscerocranium Bones  Bones of the Skull Twenty-two bones plus six auditory ossicles that function in hearing. Of the twenty-two, two portions- – Neurocranium (braincase) Surrounds and protects brain provides muscle attachment Contain sinuses reduce weight of skull – Viscerocranium (facialbones) gives shape to face Protect major sensory organs- eyes, nose, and tongue Provide attachment sites for muscles of mastication, facial expression, and eye movement 7-2  Lacrimal THE FACIAL BONES Nasal 1. Lacrimal Bone 2 2. Nasal Bone 2 3. Inferior Nasal Concha 2 Inferior nasal concha Zygomatic Maxillae 4. Zygomatic Bone 2 Vomer 5. Maxilla 2 6. Palatine Bone 2 Mandible 7. Vomer 1 8. Mandible 1  The Skull Lacrimal Nasal Zygomatic Inferior Nasal Maxilla Conchae Mandible Vomer  Facial Bones – 14 bones Maxilla (2) – upper jaw, roof of mouth Nasal (2) – bridge of nose Zygomatic (2) – cheek bones, walls of orbits Lacrimal (2) – medial walls of orbits  Facial Bones Inferior nasal conchae (2) – walls of nasal cavities. Mandible (1) – lower jaw (only movable bone in skull) Vomer (1) – nasal septum  Facial Bones Palantine (2) – roof of mouth (hard palate)  Viscerocranium nasal lacrimal zygomati palatin maxilla Vomer Mandibule Concha nasalis inferior Anterior Posterior Nasal bone 7-13  Nasal bones The small, rectangular nasal bones join at the midline to form the bridge of the nose. Forms the superior margin of nasal aperture Fractures of the nasal bones or fragmentation of the associated cartilages are common facial injuries. Nasal bones  Nasal bones Articulates with Nasal bone of the opposite side Nasal portion of the frontal bone Frontal process of the maxilla Perpendicular plate of the ethmoid  Lacrimal bones The thin lacrimal bones form the anterior part of the medial wall of each orbit. Each one has a lacrimal sulcus - a groove that helps form the nasolacrimal canal. This opening permits the tears of the eye to drain into the nasal cavity.  The lacrimal Forms a small portion of the medial wall of the orbit. The lacrimal forms a small portion of the lateral wall of the nasal cavity 7-23  Lacrimal bones Articulates with Frontal process of the maxilla Orbital plate of the ethmoid bone Frontal bone Inferior nasal concha  Zygomatic Bones Irregularly shaped bones (cheekbones) that form the prominences of the cheeks and the inferolateral margins of the orbits.  Zygomatic Bones Temporal process Zygomatic process Zygomatic Bone Temporal bone Zygomatic arch  Vomer Vomer – plow-shaped bone that forms part of the nasal septum. Vomer  Vomer Articulates with ethmoid bone Articlates with \ sphenoid bone Articulates with septal cartilage Alae Articulates with maxillae and palatine bones Vomer (lateral view) Cavitas nasalis Septum nasi  Articulates with: Vomer The perpendicular plate of the ethmoid Maxilla Palatine Sphenoid bone Septal cartilage Posterior border does not articulate with any other bone  Inferior nasal conchae Inferior nasal conchae – paired, curved bones in the nasal cavity that form part of the lateral walls of the nasal cavity. Inferior nasal meatus  Palatine bones Palatine bones – two bone plates that form portions of the hard palate, the posterolateral walls of the nasal cavity, and a small part of the orbits and roof of the oral cavity.  Palatine bones 1. Horizontal plate: It comprises the bony core of the posterior quarter of the hard palate and a part of the floor of the nasal cavity. 2. Perpendicular plate 3. Three Processes: pyramidal process, orbital process, sphenoidal process ANTERIOR POSTERIOR Maxillary Bone  Maxillary Bone Medially fused bones that make up the upper jaw and the central portion of the facial skeleton Facial keystone bones that articulate with all other facial bones except the mandible These bones contain maxillary sinuses. Have different part: 1. Body 2. Frontal process 3. Zygomatic process 4. Palatine process 5. Alveolar process  Maxillary Bone Frontal Process Alveolar Processus Zygomatic Process Palatine Process  Maxillary Bone Palatine process Extends medially to form the majority of the hard palate Articulates with the palatine process of the opposite side and the horizontal plate of the palatine bone Incisive foramen is located in the anterior portion 7-55  Maxillary Bone Alveolar process The part of the maxilla that supports all of the maxillary teeth Extends inferiorly from the maxilla Each maxilla contains 5 primary and 8 permanent teeth. Alveolar bone is resorbed when a tooth is lost 7-54 Mandible 7-56  Mandible The mandible (lower jawbone) is the largest, strongest bone of the face. Described as horseshoe shaped. All muscles of mastication attach to the mandible 7-57 Mandible 7-58 Mandible Mental 7-59 foramen Mandible 7-60 Mandible 7-62  Mandible 1. Body Mental foramen Oblique line Mylohyoid line 7-64  Mandible 5. Alveolar process Extends superiorly from the Mandible body Created by a thick buccal and a thin lingual plate of bone The part of the mandible that supports the mandibular teeth Each side of the mandible contains 5 primary and 8 permanent teeth Alveolar bone is resorbed when a tooth is lost. 7-68  Hyoid Bone It is at the C3 vertebral level. It is located in the front of the neck. It does not articulate with any bone. In the anterior part of the neck, the upper and lower hyoid muscles attach to this bone. Hyoid Bone 7-70