osteology of head and neck and its applied aspects
TRANSCRIPT
OSTEOLOGY OF HEAD AND NECK
SKULL JOINTS
SERRATE SUTURE (SAGITTAL)Present between two parietal
bones
Between parietal bones and
occipital bone
DENTICULATE SUTURE
PLANE SUTUTRE
Between two palatine bones
ANATOMIC POSITION OF SKULL
METHODS OF STUDY OF SKULL
SUPERIOR VIEW OR NORMA VERTICALISPOSTERIOR VIEW OR NORMA OCCIPITALISANTERIOR VIEW OR NORMA FRONTALISLATERAL VIEW OR NORMA LATERALISINFERIOR VIEW OR NORMA BASALIS
EXTE
RNAL
LYIN
TERNALLY
CRANIAL VAULT
CRANIAL BASE DIVIDED INTO 3 CRANIAL FOSSASANTERIORMIDDLEPOSTERIOR
NORMA VERTICALIS
BRACHYCEPHALY- FLATTENED HEADPREMATURE BILATERAL FUSION OF
CORONALSUTURES
ASSOSIATED WITH SYNDROMES SUCH AS APERT SYNDROME
CARPENTER SYNDROME CLEIDOCRANIAL DYSOSTOSIS.
DOWNS SYNDROME.
PLAGIOCEPHALY- SKEW HEAD.DUE TO UNILATERAL FUSION OF
CORONAL SUTURE
SCAPHOCEPHALY OR DOLICOCEPHALY – ELONGATED HEAD
DUE TO PREMATURE CLOSURE OF SAGGITAL SUTURE.
ASSOCIATED WITH SYNDROMES LIKE CROUZON SYNDROME AND MARFAN
SYDROME
TRIGONOCEPHALY- TRIANGULAR HEADDUE TO PREMATURE FUSION OF METOPIC
SUTURE.
OXYCEPHALY-HIGH HEADDUE TO PREMATURE CLOSURE OF CORONAL
SUTURE, PLUS LAMBDOID SUTURE
NORMA OCCIPITALIS
NORMA FRONTALIS
The metopic suture is always present at birth but usually disappears at 6-7 yrs. ( metopon= forehead)
The metopic suture may persist throughout life and be mistaken for a fracture
The paired frontal sinuses are posterior to the superciliary arches, between the upper and inner tables of the frontal bone.
Each usually underlies a triangular area on the surface of the face, its angles formed by the nasion, a point 3 cm above the nasion and the medial one-third and lateral two-thirds of the supraorbital margins.
They are rarely symmetrical The average dimensions of an adult
frontal sinus are height 3.2 cm, breadth 2.6 cm , depth 1.8 cm.
They open into anterior part of corresponding middle meatus or medial to hiatus semilunaris.
They are rudimentary or absent at birth , generally well developed between the seventh and eigth years, but reach full size after puberty.
Frontal air sinuses
Frontal bossing
Blow out fracture of the orbit
Maxilla ossifies in membrane from three centres One from maxilla proper and Two from premaxilla.
The centre for maxilla proper appears above canine fossa during the sixth week of intrauterine life.
Of the two premaxillary centres, the main centre appears above the incisive fossa during seventh week of intrauterine life.
The second centre appears at the ventral margin of nasal septum during tenth week and soon fuses with the palatal process of maxilla.
Ossification of maxilla
a) Fronto-nasal buttress
b)Malar-zygomatic buttress
c) Pterygoid buttress
Vertical trajectories of force
The largest of the paranasal sinuses and completely fills the bodies of maxillae
Pyramidal in shape Innervated by infra-orbital and
alveolar branches of maxillary nerve
Drains in middle meatus through hiatus semilunaries
The size of the sinus is variable. Average measurements are
Height- 3.5 cm Width-2.5 cm anterioposterior depth- 3.5 cm Clinical note: Extraction of upper
teeth might lead to fistula formation and sinusitis
Maxillary sinus
The mandible is the second bone , next to the clavicle , to ossify in the body.
Its greater part ossifies in membrane.
The parts ossifying in the cartilage include the incisive part below the incisor teeth, the coronoid and the condyloid processes, and the upper half of the ramus above the level of the mandibular foramen.
Each half of the mandible ossifies from only one centre which appears at about 6th week of the intrauterine life in the mesenchymal sheath of Merckel’s cartilage near the future mental foramen.
Ossification of mandible
• From beneath the teeth trajectories join together in common pillar- ends at condyle.
• Mandibular nerve and canal are protected• Trajectories from sympysis, gonial angle and coronoid process
join this main pillar.
Mandibular fractures
Facial bone fractures result from direct trauma and usually follow one of only a small number of
patterns. Some search patterns can aid in the interpretation.The eye follows these lines to check
these common fracture patterns.
McGrigor-Campbell lines
Campbell's and Trapnell's lines
NORMA LATERALIS
keens Transoral approach
Elongation of styloid process in eagles
syndrome
Gilles Temporal approach
NORMA BASALIS
Pharyngeal tubercle
Anterior part of norma basalis
GUERIN’S SIGN
TREATMENT SCHEDULE
Latham appliance
Vanderwoude syndrome
Middle part of norma basalis
posterior part of norma basalis
Foramen magnum
Jugular foramen
INTERNAL SURFACE OF CRANIAL VAULT
INTERNAL SURFACE OF BASE OF THE SKULL
Anterior fossa
Cibriform plate of ethmoid
Racoon eyes Rhinorrhea
ANTERIOR CRANIAL FOSSA
Middle cranial fossa
Sphenoid bone
Foramen LacerumStructures passing whole length:1. Meningeal branch of Ascending pharyngeal artery2. Emissary vein3. Internal carotid artery4. Greater petrosal nerve
Sphenoidal air sinus
The sphenoidal sinuses are two large irregular cavities within the body of the sphenoid and therefore lie posterior to the upper part of nasal cavity.
At birth the sinuses are minute cavities, and their main development occurs after puberty.
The average adult dimensions are vertical height 2cm, Transverse breadth 1.8 cm , anterioposterior depth 2.1 cm.
MIDDLE CRANIAL FOSSAHemotympanum CSF leak ottorhea
Foramen magnum
Jugular foramen
Posterior cranial fossaBattle’s sign
Bruising over sub-occipital region Cranial nerve injuriesDouble ring sign- Fluid from ear or nose placed on filter paper and a halo of double ring may be seen.
HYOID BONE
Attachments to hyoid bone
CERVICAL VERTEBRAE
Typical cervical vertibrae
Atlas
Axis
Seventh cervical vertebra