Anatomy Practical 1 Flashcards
Which are the cranial bones?
Frontal, parietal, occipital, temporal, sphenoid, ethmoid
Which are the facial bones?
Mandible, maxilla, zygomatic, nasal, lacrimal, palatine, vomer
What are the features of the temporal bone?
- petrous part
- zygomatic process -> zygomatic arch
- mastoid process
- styloid process
- external acoustic meatus
- internal acoustic meatus
What is the petrous part?
Thicker part of temporal bone
houses middle and inner ear
What passes through the internal acoustic meatus?
- vestibulocochlear nerve
- facial nerve
What is the zygomatic process?
Bar like part of temporal bone
Forms the zygomatic arch (cheek bone)
What is the mastoid process?
Anchoring site for some neck muscles
What is the styloid process?
Needle like
Attachment for tongue and pharynx
What are the features of the sphenoid bone?
Butterfly shaped
Articulates with all the other cranial bones
- central body, greater wings, lesser wings, 4 pterygoid plates
- foramen (5)
What are the 5 foramen in the sphenoid bone?
SOF Optic canals Foramen Rotundum Foramen Ovale Foramen Spinosum
What is the pterion?
Temple
Position of anterior branches of middle meningeal artery
Union of frontal, parietal, temporal, sphenoid bones
Skull at its thinnest point
Periosteum - groove which runs middle meningeal artery
What does the middle meningeal artery supply?
Dura and bone
When is middle meningeal artery impacted?
Intracranial haemorrhage
What are the features of the ethmoid bone?
Sieve through which air can pass
Cribiform plate on superior surface where olfactory bulbs of olfactory nerve sits
What are fontanelles?
Where bones of skull do not contact
Wide areas of fibrous tissue
Which bones contain air sinuses?
Frontal, sphenoid, ethmoid, 2 maxillary bones
What are paranasal air sinuses and what do they do?
Mucosa-lined air filled sinuses
Lighten the skull and enhance resonance of the voice
How many vertebrae are there in the spine and what are they separated by?
33
Intervertebral discs which act as shock absorbers
What are the common features of the vertebrae?
Body
Vertebral arch forming vertebral foramen where spinal cord passes through
Transverse and spinous process (attachment for muscles of back)
What is C1?
Atlas
vertebra which articulates with occipital condyles of the skull
What is C2?
Axis
Vertebra with a dens process, acts like a pivot, allows atlas to pivot around horizontal axis (shaking head to say no)
What is the sacrum?
Triangular Forms back of pelvis Formed by 5 fused vertebrae Laterally articulates with 2 hip bones forming sacroiliac joints Vertebral canal continues inside
What is the coccyx?
Triangular bone consisting of 4 fused vertebrae
What are the developmental parts of the brain?
Telencephalon (cerebral hemispheres) Diencephalon (thalamus, hypothalamus) Mesencephalon (midbrain) Metencephalon (pons, cerebellum) Myelencephalon (medulla oblangata)
What developments parts make up the forebrain, midbrain and hindbrain?
Forebrain - telencephalon, diencephalon
Midbrain - mesencephalon
Hindbrain - metencephalon, myelencephalon
What are the features of the midbrain on the ventral surface of the brainstem?
Short
Cerebral peduncles
What are the cerebral peduncles?
Massive bundles of nerve fibres descending from cerebral motor cortex to the brainstem and spinal cord carrying corticospinal tract
What are the features of the pons on the ventral surface of the brainstem?
Bridge like
Sharply demarcated
Ridged appearance
4 pairs of cranial nerves - CN V to VIII
Which cranial nerves are associated with the pons?
CNV-VIII Trigeminal Abducens Facial Vestibulocochlear
What are the features of the medulla on the ventral surface of the brainstem?
Medullary pyramids
Decussation for the corticospinal tracts
Inferior olive laterally
CN IX-XII
What cranial nerves are associated with the medulla?
CN IX-XII Glossopharyngeal Vagus Accessory Hypoglossal
What are the features of the midbrain on the dorsal surface of the midbrain?
2 paired swellings - inferior and superior colliculi
Buried beneath overlying cerebral hemispheres
CN III-IV
What is the obex?
1/3 of the way up the medulla
central canal
opening of the 4th ventricle
What is the function on the 4th ventricle?
Contains CSF that drains into the central canal of the spinal cord inferiorly and into the cerebral aqueduct superiorly
Where does the blood supply to the brainstem arise from?
Vertebral arteries
What do the internal carotid and vertebral arteries supply?
Internal carotid - anterior/superior of cerebrum
Vertebral arteries - posterior/inferior of cerebrum
What does the internal carotid divide into? What do these vessels supply?
Anterior cerebral in midline of cerebrum - lower limbs
Middle cerebral in lateral cerebrum - upper parts of body
What is the significance of the pontine-midbrain junction?
Basilar artery splits into the posterior cerebral artery