(1.2) Osteology Flashcards
What structures does the ligamentum nuchae (nuchal ligament) attach to? What is its function?
Attaches to the Occipital bone -> Posterior tubercle of C1 -> Spinous processes of C3 to C7 -> continues as Supraspinous and Interspinous ligaments from C7 to Sacrum
Function to preserve the normal curvature of the cervical vertebrae
Why is the facial nerve at risk of damage during a forceps delivery?
Newborns’ temporal bone is still not fully developed, leaving a small mastoid process, therefore the facial nerve is more superficially placed when it leaves the stylomastoid foramen
How are the cervical vertebrae different from the other typical vertebrae in the body?
- Spinous processes bifid
- Foramen Transversarium in Transverse Processes for Vertebral arteries to pass through
- Largest & triangular Vertebral Foramina
What are the names of C1 and C2? How are they and C7 different from the other typical Cervical Vertebrae?
- C1 = Atlas, has no Body or Spinous Process
- C2 = Axis, projects Dens that is held by Transverse (Cruciform) Ligament of Atlas
- C7 does not have Spinous Process
Which joint allows shaking the head? Which joint allows nodding the head?
- Nodding: Atlanto-occipital
- Shaking: Atlanto-axial
(Say yes before say no)
Why are the Cervical vertebrae prone to whiplash injuries?
The Articular Facets of the Cervical vertebrae are more horizontally aligned
What is a Jefferson fracture?
A vertical transmitted force either from the head or leg, on to EXTENDED neck, bursting the Atlas (fracture either or both superior or poster arches)
What is a Hangman’s fracture?
Hyperextension of the head & neck, dislocating the Dens of Axis to crush the brain stem -> unconsciousness/respiratory or cardiac failure/death
Why is a sublaxation between C2 & C3 life-threatening? What common cause may result this?
- Compression to the outflows of Phrenic Nerve (C3-C5), as each nerve root exits above the corresponding vertebra. This disable the diaphragm to contract during inspiration
- Whiplash/Hyperextended injury - head being whipped back on to shoulder e.g. due to car accident/rugby tackle
What is a suture? What are their roles?
Sutures = fibrous joints of the skull
Serrated edges & directions -> interlock bones, preventing fractures from a pressure in one direction
Where is the weakest point in the skull? What may a fracture of the point cause? How may it be treated?
Pterion = junction of Frontal & Parietal & Temporal & Sphenoid
- > the Middle Meningeal A (br. of Maxillary A) runs underneath, which supplies the Dura and the Skull. Its damage may lead to Extracranial Haematoma hence a raised ICP -> nausea, bradycardia, limbs weakness
- treated with Diuretics or if severe, Burr Holes are made
How are the neonatal bones different from the adult ones?
- Open Sutures = Frontanelles
- Small Facial skeletons
- Alveolar processes & Paranasal sinuses aren’t fully developed
What are the 6 main parts of the Temporal bone?
- Squamous
- Zygomatic process
- Tympanic
- Styloid process
- Mastoid process
- Pteromastoid
http: //teachmeanatomy.info/head/osteology/temporal-bone/
What is a dipole in the clavaria? What is its function?
- Dipole = Spongy layer (containing bone marrow) that separate the 2 compact bones in the clavaria
- Reduces weight
- Haemopoeisis
Which two sutures meet to form the Bregma? Which two form the Lambda?
- Coronal & Sagittal
- Lambdoid & Sagittal
