Anatomy

• The cranium can be subdivided anatomically into the roof and base:

  • Cranial roof - comprised of the frontal, occipital and two parietal bones
  • Cranial base - comprised of the frontal, sphenoid, ethmoid, occipital, parietal and temporal bones
• Pterion:

  • H shaped junction between the temporal, parietal, frontal, and sphenoid bones
  • More susceptible to fractures - blow to the side of the head
  • Pterion overlies the middle meningeal artery
  • Can lead to extradural haematoma
• The cranial base bones can be divided into anterior, middle and posterior:

  • Anterior = frontal and ethmoid bones
  • Middle = temporal and sphenoid bones
  • Posterior = Posterior temporal and occipital bone
• Paired facial bones:

  • Zygomatic - cheek bones
  • Lacrimal - smallest, form part of the medial wall of the orbit
  • Nasal
  • Maxilla - upper jaw and hard palate
  • Mandible - jaw
• Sutures of the skull:

  • Represent points of potential weakness
  • Coronal suture - fuses the frontal bone with the two parietal bones
  • Sagittal suture - fuses both parietal bones to each other
  • Lambdoid suture - fuses the occipital bone to the two parietal bones