Skull Fracture


Pathophysiology

Diagnosis

Linear Skull Fx

  • Caused by low-energy blunt trauma over wide surface area
  • Runs through entire thickness of bone
  • More significant injury if
    • Goes through vascular channel
      • Can cause epidural hematoma
    • Goes through venous sinus groove
      • Can cause venous sinus thrombosis
    • Goes through a skull suture line
      • Can cause suture diastasis
  • Clinical Features
    • Many patients are asymptomatic
    • Many patients have NO loss of consciousness
    • Swelling noted at site of impact
    • Skin may not be violated
  • Treatment
    • Conservative
    • Must R/O brain injury
    • Consult trauma, neurosurgery
    • Some patients may be discharged home

 

Basilar Skull Fx

  • Linear fracture of base of skull
  • Usually has associated dural tear
  • Found at specific points of skull base
  • Temporal skull Fx
    • Longitudinal (most common)
      • In temporoparietal region
      • Involve squamous temporal bone
      • Run anterior or posterior to cochlea/ labyrinth capsule
      • End in middle cranial fossa or mastoid air cells
    • Transverse (5-30%)
      • Start at foramen magnum
      • Extend through cochlea and labyrinth
      • End in middle cranial fossa
    • Mixed fractures
      • Show elements of both types
  • Occipital condyle fracture
    • Result from high-energy trauma
      • Trauma with axial compression, lateral bending, rotation w/respect to alar ligament
    • Three types
      • Type 1: Comminution of occipital condyle
        • Results from axial compression
        • Stable fracture
      • Type 2: More extensive injury
        • Results from direct blow
        • Stable (alar ligament/ tectorial membrane intact)
      • Type 3: Avulsion injury
        • Results from forced rotation/ lateral bending
        • Potentially unstable fracture
  • Clinical features of basilar skull Fx
    • Petrous bone Fx:
      • CSF otorrhea and Battle's sign
      • May see hemotympanum
      • Loss of consciousness and GCS are variable
    • Anterior cranial fossa Fx:
      • Raccoon eyes
      • CSF rhinorrhea
      • Loss of consciousness and GCS are variable
    • Longitudinal temporal bone Fx
      • Ossicle bone disruption
      • Conductive deafness (>30 dB, lasts > 6-7 weeks)
      • May see CN symptoms
        • V - facial palsy
        • VI - nystagmus
        • VII - facial numbness
    • Transverse temporal bone Fx
      • Involve CN VIII and labyrinth
      • Nystagmus, ataxia
      • Permanent neural hearing loss
    • Occipital condyle Fx
      • Very rare, very serious
      • Most patients are in coma (esp. Type 3)
      • Most have associated c-spine injuries
      • Often have lower CN injuries
      • Often have hemiplegia or quadriplegia
      • Vernet syndrome
        • Involvement of CN IX, X, XI
        • Trouble phonating
        • Risk of aspirating
        • Ipsilateral vocal cord, soft palate paralysis
        • Ipsilateral sternocleidomastoid and trapezius paralysis
      • Collet-Sicard syndrome
        • CN IX, X, XI, XII involvement
  • Treatment
    • Usually conservative
    • MUST R/O brain injury
    • AVOID nasal intubation with CSF rhinorrhea
    • NO NG tube
    • Consult trauma/ neurosurgery
    • Elevate head of bed if CSF leak is present
    • Antibiotic prophylaxis
      • NOT recommended for CSF otorrhea/ rhinorrhea in first week
      • If fever, etc - consider meningitis
    • If CSF leak persists >10 days, OR repair is needed

 

Depressed skull Fx

  • Come from high-energy blunt trauma to small area of the skull
  • Most are over frontoparietal region
  • To be clinically significant/ require elevation:
    • Bone should be depressed greater than adjacent inner table
  • May be closed or open
    • Open Fx:
      • Scalp laceration overlying fracture OR
      • Fracture runs through paranasal sinus/ middle ear structures
        • Results in communication with the external environment
  • Treatment
    • Admit for observation
    • R/O brain injury
    • Trauma/ neurosurgery consult
    • Prophylaxis for post-traumatic seizures
      • Phenytoin
        • Load: 15-20 mg/kg IV (give at < 50 mg/min)
        • May follow with 100-150 mg after 30 min
    • May require surgery for fragment elevation

 

Fracture/ Suture Differences

  1. Fractures
    • Usually > 3 mm wide
    • Widest at center, narrow at ends
    • Appear dark
      • Go through inner and outer bone lamina
    • Usually in temporoparietal area
    • Usually run in straight line
    • Any turns are usually angular
  2. Sutures
    • Usually < 2 mm wide
    • Same width throughout
    • Lighter in appearance
    • At specific anatomic sites
    • Do NOT run in straight line
    • Have many curves
    • Relatively symmetric (w/compression to contralateral side of a head)