Interpreting Skull Fractures and Their Causes

In an earlier blog post I addressed concussion and the specifics of brain injury. This blog post focuses on a related topic: skull fractures. This broad term represents an extensive list of 20 specific types of fracture, each with its own etiology (cause) and description. Most fractures can indicate a fall, motor vehicle collision, or other impact to the skull, but some connote assault. Determining the potential cause of a skull fracture can be an important factor in your case. Use the following list to help sort the complexities of skull fracture.


Type of Fracture

Fracture Description

Fracture Etiology/Causes

Basilar Linear fractures on the skull floor (base) Multiple etiology
Blowout Fracture of the floor of medial wall of the orbit (eye bone) into the sinuses; orbital rim is intact Sudden blow to the eye pushes the intact globe (eyeball) back into the orbit
Comminuted Multiple fragmentation due to crushing injuries Low velocity/high impact
Coup At the site of impact Direct force
Contrecoup/Remote Away from the impact site Crushing injuries; indirect force transmitted through the moving brain
Closed/Simple Skin is not broken or cut; no exposure to external environment Multiple etiology
Dentoalveolar Separation of mandibular fragment that may contain teeth Direct force applied anteriorly or laterally
Depressed Inward displacement of bony fragments Affects children under three years
Diastatic Occurs along the suture line of the skull High velocity; caused by forces with low mass
Hairline/Fissure Straight discontinuity of bone Multiple etiology
Hinge Longitudinal or transverse crushing injuries Multiple etiology
Le Fort I Separation of all or a portion of the midface from the skull base Impact to face
Le Fort II Maxilla may be separated from the face; fracture extends into the orbits through the interorbital region Impact to face
Le Fort III High horizontal maxillary fracture through the nasofrontal suture, through the medial orbital wall and frontozygomatic suture, across the arch and through the sphenoid Impact to face
Linear Fracture in a straight line with no bone displacement Low velocity caused by forces with large mass
Open/Compound The skin is broken, and the bone is in contact and visible with external environment Multiple etiology
Pond Shallow depressed fractures Continuation of linear fractures or compression
Plug Outer table of the bone is intact; the inner table is broken out Low velocity impact with a small surface
Ring Circular fracture around the foramen magnum (base/floor of the skull) Compression of lumbar spine after fall landing on feet or buttocks
Stellate Star-shaped injuries Multiple etiology