Final answer:
In an epidural bleed, fractures often occur in the bones near the pterion, commonly involving the temporal and parietal bones. Less commonly, the sphenoid bone might also be affected due to its proximity to the pterion.
Step-by-step explanation:
An epidural bleed is typically associated with a fracture that affects the arteries within the skull. In relation to the pterion, an area where multiple skull bones come together, a blow to the lateral side of the head can lead to a fracture of these bones. The temporal bone, which bounds the parietal bone inferiorly and is located near the pterion, is often involved in such injuries. Additionally, the fracture might extend to involve other bones such as the parietal bone, and less commonly, the sphenoid bone, that are also in the vicinity of the pterion.