Why do doctors or radiologists miss a Scaphoid fracture?

Scaphoid fractures are not always clear, even on an x-ray.  Very often, patients present with no obvious injury, deformity, or swelling.  In the days and weeks following scaphoid fracture, the pain may dissipate, and the injury may be confused with a sprain.  More detailed imaging techniques are often required to diagnose a scaphoid injury.