X-RAYS DON'T ALWAYS SHOW FRACTURES

 Laypeople, even physicians, often if not most of the time, labor under the UNTRUE notion that if someone receives trauma, x-rays (ie "plain films") that use equipment that has not changed much since 1895, and expose the patient to radioactive particles, will show whether the patient has a fracture / broken bone, or not...as if it is a grey Oracle of Delphi that always tells the truth.

Radiologists know that nothing could be farther from the truth. "Sometimes an X-ray will not show a fracture." https://www.webmd.com/a-to-z-guides/understanding-fractures-treatment#:~:text=Sometimes%20an%20X%2Dray%20will,)%2C%20or%20a%20bone%20scan.

https://healthcare.utah.edu/the-scope/shows.php?shows=0_wny3n8ot

"A possible occult fracture is a suspected broken bone that doesn't show up on X-rays. Accidents, repetitive injuries, and normal stresses on weak bones can all cause occult fractures. The pain from occult fractures gets worse with activity. MRI is one of the best tools for diagnosing occult fractures."

Of course, many US soldiers have sustained serious brain injuries, e.g. TBI or traumatic brain injury...most often without skull fractures. Another non-fracture involved brain injury is "diffuse axonal injury", also known as Shaken Baby Syndrome.