A traumatic head injury isn't a policy position.

When I heard about Clinton's concussion, it seemed perfectly plausible that a 65-year-old woman who'd been vomiting because of a stomach virus could get dizzy, pass out and hurt her herself, even without immediately recognizing the severity of the damage.

The federal Centers for Disease Control reports that falls cause half the traumatic brain injuries among children aged 0 to 14 and 61 percent of those injuries in adults 65 and older. (1.usa.gov/hwa306)

When I heard she had a blood clot, too, I immediately recalled December 1993. That's when my father, then 62, fell in the bathroom at home and hit his head. He didn't feel well after that and went to his regular physician, who diagnosed a sinus infection.

No one who saw my father daily (I was living in Washington, D.C., at the time) recognized that changes in his personality signaled something more serious. When my younger sister came from Houston for Christmas and realized that he wasn't making sense, she insisted he go to the hospital. Surgery for a subdural hematoma, a collection of blood on the brain surface, almost certainly saved his life that Christmas. It was a frightening time, but we were blessed. He celebrated his 81st birthday in November.

Clinton was diagnosed with a less-common condition, a transverse sinus thrombosis, which is a clot behind the ear in a major vein that drains blood from the brain. She hasn't needed surgery but instead was put on anti-coagulants to help dissolve the clot, according to news reports.

On Wednesday, The New York Times reported Clinton's medical team as saying that she was "making excellent progress" and that they were "confident she will make a full recovery." (nyti.ms/S5sk3z)

Reports haven't indicated what kind of rehabilitation she'll need or how long it will take. It's also not clear whether the concussion caused the blood clot or the blood clot caused some of her earlier symptoms. That might be impossible to know, and maybe that part is only for her and her family to know.