One was in his early 50's and playing tennis with his daughter. He went back for a lob and just tripped.

The other was a successful young engineer in his late 30's. He just tripped over a toolbox that was in back of him.

They both hit the back of their heads, and neither had any previously known health problems or attacks of vertigo.

I don't walk backwards as a rule. But I trip over all kinds of stuff (mostly the kids toys) walking forward.

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