[Just another Joe]

"David was about to shave when he hit his head on a shelf, which shattered. His hand was cut quite badly."

So, while shaving he hit his head on a glass shelf hard enough to shatter it and hurt his hand?

[1rudeboy]

I can see it . . . he might've knocked it off the wall with his head, and cut himself trying to catch it as it fell. It might've broken on the sink, etc. I once had a similar accident with a beer bottle.