I've done the same thing, or about. I've got a 3 level home. I was walking and looking at an index in a book at the same time and missed the top step. Thought it was one step out further than it was. I tumbled half of the way down, and caught myself in a strange position. Hurt my left shoulder, but didn't know it for about a year later, when it finally started to hurt. Then I missed the bottom 2 steps and tumbled all over again. Now I pay a lot more attention to what I'm doing.

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