I’m sorry, I haven’t been to visit you. I broke my leg.

Basically, the speaker is telling another person a reason as to why they haven’t seen them recently.
Actually the punctuation is slightly wrong:
I’m sorry I haven’t been to visit you, I broke my leg.
Getting rid of that first comma helps the text to flow better. 
After saying that they are sorry, they give a reason in the simple past tense by saying I broke my leg.
Quite a good reason for not doing anything I suppose!