While it may not seem necessary to you, someone attempting to heal your bones certainly wants to know if you smoke.
http://orthopedics.about.com/cs/brokenbones/a/smokingbones.htm
Smoking has a documented detrimental effect on the rate at which your bones (and skin) heal. Chances are the nurse didn’t care if you told her or not. You won’t get your follow up in the ER, but it is important for the doctor to decide when to schedule follow up appointments and your final cast removal.
Smoking has a documented detrimental effect on the rate SOME people heal.
The operative word here is some. Statistically it is true, but in real life the opposite is just as true.
BTW - the stitches came out earlier and the cast came off earlier than was originally estimated. Additionally I came out of the anesthesia following my surgery far sooner, and without any ill effects, than was expected and instead of having to spend the night in the hospital I was home in my own house less than 12 hours after surgery.
I don’t think a study of 54 patients is really conclusive of fact.