Infection would be more of a sterility issue then just hitting the bone.I bent a needle over once from hitting a bone,was sore and hurt for a while. What a mess pulling that pin out ,,,sheeez.
For injections others then glutes, you should be using 25g 1" pins. If injections procedures are followed correctly, you should have no worries about hitting any bones...........
wow, I've been through a lot of stress about this, but everything seems to be ok, thanks for the answers, I'll be more carefull next time, using a proper pin.