a couple years ago i put out the word at the local golf course about the good results i had using birkenstock inserts. in about 2 months, 13 people had experienced real relief; w/ their lower back, and their golf shoes. they all had troubles distributing their weight evenly on their feet. i have had custom made orthotics (podiatrist) and they are superior; but if your problem does not involve real pain, you might want to try the birk's.
also, find an honest shoe salesman and have your foot sizes checked very carefully. i was in my 30's before i looked at all my shoes and wondered why my right shoe had a very pronounced wear pattern--outside of heel worn down while inside looked new. i found that my right foot is just a bit more than a half-size smaller than my left. sorry to be so long-winded.....................b