Simple Redirect I'm not Able To Get Working, please Help

Hi to all, I'm new here and quite a newbie with .htaccess issues.
I have got dinamic page indexed by Google with two different urls like
/?topic=177 and /?topic=177.0
It was my fault cause a bad link in a thread.
Now I need to redirect the first url to the second one, that is the standard for the script, and I just tried a simple redirect added at the end of my .htaccess, just redirecting notwww to www et index.php to root.

It doesn't work at all, the url isn't redirected.
Can you please help me?
I have other redirect like this on static pages that works perfectly, I suppose the problem is in the special characters ? = and .

Not a lot of help here!
BTW I solved my problem after a lot of work and research.
I just post here the solution for future reference, just in the case someone else my need that.
Only RewriteCond can read a query string and I have to use it
I have to use the ConditionPattern = to avoid an infinite loop (to avoid to rewrite 31.0)
This is the working code