crps..or RSD as I will always call it. there is no real test and the bone scan shows .. some things not all.. did you get a three phase bone scan.. this is important.. a regular bone scan is an injection then an hour break and scan.. a three phase bone scan is the injection. immediate scan, then one hour then 3 hours.. (three scans) the triphase bone scan is what they "say" shows the RSD best.. but not always... so if you show once but not twice it is still RSD and bone density test is test to see if you have osteo.. it might show up on bone scan but I wouldn't count on it... this is all my personal experience. and conversations with dr,s. .. good luck to you I hope this helped