Hello, I have been having lower back pain for 25 years. Now the pain is going down my left leg and it is becoming weak and numb. I have had 2 MRI's CAT Scans, x-rays, today a Meylogram and now the Doctor wants to do a discogram. I was told that my L5-S1 is a "shot" "black disc" and this is the cause for my pain, so why so many test. I am told that my pain should be down the right side instead of the left side...not sure what that means. Has anyone gone through all these tests and are they really necessary?