Post prostatectomy long term low back pain

I had a radical prostatectomy almost 5 years ago.  I have a PSA of zero.  I noticed after my first post operative digital rectal exam I experienced a reccurance of low back pain for the next couple of days.  I figured it was caused by the doctor's finger pressing on the nerves in the area.  As the back pain went away in a couple of days I did not think about it further.  Subsequently I noticed that bike riding produced the same low back pain and a dull ache above the parineum.  These days I have the back ache anytime I sit in a chair that applies presure to the parineum.  The back pain is a 7 on a scale of 1 to 10.  I am thinking of scheduling a visit to my urologyst to have him check it out with ultrasound.  I am thinking there may be scar tissue growing or something else.  Should I be concerned?

I had surgery three months ago - my lower back started bothering me about a month ago - but I never linked my back pain to the surgery until I read this.

 Another note to myself for the Dr.- see if back pain is related to prostate surgery.

 

Thanks,