Diagnostic injection mystery

Hi, new to forum. Instead of starting with a novel about my inability to get a diagnosis for almost a year, I have a very specific mystery from my latest round of diagnostic injections. I'm looking for ideas.

I was injected about 10 locations in my lower right back (under fluoroscopic guidance); diagnostic injections only (no steroid). As I'm sure many know, these injections are horribly painful and stressful. There wasn't significant reduction in pain from any of them. Afterwards, on the drive home, at home, I was pretty much at my baseline pain level, with aggravating positions producing the same level of pain.

Then, about 4 hours later, about the time the numbing medicine should be wearing off, my chronic ab/back pain areas start ramping up. In the middle of the night, it woke me up, and it was comparable to the worst pain I have ever experienced with this condition - it was radiating, but it felt centered exactly in my chronic areas (back/ab) - which are very localized locations. Yes, I also had superficial pain from the injection sites, but the pain I'm talking about was deep, and shot through to my abdomen (in the same chronic pain localized area). For comparison, in the last year I've been through several diagnostic-only shots (hip, SIJ, etc), and only had mild internal post-injection discomfort from these shots.

The pain was significant all the way until I woke up Sunday morning, and now I'm pretty much back to baseline.

I have my own theories on what could have happened, but I wanted to see what others thought before biasing your response. I'm hopeful there is a clue in this pain that helps us finally figure this out.

My diagnostic spinal injections DID have steroid. If they worked for even a few days that was the indication that ablation would work.

Without steroid you wouldn't expect to have any reduction in pain beyond the time that the local anesthetic lasted. You would only get immediate relief in the area of where the nerve goes, and it would quit in minutes to hours depending on which anesthetic was injected.

I will preface my reply by noting that I have not undergone diagnostic lumbar injections, neither with steroid as an epidural nor with lidocaine as a stand alone agent (as you, the original posterr, are commenting on).

The question asked: Why a significant uptick in pain 4 hours post lidocaine injection?

You comment in your initial post that diagnostic injections are immensely painful in and of hemselves. If this is the case, then it stands to reason that the lidocaine provided soecific pain coverage of the injection sites immediately post procedure through the 4 hour mark post procedure. The lidocaine provided relief of the injection pain, leaving you with your baseline pain intact immediately post procedure and in the first hours following. The high spike in pain at 4 hours post procedure was the injection site pain giving you full notice when the lidocaine lost effectiveness. The sharp uptick in pain at 4 hours is the injection site specific pain where the lidocaine has lost effectiveness.

That's my take on your experience.
- K -