I have 3 clients with the 'biologic disc sealant' injections with mixed results. It's very interesting and may be worth trying for the good candidates.
Unfortunately, the school of hard knocks that I mentioned in another thread came on my wife's case. If you look at her imaging on
her GPN story page, you'll see that her disc is really severely compromised. I don't have her full MRI, but the sagittal images shows buckled annulus across the entire back of the disc. The chance for long-term success from the endoscopic-d was probably not so great. (My apologies... her story page needs updating. She had a wonderful result fo 2.5 months, then started having radicular pain on the other side. She had a 2-level ADR in March 2008 and is not back at work full-time as RN, now almost 8 months post-op. Newer info in
her surgery blog.)
Regarding chemical irritation of the nerve roots... I agree that many surgeons pooh-pooh the idea, much like most used to pooh-pooh discogenic pain and discography. (Same problem exists w/piriformis syndrome and so many other bastard diagnoses.)
I was in the OR with Tony Yeung and he said something like, "Look here Mark, do you see the way the nerve root is all smooth and red. This patient has very little fat insulating the nerve root. He can have what appears to be a minor disc protrusion that is not distorting the nerve root and must surgeons will look a the seemingly benign MRI and not believe that this is the problem." Later in the day, he showed me the same nerve on a different patient. "You see all the fat surrounding the nerve? This patient can have a substantial herniation with substantial compression of the nerve and have no symptoms or more minor symptoms than one might expect based on the MRI." The pictures do not always tell the story.
Dr. Yeung also talks about "interpositional disc tissue" as a reason for discectomy to fail. A fragment of nucleus material that is stuck in the annular tear will keep the tear from healing and will 'wick out' the neurotoxic juices that are produced in the disc. This is one of the advantages of SED. Working visually from inside the disc, he can see the annular tear and he can also see how the annulus responds to the thermal annuloplasty as he is watching it as he applies energy to it.
Gotta run... Thanks for the post. The discussion of chemical irritation is very interesting and I hope this helps.
All the best,
Mark