Question from PhD student coming to SPRI

Thank you, Dr. Corenman.

Just a few more questions to clarify…

If an interbody fusion is not done in, say, the C-spine and the discs are left intact, and morselized laminectomy bone from other regions such as the T-spine is packed into central regions of cervical lamina (those that are remaining) and also packed into decorticated facets to create the C-spine fusion, my curiosity is why some of this bone cannot be ground off to restore movement ability over motion segments.

I understand that grinding on or otherwise “roughing up” a bone surface promotes osteoblast activity and the synthesis of more mineral bony matrix, but if bone creating the fusion is ground off the facets and the lamina that remain, can a barrier that inhibits the bone growth be placed over the areas from which the bone was ground off? Can a bone wax, in other words, be used, and if the facets have been decorticated can they be remodeled and/or remobilized? I assume that decortication of the facets does not entirely destroy the actual facet joint surfaces themselves?

Maybe I just need to come observe some surgeries, haha! That would be really helpful.

My Best,
Kendra

Thank you for this information Dr. Corenman. Very interesting! I truly appreciate your continued time and consideration in responding to me.

Do you think that bone marrow aspirate or PRP injections into the decorticated facets could help restore motion if the fusion was not done many years ago…or would it be a lost cause?

I would be very interested to hear your ideas about replacing cartilage on articulate surfaces, that is VERY much in line with some of my passions.

I do realize that surgeons have a generally reliable and extremely widely implemented treatment modality in fusion; however, I think that as medicine progresses we can do better to treat degenerative pathologies and trauma to the spinal column while preserving more of the innate qualities and function of the spine. Right now, to treat a given problem we obviously eliminate the natural function of these joints by fusing, and fusing itself can potentiate other problems. I have met many people who say they are more dissatisfied after their fusion than before, and wish they would never have gotten it done. Of course, I recognize this is not the case the majority of the time, but my empathy still lies with these folks. This is what piqued my interest in regenerative medicine: I wanted to spend my career working toward the goal of designing modalities to reconstruct bone, cartilage end plates and discs from a biological basis (i.e. pluripotent, multipotent stem cells). My ultimate hope is that one day, the acutely injured or diseased site itself can be directly treated and/or actually replaced with tissue-engineered constructs that do not lend themselves to concerns of immunogenicity, thereby bypassing the need to fuse the site(s) of concern in addition to subsequent levels.

At this point, I have learned that the mechanics of the spine are very complex, and that the practical surgical implementation of some of these therapies I aspire to work on is clearly a tremendous part of the equation. What good is it to work on developing some novel treatment if it cannot be practically applied, right. Hence, I am considering going to med school after I finish the doctorate to eventually get into spine surgery – I would want to continue to actively engage in research during my career as a spine surgeon, perhaps working in a large research-intensive academic setting. Based on all your experience in this elite industry, do you find that most novel research focused on the spinal column is derived from spine surgeons who have a research component to their career and/or are partnered with large medical device corporations?

I am very, very passionate about advancing options in spine surgery, so your opinion on this front (sticking with just the PhD or moving on to a 10-11 year track in med school to become a spine surgeon) would be of great value to me as well. I know that being a surgeon would give me a much, much deeper understanding of what is needed in conjuring research designs, and likewise impart a concise ability to judge the practicality of potential therapies in real-world application. I feel the doctors in the OR who are hands-on with these complex cases day in and day out are best equipped to design the next generation of therapies…who would know better than surgeons such as yourself?

What is your appraisal of this article?
http://www.drkennethlight.com/blog/dr-light-performs-the-first-spinal-fusion-reversal-in-the-u-s/

Again, thank you so much for all your input and the information.

My Best,
Kendra

PS – There is a contractual hang-up that has prevented some of us from moving up to Vail thus far, but I am hopeful that it will be resolved by the end of the year and we can come on up after that. I would be very pleased to meet you in person.

Thank You Again!
Kendra