Saturday, February 6, 2010

Spine Blogger Alert - Who Dat Graft Material

Recently, there has been a rash of promotional articles regarding the field of biologics. Any reader that is a skeptic must acknowledge that one has to wonder what the underlying motivation is of those writers that are proponents of marketing this arena as the new frontier in spine. Understandably, it's difficult getting excited about another screw, plate or piece of PEEK. Could it be that these thespians truly understand the science and therefore can lay claim to substantiate the efficacy of these technologies? Could it be that they have an investment in some of these companies and are looking to further commercialize a specific company's technology? Or, could it be that this is a segment that needs definition.

Every company in this sector claims that their product is better utilizing biologic and synthetic buzz words like mesenchymal stem cells, demineralized bone matrix, tri-calcium phosphate, silicate substituted calcium phosphate, allograft with stem cells, bone morphogenic proteins, osteoblast mitosis, osteocyte differentiation, to name a view. So in the spirit of debate, TSB wants to know what are readers believe is the best biologic product in the market versus the best synthetic by substantiating its efficacy? And please, do not quote any cervical fusion studies because we all know that you can spit into the C-Spine and it will heal.


  1. TSB, posing a question like this is like asking Obama what car I should drive. "We here at GM have a WONDERFUL selection of the best vehicles on the planet!" We are all blinded by whatever flavor of kool-aid we have been chugging. The truth is that you were close to hitting the nail on the head when you said that this segment needs further definition. I think that each of these technologies brings something unique to the table, but they all try to oversell themselves and try to tackle almost every indication. This is where we lose the very little science that we actually have, and it becomes what you termed as a "whore's market."
    Excellent blog - keep em' coming!

  2. rhBMP-2 is the only biologic bone graft option in spine that has multiple prospective randomized trials published showing it can get equivalent fusion results with iliac crest bone. There are safety issues related to dosing and it has not been studied in every indication. There is no other bone graft that has been as thoroughly studied and utilized by spine surgeons. The success and expense of rhBMP-2 has created the market for all the other overpriced and under researched bone graft options out there.

  3. So the question must be posed; If dosing is a major concern considering that many surgeons failed to report the early complications associated with this product, i.e. boney ingrowth into the canal etc., TSB must ask our readers is this product a biologic or is this a pharmaceutical? Considering that this product was developed by a pharma company one has to wonder? Besides, just because it walks like a duck, and talks like a duck, doesn't necessarily mean that it is a duck.

  4. Wow, broad subject! Let's try...

    Autograft, especially cancellous iliac crest: gold standard.

    Allograft: works reasonably well, immune response by patients underappreciated and rarely recognized, infection risk can never be and is not zero.

    DBMs: allograft that lost its structure (osteoconductivity), minimal amounts of growth factors, the additives in most cases do not recreate a viable osteoconductive structure. Same immune response issue, infection risk still not zero. After 20 years still almost no clinical data.

    The first, calcium sulphate, no structure and too rapid dissolution. The second, marine coral, HA coated, no dissolution or almost no resorption. Prospective studies show soso results.

    The other 250:
    HA based, almost no resorption, remain as foreign bodies inside bone, not ideal. Don't know of any prospective studies, so so results.

    TCP based ones do dissolve, be it slowly. Resorption occurs after dissolution has broken the material down to sufficiently small parts.
    So far seems the most appropriate and well understood base material. A few prospective studies have been published, with reasonably good results.

    BCP is a mix of the two, with the specific characteristics of each.

    Collagen addition to any of these: improves handling, may add something to the biology, but no data to prove it.

    Silicate or Bioactive glass addition: useful if done correctly, i.e. in the right quantity and with the proper dissolution curve. (0.8% Si encased in insoluble HA is not the way to go).

    PLGA based ones al suffer from the lowering of the pH and the resulting inflammatory response, no specific advantage.

    Hyaluronic acid: no track record regarding bone formation, not even in the lab.

    Bamboo or balsa wood: the next new new thing?

    Synthetics are tissue engineering scaffolds. These scaffolds also need to possess a number of specific physical characteristics. These vary widely among the 250 odd products, and few appear optimized from that perspective.

    Bone marrow: extensive literature showing it works, autologous, however may be difficult to get in elderly patients.

    Donor MSCs: Still loads of question marks; immune response, cell survival, proper differentiation??? No clinical data. Very expensive DBM? Rushed to market.

    BMPs: The real deal, they stimulate bone formation. Yet, they also stimulate a host of other biological processes and not all of these are yet well understood. Requires optimized carrier (not a collagen sponge). Very expensive. To be used with extreme care and only in 'hard core' cases. Unfortunately sold based on oversimplified informatio. Both early users and the company sat for a long time on very important information regarding potential side effects. MM, the problem is that the product was reviewed as a device, with some input from CBER, but not primarily as a biologic.

  5. Other than bmp-2, minimal good data. But why would companies bother to spend money on good prospective trials as long as our colleagues are willing to throw in, with little to no data, whatever their reps are pushing that week? We know this is true. I have had numerous reps admit that most surgeons never bother to ask for any supportive data on their products.

  6. Autologous materials have always been the best materials to use... better known as the gold standard. However most synthetics in proper configuration will work if properly loaded with high concentrations of autologous cells derived from bone marrow or adipose tissue. Proper fusion bed preperation is key. Can't make a pile of money on this, maybe that's why we have such confusion. BMP has it's place, but way overblown. For a non-biased view check out the paper from Future Medicine, Regen.Med (2009) 4(6). 783-785

  7. Bone Marrow Aspiration is the key and can make any synthetic osteogenic and osteoinductive to a certain degree. In all reality most synthetics are really just an osteoconductive scaffold and the introduction of the osteoprogenitor cells and everything else contained in BMA is what gives it those 2 other features. Even if the rep or company claimed you didn't need BMA, I'd still take it (from the vertebrae directly or the crest) to ensure I have checked off as many boxes as possible. Decortication of the transverse process to get some nice bleeding bone and proper cleaning and cutting up of local bone (taken during laminectomy, etc.) to accompany the synthetic are good practices as well. Just my 2 cents. As far as my preference...If I'm a patient, I'd probably want something that doesn't include a strangers donated parts.

  8. MM, regarding your question about rhBMP-2 and "device vs. drug" - in a number of companies outside of the USA, both Infuse and OP-1 are considered drugs and approved as such.

  9. whoops......countries

  10. Best biologic and best synthetic? The only ones with real data, e.g. Infuse and Vitoss. Best graft? Autograft.

  11. Vitoss? Turns to dust when you pack it in a void. Then again as I remember, Orthovita has not turned a profit since its inception.

  12. I have heard this too about Vitoss but a lot of guys are squirting BMP on it because of the collagen; is this useless seems like the stuff would just resorb faster?

  13. Does it really matter? many of us could have scrub techs open up a jar of JIFF peanut butter on the backtable and mix that in with autograft. the surgeons would neither care nor notice

  14. All synthetics turn to dust if they are applied with the usual orthopedic finesse. That's one of the reasons collagen is added to them. Once you truly understand the biology, you don't pack it that way.

  15. Try Equivabone. The only hard setting, conductive, and inductive biologic in the universe, and cleared for use in the disc space. At least according to their vp. A low cost alternative to Infuse. Sign me up.

  16. Bacterin OsteoSponge is the only bone I would use.