Flammable Bone Putty: Are We Missing Something (Or Rather Has Someone Else)?

J&J’s new acquisition Synthes, now folded into a division called Depuy Synthes, has found itself on the wrong end of a product problem with the news that its hemostatic bone putty is the subject of an FDA Class 1 recall notice because the stuff appears to run the risk of igniting in the presence of electro-cautery devices.

The FDA recall notice can be found here and runs through the usual routine of asking medical professionals to identify, isolate and return all product.

The material was FDA approved by 510(k) late last year, so it would seem the problem has evidenced itself fairly early in its life.

Two questions arise though, which none of the coverage we’ve found on the matter appears to address. Firstly why does this happen?… presumably there’s something flammable in there (duh!)?

And why wasn’t this flammable component or potential picked up earlier? Surely it’s pretty fundamental. The putty contains no active hemostatic agent, working by providing a physical rather than a blood clotting effect. It’s made from water soluble alkylene oxide copolymers combined with Carboxymethylcellulose(CMC) to improve handling and notably its predicate device, Ostene does not contain the latter constituent (and has not been recalled).

Indeed CMC, according to its material safety data factsheet is known to be flammable at high temperatures, which leaves it looking a tad guilty. Presumably on issuing its 510(k) clearance FDA didn’t consider the amount of the constituent to be significant enough to represent a significant difference to the cited predicate device, when it actually looks like in this case it was different enough to require a few extra tests (chap in white coat with a lighter, that kind of thing), which clearly didn’t happen.

Reassuringly it would appear that there have been no reports of the product actually being ignited in vivo, so a huge sigh of relief there, but this does seem to call into question the regulatory process a little.

Source: FDA