Dissolvable Glass For Bone Repair

gpronger writes "Sticks and Stones May Break My Bones, but Glass Will Certainly Mend Them! The old schoolyard ditty may be changed to reflect developments using metallic glass that will dissolve in situ instead of the traditional stainless steel or titanium hardware, which require removal by surgery once the bone has healed. Physics World reports that researcher Jörg Löffler at ETH Zurich has created an alloy of 60% magnesium, 35% zinc, and 5% calcium, molded in the form of metallic glass. Through rapid cooling, the alloy forms a molecularly amorphous glass that slowly dissolves over time, supporting the injury long enough for healing, then slowly dissolving away."

Comments

I'm involved in something closely related.

[blind biker]

My group is cooperating with a startup that makes, among other things, glass microbeads covered with nanoparticles of whose composition I am not allowed to speak. These nanoparticles cause bone cell growth. In fact, they cause stem cell differentiation into osteoblasts, which I think is beyong cool. The glass slowly dissolves in the body and the bone remains. Our hypothesis (backed by some experimental data) is that these beads will restore fractured bones, such as spinal vertebrae, to patients with extreme osteoporosis.

Rarely have I wished success to a company, as in this case. Perhaps seeing my aunt succumb to multiple spinal fractures scared the shit out of me.

It won't replace casting

[ShooterNeo]

Unlike in a certain X-men movie, this "metallic glass" is NOT going to be injected into living human bodies while molten. It'll be carefully forged in a factory into parts that are currently made out of steel or titanium : various plates, screws, and other orthopedic hardware. For injuries that require surgery, orthopedic surgeons would use these metallic glass parts instead of what they currently use.

The problem is obvious : it's doubtful that this alloy will be as strong as steel or titanium, and so the screws or plates would have to be thicker and heavier to have the same strength. There's an obvious tradeoff : do you make a bigger incision and drill out bigger holes in the bone to use this dissolvable metallic glass, or do you use conventional hardware? Also, undoubtedly there will be decades of debate over whether the trace minerals leached into the body cause harm or not.

Bottom line : even if this technology turns out to be safe and effective and is approved for use, it will probably be decades until it is used most of the time.

Re:It won't replace casting

[evanbd]

Trace minerals aren't a problem. These aren't trace amounts. You'll notice the choice of metals: calcium, magnesium, and zinc are all things your body needs in non-trace quantities, and is capable of regulating the level of. A few tens of grams of metal, dissolving over a month or two, is a couple hundred mg per day. That's roughly comparable to the FDA recommended daily intake. It would be a lot like taking a extra multivitamin or two a day.

Re:end to casts?

[fuzzyfuzzyfungus]

I'd be extremely surprised if it did.

Casts are annoying; but they are dirt cheap, can be performed with comparatively minimal training, and are pretty low risk. For bone breaks that are easily accessible and not too complicated, they are going to be hard to dislodge.

This stuff would, if it works, turn a two surgery process(one to implant, one to explant) for dealing with nastier sorts of bone breaks into a one surgery process. That would be a win. Turning a zero surgery process into a one surgery process would be a major loss.

Re:end to casts?

[blueZ3]

Yep. I was going to comment that I have a 10" piece of titanium in my leg from a motorcycle accident, and at my 1-year followup appointment, there was no talk of removing it. I believe that these days they tend to leave the hardware in unless it's causing problems.