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HydroxyApatite Porous PEEK at the State of Spine Surgery

By February 24, 2020No Comments

Dr. Ryan Roeder presents HydroxyApatite Porous PEEK at the State of Spine Surgery.

Video Transcript

Dr. Ryan Roeder: I’m extremely excited to be here.

We’re thankful for the organizers to give us this opportunity at the last minute.

And I get the chance to introduce to you a company you probably haven’t heard of, HAPPE Spine.

And our technology is the world’s first fully porous and bioactive PEEK interbody fusion cage.

Our technology is on our name: HydroxyApatite Porous PEEK.

As we’ve heard at this meeting, it’s an exciting time in spine surgery because there are so many new implant technologies that are available to you.

In addition to the long-established allograft and PEEK.

You know all of these, 3D printed titanium, titanium-coated PEEK, HA-enhanced PEEK, and surface-porous PEEK.

However, all these options that are available to you now can also cause a lot of very difficult decisions, because as we’ve heard, each has its own strengths and weaknesses.

Allograft is obviously bone-like, but can be weak or brittle and difficult to source.

PEEK offers radiolucency, but does not allow for bone on-growth or in-growth.

3D imprinted titanium now enables a design of porous architectures for bone in-growth, but can suffer from brittle fractures in some cases, and difficulty in post-op imaging.

Titanium-coated PEEK and HA-enhanced PEEK promote bone on-growth, but do not allow bone in-growth.

And surface-porous PEEK enables the in-growth at the end plates, but not at the graft space, and still suffers from the fibrous encapsulation that’s endemic to PEEK.

So wouldn’t it be nice if there was one implant technology that could offer all of these advantages that are currently only in the different technologies?

If you agree with me, I think I bring you good news today.

Don’t worry, be HAPPE.

My name is Ryan Roeder, I’m a professor actually, at the University of Notre Dame.

By way of disclosure, I’m board member of HAPPE Spine, and the primary inventor of our technology.

HAPPE Spine has been a spin out from the Genesis Innovation Group.

Our implant technology is wholly owned by HAPPE.

It originated, actually, in my lab more than a decade ago at the University of Notre Dame.

At that time, we were told that our technology was going to be too expensive, too difficult to make, and nobody would want it.

However, recent developments in the market, that you’re all aware of, I believe have set the stage for what we have to offer.

As you know, we did developed HA-enhanced PEEK, which has been shown to mitigate fibrous encapsulation and promote earlier bone on-growth compared with PEEK alone.

Notably in this histology shown by Bill Walsh and his group in Sydney.

Vertera developed surface-porous PEEK, which has been acquired by NuVasive, and has been shown to enable greater in vivo implant fixation compared with PEEK and titanium PEEK, as shown in this study.

We offer both the bioactivity of hydroxyapetite for bone on-growth and porosity for bone in-growth.

Our porosity is not limited to the end plates, but is through the entire implant thickness, and in the graft space where it would most beneficial.

So if you’ll forgive me at this late hour in the morning for using a food analogy, if HA-enhanced PEEK is like peanut butter, and surface-porous PEEK is like chocolate, you know where I’m going, we offer you the peanut butter cup that you’re craving right now, because I’m keeping you from lunch.

So with that, I should describe our technology in more technical detail.

Our current prototypes have a patented dual-density design with dense HA PEEK for load bearing and porous HA PEEK for osteo-integration.

Importantly, our implant design and hydro filler material allows for wicking of blood through the entire implant height, with our obligatory wicking video here.

And afterwards, you can more clearly see the porous and dense architecture in the implant.

Our proprietary manufacturing process allows for seamless integration between the dense and porous materials.

There are no interfaces, there is no bonding.

In other words, there are no places for material failure to occur.

Our process is also adaptable to produce multiple regions of different density, different size in implant design.

Importantly, unlike allograft and some 3D titanium printed cages, our implants will not fracture or fragment upon an extreme overload, as I’m showing here in this video.

In this case, we go into 50% reduction in height without any fracture of the implant.

And the reason for this is because our materials, both the dense and porous materials, have mechanical properties similar to those of bone.

In this graph here, you can see that our porous material has elastic modules comparable to that of the cancellous bone; our dense material has elastic modules comparable to that of the cortical bone.

In contrast, PEEK and porous titanium have a greater stiffness than the cancellous bone.

Of course, the key for bone in-growth is a design porosity.

And as you can see, our porous material looks like the cancellous bone.

It has approximately 75% porosity with spherical pores that are about 200-500 microns in diameter, and they’re greater than 99% connected.

You can see the interconnections at the bottom of those pores in the image.

Thus, our material, we believe is ideal for bone in-growth.

I’m also compelled to note that our spherical core morphology is superior to the cubic core morphology that’s used in surface-porous PEEK.

Here I show measurements of fluid permeability, which is a good indicator of bone in-growth performance.

The spherical origin that we use resulted in an increase in the order of magnitude at the low porosity levels that are 75 and 80%, compared to that of the cubic origin.

For the third and final aspect of our technology, we need to zoom in to the micro and nano scale.

Our implants have bioactive hydroxyapatite whiskers, which are both embedded in the PEEK for mechanical reinforcement and exposed on both machined and interior pore surfaces to provide bioactivity and a microtopography that will promote osteo-integration.

Our hydroxyapatite whiskers provide osteogenic signals to bone forming

(cell phone ringing)

cells by binding proteins–

That’s a customer right there.


So by binding proteins that will provide the osteogenic signals at the surface, at the nano scale.

This is another distinct advantage from existing implants in the market.

A whisker or fiber morphology provides better mechanical properties, and better surface exposure compared to a polymer morphology, which has shown in the high-magnification images on the slide, are more prone to pull out of the surface and then not be present for bioactivity.

So in summary, HA-porous PEEK is the only material able to meet all the desired criteria to make you and your patients happy (HAPPE).

HAPPE Spine offers the radiolucence of PEEK, the designed porosity of 3D porous titanium, the bioactivity of hydroxyapatite, and bone-like mechanical properties.

No other implant in the market can meet all of these criteria.


Thank you.