Medical Device Daily Associate

Ceramic implants have been popular for knee and hip replacements for some time, and now the material is being used in a spinal implant for the first time in the U.S., and possibly the world, in humans with the recent FDA clearance of a spinal spacer system.

The device is the Arx ceramic spinal spacer system, developed by privately held Amedica (Salt Lake City), as another component of its ceramic technology platform.

According to Cameron Rouns, vice president of sales and marketing, the company was founded in 1996 specifically to look at the orthopedic needs that ceramic composites could bring to patients.

"The company worked very diligently to refine these technology platforms both in super strong articulation applications for hip bearings, knee bearings and spinal disc implants," he told

Medical Device Daily, "and then secondarily, to develop a technology platform that facilitated bony in-growth and adhesion."

The Arx system provides a biocompatible implant based on Amedica's patented MC2 technology that offers physicians and patients an alternative to other synthetic and allograft bone implants used for the restoration of spinal anatomy.

Arx spinal implants are designed as vertebral body replacements for use in the thoraco-lumbar region of the spine to replace collapsed, damaged or unstable vertebral bodies, resulting from such causes as degenerative disease and/or trauma.

Such spinal implants, the company said, are estimated to comprise an annual U.S. market segment of more than $600 million, which Rouns called "a conservative figure."

In articulated joints such as hip and knee implants and even with artificial spinal discs - which the company also is developing and expects to begin clinical work on in the U.S. by mid-2007 - the primary advantage of ceramic materials is their ultra-low-wear properties. For fusion applications in the spine such as the Arx system, the primary advantage of ceramics relates to its excellent diagnostic imaging properties.

Although there are alternative implants in the marketplace, such as those made with titanium and PEEK polymer, as well as grafts taken from human cadavers, each falls short of the combined valuable attributes of Amedica's ceramic spinal spacer system, the company said.

"If you look at what is limiting the synthetic alternatives right now, it's the fact that PEEK [polymer] is radiotransparent so you can't see it," Rouns said. On the other end of the spectrum, he noted that titanium cages "don't have very good imaging qualities for the radiopacity portion [of the device] that you can't see through, or on an MRI you get a halo effect."

The problems with the current gold standard of spinal fusion, allograft bone, are threefold: its availability; its quality and the very real and much-publicized risk of disease transmission.

"The ceramic product offers the superior alternative," Rouns said, "because it's consistent, [and] it has the imaging and the strength properties that are associated with allograft bone but it doesn't have the disease transmission and availability concerns."

Amedica has plans to launch a full platform of spinal stabilization products including cervical plating and a pedicle screw system in the near future, most likely in the first half of 2006.

Currently the company is focusing its attention on the U.S. market, but has plans to enter the European and other CE mark-regulated markets in the latter part of 2007.

As for cash flow, Rouns said Amedica is "very well fixed" at this time, with no venture funding. The company already has gone through two rounds of financing that raised $14 million, with the last one taking place in December 2004. He said the company is in the process of completing a Series C round, which it expects to announce within a month.

The company expects to charge a premium price for the Arx implant, and while he would not disclose an exact price for the device, he noted that a PEEK interbody system that would be used for the same procedure lists for between $4,500 and $5,000.

Amedica has several other products in development using its technology platforms: MC2 ceramic femoral heads for use in hip replacement surgery; Infinia knee implants; Altia spinal disc implants for use in disc replacement surgery; and the CSC platform for its ZeTA spinal fixation implants which substantially mimic natural bone.