Center Valley, PA (January 28, 2019) – Aesculap Implant Systems, LLC today announced the publication of "Porous titanium-coated polyetheretherketone implants exhibit an improved bone–implant interface: an in vitro and in vivo biochemical, biomechanical, and histological study" in Medical Devices: Evidence and Research.¹ The paper combined in vitro and in vivo analysis to examine the Plasmapore^XP technology (Aesculap AG, Tuttlingen, Germany), a porous titanium surface enhancement that has been shown to create an ideal osteoconductive environment for bone formation during spinal fusion. 

This recently published data reinforces decades of clinical experience with the Plasmapore technology, starting with the surface-enhanced BiContact hip implant over 30 years ago. In addition to this study, clinical outcomes have been reported on over 1,000 spine and orthopedic patients treated with an Aesculap surface-enhanced implant; however, this is the first published study that provides a direct histological comparison between the Plasmapore^XP surface and uncoated polyetheretherketone (PEEK). Additionally, this is the first peer-reviewed publication to document the presence of nanofeatures created by Aesculap’s proprietary titanium plasma spray manufacturing process.

The primary goal of the paper was to characterize how osteoblast-like cells interact and respond to the Plasmapore^XP surface when compared to uncoated PEEK. The authors found that early bone-forming activity was upregulated in osteoblast-like cells that attached to the Plasmapore^XP surface. In an in vivo sheep model, this translated into an increase in early bone formation, apposition and pullout strength at 12 and 24 weeks. 

Analysis using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) demonstrated that the proprietary titanium plasma spray manufacturing process creates reproducible microporosity and nanotopography on the implant surface. 

“Although the benefits of surface porosity in bone formation have been widely accepted, the spine healthcare community is just beginning to understand that nanofeatures may also have a role to play in how best to optimize these surfaces at the bone-implant interface,” said author Boyle Cheng, PhD (Allegheny Health Network Neuroscience Institute, Pittsburgh, PA). “Until now, there has been some confusion about whether the titanium plasma spray manufacturing process can actually create reproducible nanofeatures. This is the first peer-reviewed publication to confirm that this specific proprietary process does in fact produce unique surface features that are tens of nanometers in size. This should be no surprise, as the Plasmapore process has been well characterized over the past decades in large joint orthopedic implant applications. We continue to find ways to bring technologies to the spine field in hopes of improving better patient outcomes through science.”

The authors believe that the nanofeatures, in combination with the microporosity and natural biocompatibility of titanium, help contribute to the significant increase in bone cell differentiation on the Plasmapore^XP surface. In in vitro cultures, cells demonstrated significantly higher levels of ALP and BMP-2, early bone cell differentiation markers, when compared to levels observed on uncoated PEEK.

With the goal of continuing to broaden the 30-year compendium of evidence surrounding the Plasmapore^XP technology, Aesculap has sponsored Open Access to this publication, which can found on the Dove Press website. 

"Evidence like this helps explain the high fusion rates I’ve seen in my day-to-day practice," said surgeon Jeffrey Kozak, MD (Texas Orthopedic Hospital, Houston, TX). “When the Arcadius^®XP L lumbar stand-alone implant launched in 2012, Aesculap was the first company with a surface-enhanced spinal implant. This publication isn’t surprising, as they’ve always had the same commitment to developing evidence-based technology.”

In 2018, Aesculap expanded the Plasmapore^XP portfolio through the US launch of Arcadius^XP C, a stand-alone anterior cervical interbody. To date, there have been over 50,000 Plasmapore^XP surface-enhanced interbody devices implanted worldwide. 

_{¹ Cheng BC, Koduri S, Wing CA, Woolery N, Cook DJ, Spiro RC. Porous titanium-coated polyetheretherketone implants exhibit an improved bone–implant interface: an in vitro and in vivo biochemical, biomechanical, and histological study. Medical Devices: Evidence and Research. 2018; Volume 11:391-402.}