Thornton Cleveleys, United Kingdom – Polymeric spinal rods provide a bridge between rigid all-metal spinal implants and more dynamic therapeutic options. Adopting this “bridging” approach, France-based Innov’spine, a leading specialist in innovative solutions for spinal surgery, is offering a new PEEK-polymer rod system in its VEOS product line. The new rods are made of PEEK-OPTIMA, an implantable polyetherether-ketone (PEEK) polymer available from Invibio Biomaterial Solutions. A notable feature is the use of polyaxial screws – previously, systems were only available with monoaxial screws. These new rods, which originate as a semi-finished product from Invibio, have gained CE mark approval for their use in Europe, a further signal that PEEK-polymer spinal implants are now widely recognized, within the medical profession, as the therapeutic option of choice.
“PEEK-polymer solutions for interbody spinal fusion are now the medical-technology leaders. The exceptionally versatile PEEK-OPTIMA has a modulus close to that of human bone, and this allows it to be a natural bridge between very rigid metal implants, such as the titanium constructs, and more dynamic approaches,” commented Dr. Thierry Desjardins, neurosurgeon (Cagnes-sur-Mer, France). In fact, PEEK-polymer implants offer numerous benefits, including radiolucency, which of course metals don’t allow, while retaining the stability of titanium.”
Spinal rods composed of metal have been used successfully for many years. They are, however, not a perfect solution. Breakage and loosened screws can occur and result in accelerated degeneration at adjacent spinal segments. The high stiffness inherent in all-metal implants is believed to contribute to these clinical challenges and their subsequent negative impact on patient outcomes.1, 2 In response, surgeons have indicated that enhanced flexibility, within a range of rod stiffness, would be beneficial for patients.2
In addition, health systems would also benefit from this innovative and cost-effective solution, which is able to assist in reducing the number of patients with Adjacent Segment Diseases (ASD). According to a study, the treatment of patients with ASD following lumbar fusion results in significantly higher costs. These costs are related to hospital admission, surgery, imaging, and total direct costs, and add up overall to nearly US$17,000.3
Polyaxial screws
Importantly, the new PEEK-OPTMA polymer-rod system from Innov’spine supports the use of a polyaxial-type screw. Previously only monoaxial screws had been available for spinal-rod implants, but polyaxial screws enable better alignment of the screw head with the rod, helping to avoid pre-stressing and damage to the rod. Biomechanical testing has in fact demonstrated that the thermoplastic spinal-rod components maintain better screw purchase,4 reduce screw movement and avoid potential screw pull-out and implant failure.4, 5
The new spinal-rod components offer a compelling combination of strength and flexibility that significantly reduces the range of motion2, 6 and stabilizes the treated segment,7 while allowing adequate physiological movement in adjacent upper and lower segments.6 In addition, clinical results increasingly suggest that PEEK-OPTIMA spinal-rod components can preserve adjacent discs or at least slow their degeneration.8
“Increasingly spinal surgeons are adopting polymer implants made of Invibio´s novel PEEK-OPTIMA polymer. The European CE mark granted to our new rod system with polyaxial screws is also a clear indicator that the new solution bridges existing treatment gaps,” said Fabrice Paccagnella, founder – general manager at Innov’spine. “Use of polymer spinal implants decreases stress at the extremely critical interface of bone and screw. This effectively protects adjacent levels and offers an alternative solution that lies between a completely rigid system, on the one hand, and a too-dynamic system on the other. This approach optimizes long-term stability and the prognosis for a positive therapeutic outcome.”
