Simplify Disc 2-Level Cervical Disc Replacement Prospective Outcome Data from FDA IDE Trial Presented at NASS 2020


162. 2-level Cervical Disc Replacement Using a PEEK-on-Ceramic Device: Prospective Outcome Data from an FDA IDE Trial

Domagoj Coric, MD1; Richard D. Guyer, MD2; Pierce D. Nunley, MD3; K. Brandon Strenge, MD4; Donna D. Ohnmeiss, PhD5

1Carolina Neurosurgery & Spine Associates, Charlotte, NC, US; 2Center for Disc Replacement at Texas Back Institute, Plano, TX, US; 3Spine Institute of Louisiana, Shreveport, LA, US; 4The Orthopaedic Institute of Western Kentucky, Paducah, KY, US; 5Texas Back Institute, Plano, TX, US

Presented at the North American Spine Society (NASS), October 9, 2020


While there have been several large-scale FDA Investigational Device Exemption (IDE) studies on single-level cervical total disc replacement (TDR) such information is available for only 2 devices used for 2-level disc replacement. One of these devices has metallic endplates and a plastic core, the other is a 2-piece device machined from a titanium-ceramic composite. A TDR designed with titanium-coated PEEK endplates and a biconvex zirconia toughened alumina ceramic core is being evaluated in an IDE trial for 2-level implantation.


The purpose of this study was to investigate preliminary outcomes of the PEEK-on-ceramic TDR based on 3 sites participating in the 2-level trial.

Study design/setting

This was a prospective study based on data from 3 of 18 centers participating in the TDR arm of a prospective study evaluating two-level cervical TDR using a non-concurrent historical control.


These preliminary outcomes were based on 62 patients at 12 months post-operative following 2-level cervical TDR.

Outcome measures

Patient reported outcome measures included the Neck Disability Index (NDI) and numerical rating scores (NRS) separately assessing neck and arm pain intensity. Radiographic measures made at the index levels included disc height and flexion/extension range of motion (ROM).


Patients enrolled in the trial received the Simplify® PEEK-on-ceramic TDR. Evaluations were conducted prior to surgery and at 6 weeks, and 3, 6, and 12 months after surgery. All radiographs were analyzed by an independent lab specializing in image assessment.


The mean NDI score decreased significantly (p<0.01) from 55.6 prior to surgery to 12.7 at 12-month follow-up. Neck pain decreased significantly from 7.9 to 2.3 by 6-week follow-up and 1.7 at 12-month follow-up. Pre-operatively, mean right and left arm pain scores were more than 5.0, and decreased significantly (p<0.01) to values of less than 1.5 at all follow-up visits. Radiographically, the mean disc heights at both implanted levels increased significantly (p<0.01) at all follow-up points compared to the pre-operative values. The mean height of the superior TDR level increased from 3.2 mm pre-op to 4.3 mm at 12 months post-operative. The mean height of the inferior level was 2.9 mm prior to surgery and 3.8 mm at 12 months after surgery. The ROM of the inferior level implanted increased significantly from 6.1o to 8.7 o at 12-month follow-up. At the superior implanted level, the mean ROM increased, but not significantly from 8.4o prior to surgery to 9.4o at 12 months after surgery.


Preliminary results of this IDE study found that 2-level cervical TDR using the PEEK-on-ceramic implant was associated with significant decreases in pain and function scores, which were maintained during 12-month follow-up. Disc height of the operated segments were increased after surgery and remained increased through 12-month follow-up. ROM was increased, significantly at the superior level and non-significantly at the inferior level. These early results suggest that the device may be a future consideration for the treatment of symptoms arising from 2-level degenerative conditions of the cervical spine. Patients from all centers continue to be followed annually.

FDA Device/Drug Status: Simplify disc (Investigational/Not approved)


See the Difference Today