161. Cervical disc replacement using a PEEK-on-ceramic implant: prospective data from seven sites participating in an FDA IDE trial for single-level surgery

Abstract

BACKGROUND CONTEXT The first cervical total disc replacements (TDRs) used on a large-scale basis, produced motion through a ball-and-socket action, with metal endplates articulating with a plastic core. Various designs followed: metal-on-metal devices, a titanium-ceramic composite device, as well as a compressible disc with metal endplates. The use of PEEK material for spinal implants continues to increase, primarily due to its mechanical and positive imaging properties (ie, no metallic artifact on MRI or CT). A TDR was designed with titanium-coated PEEK endplates and a biconvex zirconia toughened alumina ceramic core. PURPOSE The purpose of this study was to evaluate preliminary results of seven sites participating in the single-level Investigational Device Exemption (IDE) study for a PEEK-on-ceramic TDR. STUDY DESIGN/SETTING This is a prospective study evaluating the cervical TDR using a non-concurrent historical control. Data from 7 of 16 sites participating in the investigational arm are provided. PATIENT SAMPLE The device was implanted into 123 patients at 7 of 16 sites participating in the FDA IDE trial for single-level cervical degenerative radiculopathy with or without spinal cord compression from C3 to C7. Twelve-month data were available for 120 patients and 24-month data were available for 87 patients. OUTCOME MEASURES Outcome measures included the Neck Disability Index (NDI), visual analog scale (VAS) assessing neck and arm pain, and the Dysphagia Handicap Index (DHI). Radiographic assessment of the operated level included disc height, flexion/extension range of motion, and lordosis. METHODS Patients enrolled in the trial received the Simplify PEEK-on-ceramic TDR. Evaluations were conducted prior to surgery and within 2 weeks, 6 weeks, and 3, 6, 12 and 24 months after surgery. Radiographs were analyzed by an independent lab specializing in image assessment. RESULTS Mean NDI scores decreased significantly (p CONCLUSIONS Preliminary results of this study found the PEEK-on-ceramic disc replacement produced significant decreases in pain and function scores, which were maintained through the 12- and 24-month follow-up. Range of motion, disc height, and lordosis of the operated segment were significantly increased after surgery and maintained during follow-up. The values were similar to those reported in other FDA IDE trials for cervical TDR. FDA DEVICE/DRUG STATUS Simplify (Investigational/Not approved)