Carbon Fiber Reinforced Hybrid Polyaryl–Ether–Ether–Ketone (PEEK) Spinal Fixation System: Technical Features and Preliminary Clinical Trial

To present the clinical result of spinal fixation system made entirely of Carbon-Fiber-Reinforced (CFR)–Hybrid Polyaryl–Ether–Ether–Ketone (PEEK).

Fusion surgery has been used to treat chronic low back pain caused by degenerative disk disease (DDD). The traditional pedicle screw system made of titanium, though biocompatible, can lead to complications, such as stress shielding and implant failure.

Fifty-two patients with one-level degenerative disc disease, with or without spinal stenosis, were treated with a stand-alone novel pedicular screw system (PSS) made entirely of CFR–PEEK composite biomaterial. Forty-six were followed for 24 months. Changes in pain and disability were evaluated using a 0–10-point visual analog scale (VAS) and a 0–90 (after omitting the question related to sex life) Oswestry Disability Index (ODI), respectively. Imaging evaluations of fusion were performed with standard and dynamic radiographs.

Mean age was 58.4 ± 12.7 years. The mean operating time was 114.9 ± 22.7 min; X-ray exposure was 38.5 ± 18.1 s. No operative problems or complications were encountered. Three patients were lost to follow-up and three patients were re-operated. Forty-six patients completed follow-up of 24 months; the mean VAS was 6.49 points for lower back pain and 6.54 for leg pain, and the mean ODI by 41.6. No screw breakage or loosening was reported. Radiological consolidation was observed in all patients within 12 months. No clinical symptoms or radiological signs of adjacent degenerative disc disease were observed up to 24 months.

The all CFR–PEEK PSS is user friendly, safe, and compatible with modern imaging techniques. Its mechanical strength lessens the risk of implant failure, while its bone matching elastic modules seem to contribute in the short term to fusion, and in the long term to potential prevention of adjacent disk disease.