19 February 2018 – Medical Plastics News
A wealth of research and clinical experience is confirming that the use of PEEK-Optima polymer-based spinal implants confers advantages that can, potentially, enhance the efficacy of spinal implants and improve patient outcomes. Combined data from three clinical studies that directly compared PEEK-Optima with titanium devices for cervical fusion showed fusion rates between 88-100% for PEEK-Optima versus 47-93% for titanium devices.1-3 The high-performing polymer was the first implantable PEEK and introduced by Invibio Biomaterial Solutions (Invibio) in 1999. Since that time the company has pioneered further innovations and supported its partner companies with pre-clinical study results and clinical outcome data to achieve regulatory clearances and to help educate the medical community.
One such recent PEEK-based innovation was Invibio´s PEEK-Optima HA Enhanced polymer. It combines PEEK-Optima polymer with hydroxyapatite (HA) for medical applications where bone on-growth is required. Hydroxyapatite, a well-known osteoconductive material that enhances bone apposition and a constituent of human bone, is fully integrated, not coated, into the PEEK matrix, making it available on all surfaces of a finished device, which also eliminates the time and expense of applying coatings to the manufactured implant. 
Invibio´s enhanced biomaterial offers all the clinical advantages of PEEK-Optima Natural, including a modulus close to that of human bone, reduced stress shielding, and artifact-free imaging, whether by X-ray, MRI or CT scanning, allowing clear visual assessment of the fusion mass.
Pre-clinical studies demonstrate the potential benefits of PEEK-Optima HA Enhanced
The performance of PEEK-Optima HA Enhanced has been studied in pre-clinical studies, and has demonstrated a greater amount of new bone formation and a higher quality of new bone bridging, within early stages of treatment, compared with the results obtained when using PEEK-Optima Natural.
Invibio commissioned an independent cervical fusion study in sheep, to compare outcomes between interbody fusion devices composed of PEEK- Optima HA Enhanced, PEEK- Optima Natural and allograft bone. Results indicate that PEEK- Optima HA Enhanced may provide several advantages4:
- Greater new bone formation. PEEK- Optima HA Enhanced resulted in greater new bone formation at six weeks, compared with PEEK- Optima Natural.
- Higher quality new bone bridging. PEEK- Optima HA Enhanced provided a more favorable environment, with higher quality local bone at six and 12 weeks compared with PEEK-OPTIMA Natural.
- Enhanced mechanical performance. PEEK- Optima HA Enhanced devices outperformed allograft, with fracture of the allograft devices in 6/13 (46%) instances.
A previous study had evaluated and compared the bone ongrowth that resulted from the use of the two implantable polymers in a bone defect model in sheep, and revealed that PEEK- Optima HA Enhanced resulted in approximately 75% direct bone apposition as early as four weeks following implantation compared with PEEK- Optima Natural.5