A carbon fiber reinforced polymer cage for vertebral body replacement: technical note

We analyzed the surgical technique used for the replacement of damaged vertebral bodies of the thoracolumbar spine and the carbon fiber reinforced polymer (CFRP) cages that are used to replace the pathological vertebral bodies. We also evaluated the biomechanical properties of carbon composite materials used in spinal surgery.

The surgical technique of CFRP implants may be divided into two distinct steps, i.e., assembling the components that will replace the pathological vertebral bodies and connecting the cage to an osteosynthetic system to immobilize the cage.

The CFRP cages, made of Ultrapek polymer and AS-4 pyrolytic carbon fiber (AcroMed, Rotterdam, The Netherlands), are of different sizes and may be placed one on top of the other and fixed together with a titanium rod. These components are hollow to allow fragments of bone to be pressed manually into them and present threaded holes at 15, 30, and 90 degrees on the external surface, permitting the insertion of screws to connect the cage to an anterior or posterior osteosynthetic system.

To date, we have used CFRP cages in 13 patients undergoing corporectomies and 10 patients undergoing spondylectomies. None of our patients have reported complications.

CFRP implants offer several advantages compared with titanium or surgical grade stainless steel implants, demonstrating high versatility and outstanding biological and mechanical properties. Furthermore, CFRP implants are radiolucent and do not hinder radiographic evaluation of bone fusion, allowing for better follow-up studies.