Interbody lumbar fusion using a carbon fiber cage implant versus allograft bone. An investigational study in the Spanish goat.
METHODS
A carbon fiber-reinforced polymer implant, designed to aid interbody lumbar fusion, was tested biologically in an experimental surgical model. Twenty-seven Spanish goats had interbody lumbar fusion surgery in a randomized protocol. Seventeen goats were implanted with the carbon fiber-reinforced polymer cage packed with autologous bone, and 10 goats were implanted with ethylene oxide-sterilized allograft bone.


OBJECTIVE
To determine fusion success, biocompatibility of the carbon polymer material, and possibility of carbon wear debris at intervals after surgical implantation.


METHODS
Goats were killed at 6 months, 12 months, and 24 months and full-body autopsies were done. Spine specimens were studied by plain radiography, three-dimensional reformatted computed tomography studies, and histology.


RESULTS
At 6 months, one of three allograft implantations showed histologic and radiographic fusion, whereas five of five carbon fiber-reinforced polymer cage fusions showed at least partial fusion. At 12 months, two of three allograft implantations and five of five carbon fiber-reinforced polymer cage fusions were solidly fused. At 24 months, five of five allograft implantations and three of three carbon fiber-reinforced polymer cage implantations were solidly fused.


CONCLUSIONS
Interbody fusion using a carbon cage implant packed with autologous bone achieved a quicker and more reliable fusion compared with ethylene oxide-sterilized allograft bone. There were no adverse effects from the implant material.
Brantigan
J W
JW
Department of Surgery, Creighton University, Omaha, Nebraska.
McAfee
P C
PC
Cunningham
B W
BW
Wang
H
H
Orbegoso
C M
CM
D000818:Animals; D001672:Biocompatible Materials; D016025:Bone Transplantation; D002244:Carbon; D000077482:Carbon Fiber; D004867:Equipment Design; D006041:Goats; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D011108:Polymers; D019736:Prostheses and Implants; D011859:Radiography; D013123:Spinal Fusion / Q000295:instrumentation* / Q000379:methods; D013997:Time Factors; D014182:Transplantation, Autologous; D014184:Transplantation, Homologous
D001672:Biocompatible Materials; D000077482:Carbon Fiber; D011108:Polymers; D002244:Carbon