Resorbable cages for spinal fusion: an experimental goat model.
OBJECTIVE
A biomechanical cadaveric study and an in vivo monosegmental spinal fusion study were performed to evaluate a novel bioresorbable poly(L-lactic acid) (PLLA) cage.


METHODS
The yield strength of a spinal segment was chosen as the main design parameter for the resorbable cages to be used in a goat model. In a 3-year in vivo study the authors found fusion to be significantly faster and more complete when using PLLA cages compared to titanium cages with the same dimensions. In the PLLA group, the intervertebral grafting height did not change and bone remodeling within the cage was completed 2 years after implantation. In terms of degradation of the PLLA, similar features were observed in vivo and in vitro.


CONCLUSIONS
Degradation was almost completed 3 years after implantation. Tissue reaction was mild during the 3-year period.
Wuisman
P I J M
PI
Department of Orthopedic Surgery, Vrije Universiteit Medical Center, Amsterdam, The Netherlands.
van Dijk
M
M
Smit
T H
TH
D020341:Absorbable Implants; D000818:Animals; D001672:Biocompatible Materials / Q000627:therapeutic use*; D001696:Biomechanical Phenomena; D015194:Diffusion Chambers, Culture / Q000295:instrumentation; D004195:Disease Models, Animal; D006041:Goats; D008159:Lumbar Vertebrae / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D011091:Polyesters / Q000627:therapeutic use*; D020127:Recovery of Function / Q000502:physiology; D013123:Spinal Fusion / Q000295:instrumentation*; D013124:Spinal Injuries / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D013997:Time Factors
D001672:Biocompatible Materials; D011091:Polyesters; C033616:poly(lactide)