In vitro osteoblast proliferation as a predictor for spinal fusion mass.
BACKGROUND
The biological factors determining a successful spinal fusion have not yet been fully determined.


OBJECTIVE
To determine the influence of graft cell vigor on fusion rate and fusion mass using in vitro osteoblast proliferation as a predictor.


METHODS
Animal study randomizing to posterolateral fusion with autograft with or without pedicle-screw instrumentation.


METHODS
Twenty adult Göttingen mini-pigs.


METHODS
Fusion rate measured both with X-ray and computed tomography (CT) as well as amount of fusion mass determined with three-dimensional CT.


METHODS
Animals underwent posterolateral fusion with autograft either with or without pedicle-screw instrumentation. Additional graft was harvested for osteoblastlike cell culture. Cells were counted after 3 weeks, and their proliferative capacity was correlated to fusion rate and fusion amount.


RESULTS
Cell count was significantly higher in the fused animals (p<.011). Furthermore, a tendency toward a positive correlation to fusion mass amount was observed (p<.091).


CONCLUSIONS
The achievement of a solid spinal fusion using autograft is related to properties of the bone-forming cells in the graft and fusion bed. Most likely it is the number of cells and not their proliferative capacity that is the most important factor.
Andersen
Thomas
T
Orthopaedic Research Laboratory, Aarhus University Hospital, Aarhus, Denmark. tba@dadlnet.dk
Christensen
Finn Bjarke
FB
Laursen
Malene
M
Lund-Olesen
Lisbet
L
Gelineck
John
J
Bünger
Cody
C
D000818:Animals; D001863:Bone Screws; D016025:Bone Transplantation; D002452:Cell Count; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D005260:Female; D005544:Forecasting; D007796:Laminectomy / Q000662:veterinary; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D010006:Osteoblasts / Q000166:cytology* / Q000502:physiology; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods / Q000662:veterinary*; D013556:Swine, Miniature; D014057:Tomography, X-Ray Computed / Q000662:veterinary; D014182:Transplantation, Autologous; D016896:Treatment Outcome