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.
Orthopaedic Research Laboratory, Aarhus University Hospital, Aarhus, Denmark. tba@dadlnet.dk
Thomas
T
Andersen
Finn Bjarke
FB
Christensen
Malene
M
Laursen
Lisbet
L
Lund-Olesen
John
J
Gelineck
Cody
C
Bünger
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