THE EFFECT OF FIBRIN SEALANT ON SPINAL FUSIONS USING ALLOGRAFT IN DOGS

Study Design. This study investigated the use of tisseel (Immuno [Cana da], Toronto, Ontario) as an adjunct to allograft spinal fusion. Thirt een mongrel dogs were fused bilaterally with morcellized graft from a separate dog. Objectives. To evaluate whether fibrin sealant had an ef fect on bone volume of fusion mass in allograft fusions of the spine. Summary of Background Data. Fibrin sealant has been promoted fro use i n many orthopedic applications. There is controversy about its effecti veness in augmenting bone graft healing. However, some surgeons make r outine use of the sealant in augmentation of bone grafting procedures. Methods. To test the usefulness of this material in augmenting allogr aft fusions, the authors carried out bilateral posterolateral fusions in 13 mongrel dogs. At surgery, 15 cm(3) of allograft was placed into a posterolateral position at the L5-L6 region on both sides of the spi ne. Fibrin sealant (Tisseel) was allocated randomly to one side only. Fusion mass was tested 6 months after the initial operation by compute d tomographic scan imaging and mechanical testing. Results. A signific antly smaller bone volume mass, as illustrated by computed tomographic measurement, was seen on the Tisseel side (P = 0.03). Biomechanical t esting indicated that there was a trend for the Tisseel side to be sti ffer than the untreated side, particularly at lower weights, but stati stical significance was not achieved. Computed tomographic volumetric analysis showed that tisseel-treated allograft led to a significantly smaller fusion volume. Conclusions. This study refutes the belief that Tisseel is a good material for accomplishing or augmenting interverte bral arthrodesis. Fibrin sealant significantly retards allograft fusio n mass formation in dogs.