Augmentation of spinal fusion with bone morphogenetic protein in XXXX .

@entity1 @entity235 @entity7049 @entity158 @entity6861
Bone morphogenetic protein ( @entity6861 ) induces mesenchymal cells to differentiate into cartilage and bone. To investigate the action of @entity6861 on the growth of host bed-derived bone in experimental spinal fusions, posterior intervertebral spinal fusions of the lower thoracic spine were performed in 13 mature mongrel @entity235 . Four different fusion methods were used at single intervertebral levels within each @entity235 . Three levels in each @entity235 were used as controls for the @entity6861 level. The spinal columns were examined by radiohistomorphometric methods at three weeks, six weeks, and 12 weeks and showed the @entity6861 level to have two to three times more new bone than control levels. At the @entity6861 level, an increase in the amount of new bone was observed in the interval from three to 12 weeks, in contrast to a decrease seen at the control levels. Fusion was present in five of seven of the @entity6861 levels compared with zero of seven, one of seven, and two of seven in the control levels. The @entity6861 level exhibited an increased number and volume of areas of de novo cartilage and woven bone formation at all time intervals compared to all control levels. The @entity7049 polymer carrier was not resorbed and partially retained in the fusion site. The preliminary observations suggest that @entity6861 may serve as a useful adjunct in spinal fusions, but research is required to find a rapidly degradable delivery system. The objective of @entity6861 research is to augment the host bed capacity for bone generation and regeneration and to spare @entity1 and adults the @entity158 and complications involved in removing excessive volumes of iliac crest bone grafts.
