Impaction bone-grafting increases the holding power of cancellous screws in the femoral head : A pull-out study in human cadaver hips

Abstract

We studied the effect of impaction of fresh cancellous bone or demineralized bone matrix (DBM) around cancellous screws in 25 cadaver femoral heads. The bone mineral content (BMC) of femoral heads was measured to determine if greater relative increase in holding power will be achieved by impac-tion-grafting, as the BMC of the specimen decreases. A 60% (p < 0.001) relative increase in the pull-out force was achieved by impaction-grafting with DBM, compared to non-grafted controls. The augmenting effect of fresh cancellous bone graft and DBM did not differ significantly. The relative improvement in holding power was not inversely correlated to femoral head BMC, but was inversely related to the pull-out resistance of non-grafted control screws. These findings suggest that impaction-grafting provides significantly better hold of cancellous screws in femoral heads.