An evaluation of the effect of bone morphogenetic protein-2 in a hydroxyapatite carrier on the rate of cortical restoration of large bone defects using the dog ulna model

Abstract

To evaluate the rate of establishment of cortical continuity and union of large bone defects with the use of recombinant bone morphogenetic protein (rh-BMP- 2)/hydroxyapatite implants. Six adult male dogs were used to evaluate the effect of bone morphogenetic proteins (BMP) in filling large cortical defects. A 1.5cm cortical ulnar defect was created in two groups of dogs. First group had 1.5cm BMP implant in a carrier of hydroxyapatite in the cortical defect; the control (group 2) defect was left intact. Evaluation was through serial radiographic determination of mean fracture gaps. There was progressive filling of osseous defects in group 1, which was total at the 16th week post-surgical (PS); group 2 dogs had radiographic non-union at the 16th PS week. It was concluded that BMP implanted with a hydroxyapatite carrier significantly enhanced the rate of cortical restoration of massive bone defects in dogs. Keywords : Bone healing, Bone morphogenetic protein-2, Cortical growth, Dogs, Segmental bone defects, Ulna