The use of recombinant human bone morphogenetic protein-2 for the treatment of a delayed union following femoral neck open-wedge osteotomy

Although the clinical potential of bone morphogenetic proteins (BMPs) has been known for decades, their use in humans has only been approved for a limited number of orthopaedic conditions. Promising results in animals demonstrate the utility of BMP-2 in regional bone repair without using osteoconductors. To our knowledge, no comparable human case has been described. We report the case of a 50- year-old who suffered a femoral neck fracture. After 9 months of extensive treatment, he was still not pain-free. The following open-wedge osteotomy resulted in a therapy-resistant delayed union. We therefore conducted 4 computer tomography-guided injections of recombinant human (rh) BMP-2 into the bone gap. No osteoconductor was employed. Six weeks later, there was a 55-60% defect filling. Followup examination showed a complete union of the bone defect. Our case report shows that in a complicated delayed union rhBMP-2 can be successfully used to induce bone formation without any osteoconductor.