Session VI - Fracture Repair

*Treatment of Tibial Nonunions Using Human Recombinant Osteogenic Protein-1

Clayton R. Perry, MD; J.Dean Cole, MD; George E. Cierny, III, MD; Steven D. Cook, PhD; Samuel Yin, PhD; US Center for Sports Medicine, St. Louis, MO; Orlando Regional Medical Center, Orlando, FL, Tulane University School of Medicine, New Orleans, LA, Stryker Biotech, Natick, MA

Purpose: To test the hypothesis that an osteoinductive bone graft material (NOVOS), comprised of a highly purified Type I collagen matrix and a human osteogenic protein (OP-1), would provide an effective alternative to autogenous bone graft for the treatment of established tibial nonunions.

Method: 122 patients with a total of 124 established nonunions of the tibia were enrolled in a prospective, randomized trial comparing autograft to an osteoinductive bone graft material. All patients underwent open intramedullary nailing of their tibial nonunions and placement of either NOVOS or autograft in an around the nonunion site. The NOVOS device was manufactured by means of recombinant DNA technology. All patients have been followed clinically and radiographically for a minimum of one year.

Results: At 9 month and 12 month follow-up visits, both groups had similar clinical success as measured by the prospectively determined criteria of pain assessment and return to full weightbearing. Risk factors, including duration of nonunion and number of prior surgeries were similar in both the NOVOS and the autograft groups. Treatment parameters, including operative time and duration of hospitalization, were also similar in both groups. Important to note is that the history of tobacco use, which has been linked to the frequency of nonunion, was found to be higher in the NOVOS group (74%) than in the autograft group (59%). There were no serious adverse events associated with the use of NOVOS. And, as anticipated, patients randomized into the autograft group experienced severe, but temporary pain at the autograft harvest site.

Discussion and Conclusion: NOVOS is an effective alternative to autogenous bone graft, the current "gold standard", in the management of nonunion of the tibia. Most importantly, there was no statistically significant difference observed in the clinical incidence of nonunion consolidation between those patients in the NOVOS group and those in the autograft group. This data strongly suggests that NOVOS can be used to effectively treat skeletal defects in humans.