Session II - Reconstruction

Thurs., 10/20/05 Reconstruction, Paper #5, 3:34 pm

·Treatment of Atrophic Long Bone Nonunions with Human Recombinant Bone Morphogenic Protein-7 (rhBMP-7) in Combination with Autograft or Allograft: Preliminary Results

Anand A. Parekh, MD1 (a-Stryker); Steven J. Morgan, MD1 (a-Stryker);
Wade R. Smith, MD1 (a-Stryker); Christopher T. Born, MD2 (a-Stryker);
Juan F. Agudelo, MD1 (a-Stryker); Allison E. Williams, PhD1 (*);
Roy Sanders, MD3 (*)
1Denver Health Medical Center, Denver, Colorado, USA;
2Temple University, Philadelphia, Pennsylvania, USA;
3Florida Orthopaedic Institute, Tampa, Florida, USA

Purpose: Autologous cancellous bone graft in combination with appropriate bone stabilization is the standard treatment for atrophic long bone nonunions. Autologous bone grafting, however, is associated with donor site morbidity. Our purpose was to determine union and complication rates using rhBMP-7 combined with either autograft or morselized cancellous allograft chips in the treatment of long bone nonunions.

Methods: A prospective IRB-approved protocol, involving 2 level 1 trauma centers, was implemented. Patients received rhBMP-7 combined with either autograft or allograft. The primary outcome measures were presence of postoperative infection, time to achieve clinical and radiographic union, and number of unplanned surgeries following rhBMP-7 implant placement.

Results: 48 patients (30 male, 18 female) were enrolled in the study. The mean age was 50 years (range, 19 to 75). The average number of surgeries prior to rhBMP-7 implant placement was 3 (range, 1 to 13). Twenty patients (42%) had an existing preoperative infection. Of these, 15 (75%) have healed or are showing signs of healing. 79% (n=38) of all atrophic nonunions have healed or are showing signs of progressive bone formation. Of these subjects, 88% and 70% were from the autograft and allograft groups, respectively. 81% (n=17) of tibias, 80% (n=10) of femurs, and 40% (n=10) of humeri have healed or shown signs of progressive bone formation within 9 months after surgery. One patient developed a postoperative infection and required regrafting.

Conclusions/Significance: rhBMP-7 appears effective for the treatment of atrophic nonunions when combined with autograft or allograft. Keeping the limitations of the study in mind, using allograft has a slightly lower success rate than autograft, but no conclusions can be drawn as to the efficacy of autograft versus allograft. Using allograft avoids the complications associated with autograft harvesting. The low success rate in humeral nonunions merits further evaluation. Current study results have led us to initiate a larger multicenter trial to further evaluate safety and efficacy.

· The FDA has not cleared this drug and/or medical device for the use described in this presentation (i.e., the drug or medical device is being discussed for an "off label" use). uFDA information not available at time of printing.
If noted, the author indicates something of value received. The codes are identified as a-research or institutional support; b-miscellaneous funding; c-royalties; d-stock options; e-consultant or employee; n-no conflicts disclosed, and *disclosure not available at time of printing.