• Christopher P Ames, Justin S Smith, Mark C Preul, Neil R Crawford, Grace E Kim, Eric Nottmeier, Robert Chamberlain, Burton Speiser, Volker K H Sonntag, and Curtis A Dickman.
• Comprehensive Spine Center, Department of Neurological Surgery, University of California, San Francisco School of Medicine, San Francisco, CA 94143-0112, USA. amesc@neurosurg.ucsf.edu
• Spine. 2005 Dec 1; 30 (23): 2585-92.

Study DesignAn animal model of posterolateral intertransverse process spine fusion was used.ObjectivesTo investigate whether recombinant human bone morphogenetic protein-2 (rhBMP-2) can overcome the adverse effects of radiation treatment (RT) on spine fusion.Summary Of Background DataSpinal metastases are common. Some of these patients are candidates for spinal cord decompression and vertebral reconstruction; however, radiation has significant adverse effects on bone healing.MethodsA posterolateral fusion model was used with rhBMP-2 or iliac crest bone graft (ICBG). Eighty one-year-old rabbits were divided into eight groups: 1) RT 14 days before surgery, rhBMP-2; 2) RT 14 days before surgery, ICBG; 3) RT 2 days after surgery, rhBMP-2; 4) RT 2 days after surgery, ICBG; 5) RT 14 days after surgery, rhBMP-2; 6) RT 14 days after surgery, ICBG; 7) no RT, rhBMP-2; 8) no RT, ICBG. Animals were killed approximately 35 days after surgery. Manual palpation was the definitive test of fusion. Biomechanical and histologic assessments were also performed.ResultsAll rhBMP-2 groups had significantly greater fusion rates versus respective ICBG control groups: 1 (86%) versus 2 (0%) (P = 0.005), 3 (100%) versus 4 (0%) (P < 0.0001), 5 (100%) versus 6 (0%) (P < 0.0001), and 7 (100%) versus 8 (60%) (P = 0.003). Stiffness and ultimate strength did not differ significantly between the experimental and control groups. Histologic assessment confirmed new bone formation in the fusion masses from rhBMP-2 groups.ConclusionsUse of rhBMP-2 produced a significantly greater rate of fusion compared with ICBG in a previously radiated area in an animal model, without the morbidity of ICBG harvesting and without the risk of inadvertently using autograft contaminated by micrometastases.

20 keywords...

hide…