RT Journal
A1 Smoljanović, Tomislav
A1 Bojanić, Ivan
A1 Pećina, Marko
T1 The Use of Bone Morphogenetic Protein in Lumbar Spine Surgery
JF The Journal of Bone & Joint Surgery
JO The Journal of Bone & Joint Surgery
YR 2009
FD August 1
VO 91
IS 8
SP 2045
OP 2046
DO 
UL http://dx.doi.org/
AB 
As we pointed out in a previous letter to the Editor1, the dose of rhBMP-2 used per level of lumbar interbody fusion was decreased by 30% between two studies2,3 cited by Rihn et al., even though the publications represented two sequential phases of a level-I study conducted under strict control by the Food and Drug Administration. We disagree with Rihn et al. that no transient vertebral osteolysis was associated with the use of rhBMP-2 in the first phase3, as vertebral resorption that was not reported in that phase was identified on computed tomography scans made six months after rhBMP-2 application4 (Fig. 104). An analysis, by our group5, of reported cases of transient vertebral resorption revealed that patients in whom the resorption developed after application of rhBMP-2 in lumbar interbody fusion were often susceptible to spacer subsidence, loss of correction, graft migration, and failure of the spinal interbody fusion even with additional stabilization of fused levels. What is of interest is how such large amounts of resorption4 were not associated with any spacer subsidence or loss of correction, especially as no additional instrumentation was used2,3. The authors of two papers reported a prevalence of resorption after lumbar interbody fusion supplemented with rhBMP-2 that was substantially higher than the 7%6 and 18%2,7 mentioned by Rihn et al. In addition, McClellan et al.8 and Vaidya et al.9 reported a prevalence of 69%, and most recently Vaidya et al.10 reported a prevalence of 82%.