A new study published in Spine compares spinal fusion with rhBMP-2 and without rhBMP2.
The researchers examined the Medline clinical studies database for studies published between 2000 and 2012 comparing fusion rates after anterior lumbar interbody fusion, posterior lumbar interbody/transforaminal lumbar interbody fusion and posterolateral lumbar fusion with and without rhBMP-2. There were 16 studies reviewed and 1,794 patients included in the study.
There were 995 patients treated with rhBMP-2 and 799 without. The researchers found:
1. There were no significant improvements in fusion rates when rhBMP-2 was used compared with those that didn't have rhBMP-2 at the longest follow up in these studies:
• Five of five studies for PLIF/TLIF — 301 patients
• One of four studies for ALIF — 279 of 589 patients
• Three of seven studies for PLF — 272 of 904 patients
2. The average fusion rate at 24 months after surgery with rhBMP-2 was:
• ALIF: 97.8 percent
• PLIF/TLIF: 95.7 percent
• PLF: 93.6 percent
3. The average fusion rate without rhBMP-2 was:
• ALIF: 88.2 percent
• PLIF/TLIF: 89.5 percent
• PLF: 83.1 percent
4. The odds ratio of fusion for ALIF was calculated at 7.08; for PLIF/TLIF it was 1.9; and for PLF it was 3.06 with rhBMP-2 as compared with without rhBMP-2.
5. The study authors conclude that although many studies didn't show significant improvement with rhBMP-2, combining the studies showed significant fusion rate improvement with rhBMP-2 for ALIF and PLF.
"Notably, even when pooling data from several studies, rhBMP-2 did not result in statistically significantly improved fusion rates in PLIF/TLIF. However, heterogeneity of rhBMP-2 dosing, surgical techniques and quality of papers reviewed may limit the validity of conclusions drawn," the authors reported.