Abstract
Introduction:
Several reports showed superior fusion rates, as high as 100%, using rhBMP-2 with ALIF cages. This has led to the widespread off-label use of rhBMP-2 in several other lumbar fusion procedures. There is paucity of reports analysing the clinic-radiological outcome of using rhBMP-2 to promote bone union in cases of symptomatic pseudoarthosis following lumbar spine fusion.
Methods:
52 consecutive patients who underwent revision spinal surgery for symptomatic pseudoarthosis utilizing rhBMP-2 between 2008 and 2013 were included in the study. Demographic, and surgical data were collected from medical records. Functional outcomes were recorded using the ODI. All patients had preoperative fine-cut CT scan to confirm pseudoarthosis. Postoperative CT-scan at 6 months was routinely done to confirm fusion.
Results:
Average age at time of revision surgery was 54years (range 28–73). Average follow up was 3 years 5 months (range 2–5 years). Overall fusion rate of 92.3% (48/52) was achieved. The average ODI has improved from 56% preoperatively to 49% postoperatively. We had 1 infection case, and 5 complications related to metalwork. One case with neuronal complications was recorded. No rhBMP-2 related complications. There was no record of heterotopic bone formation in the spinal canal or the neuroforamen.
Conclusion:
Recombinant BMP-2 is a safe and effective adjunct to revision lumbar spinal fusion surgery to alleviate back pain symptoms from pseudoarthosis. The limitations of the study include: retrospective review, lack of matched cohort utilising iliac crest bone graft, and relatively short follow-up.
