SI-Bone has announced the publication of two-year results from INSITE (Investigation of Sacroiliac Fusion Treatment) a landmark prospective, multicentre, randomised controlled trial of minimally invasive sacroiliac joint fusion with iFuse compared to non-surgical management. Results of this level 1 study have been published in the International Journal of Spine Surgery.
The study showed that rapid improvements in pain, disability and quality of life for the iFuse group were larger than those seen for the non-surgical management group and were durable to two years.
One hundred and forty-eight subjects were enrolled, randomised 2:1 (102 iFuse/46 non-surgical management), and treated at 19 centres in the USA including both private practice and academic institutions. In the iFuse group, the mean sacroiliac joint pain score improved from 82.3 at baseline to 30.1 at six months, 28.6 at 12 months and 26.7 at two years, corresponding to improvements from baseline of 52.3, 53.7 and 55.4 points, respectively (all p<0.0001, Figure 1). Disability, as measured using the Oswestry Disability Index, decreased from a mean 57.2 at baseline to 29.9, 28.3 and 28.7 at months six, 12 and 24, representing mean improvements of 27.4, 28.9 and 28.4 points, respectively (p<0.0001).
The revision surgery rate for iFuse was 3.4% (3/89), and roughly one-third that for lumbar fusion surgery. Two-year results also showed a 29.7% decrease from baseline in the number of study subjects taking opioids (Figure 2) which is consistent with a 28% reduction in opioid use observed in a previously reported prospective multicentre two-year study.