Predictors of Success With the iFuse Implant System Confirmed in Pooled Analysis

New findings confirm that the minimally invasive SI joint fusion with the iFuse Implant™ (iFuse) significantly improves pain, patient function, and quality of life in patients with sacroiliac (SI) joint dysfunction, and that the extent of improvement is associated with smoking status, opioid use, patient age and duration of pain. The findings are based on a patient-level pooled analysis of data from three prospective multicenter clinical trials published online ahead of print in Spine.

The findings are based on a patient-level pooled analysis of data from three prospective multicenter clinical trials.Data From Three Multicenter Prospective Trials Evaluated
The pooled analysis included 423 patients from the three multicenter prospective trials: two randomized controlled trials and one single-arm trial. Across these studies, 326 patients received SI joint fusion with the iFuse Implant System and 97 patients received non-surgical management (NSM) between 2013 and 2015.

The SI joint fusion group showed a 37.9-point greater adjusted reduction in SI joint pain (P<0.0001), 18.3-point greater improvement in Oswestry Disability Index (P<0.001), and 0.24-point greater improvement in EuroQoL-5D compared to the NSM group (P<0.0001).

Predictors of Outcome With iFuse System Found
In the NSM group, no predictors of improved outcomes were found. In contrast, in the iFuse group, smoking and opioid use were predictive of smaller improvements in pain relief and disability (Table). In addition, patients aged >59 years or with longer pain duration had greater improvements in pain compared with younger patients or patients with shorter pain duration. The findings were statistically significant and showed moderate clinical significance. Even subgroups with smaller improvements after SI joint fusion (eg, smokers and opioid users) showed clinically significant improvements after SI joint fusion compared with the NSM group.

Table: predictors of pain relief with SI Joint FusionEfficacy Data Was Consistent Across Studies
“When you conduct multiple clinical studies in the USA and Europe, the hope is that the findings will be consistent regardless of where the treatments are performed,” said Jeffrey Dunn, President and Chief Executive Officer of SI-BONE. These three trials were conducted at 54 study centers in total, of which 9 were in 4 countries in Europe. Thus, we believe the findings confirm the durability and consistency of the efficacy findings, Mr. Dunn told SpineUniverse.

Mr. Dunn explained that this pooled analysis marks the publication of the 50^th peer-reviewed study of the iFuse implant system.

The iFuse Implant System is comprised of patented, triangular titanium implants coated with a porous, titanium plasma spray designed to help decrease implant motion and have greater than 30 times the rotational resistance of a screw, Mr. Dunn said. The implants, inserted laterally, also allow for biological fixation to support long-term fusion, according to the implant manufacturer SI-BONE. The minimally invasive surgical option is intended for SI fusion for conditions, including SI joint dysfunction resulting from SI joint disruption and degenerative sacroiliitis.

“The Spine pooled analysis, along with a previously published 5-year study and an accepted 6-year study all support fusion and pain reduction durability,” explained Mr. Dunn.