Triangular Titanium Implants for Minimally Invasive Sacroiliac Joint Fusion: 2-Year Follow-Up from a Prospective Multicenter Trial

Duhon B, et al. Int J Spine Surg. 2016;10:Article 13.

Abstract

Background

Sacroiliac joint (SIJ) dysfunction is an underdiagnosed condition. Several published cohorts have reported favorable mid-term outcomes after SIJ fusion using titanium implants placed across the SIJ. Herein we report long-term (24-month) results from a prospective multicenter clinical trial.

Methods

One hundred and seventy-two subjects at 26 US sites with SI joint dysfunction were enrolled and underwent minimally invasive SI joint fusion with triangular titanium implants. Subjects underwent structured assessments preoperatively and at 1, 3, 6, 12, 18 and 24 months postoperatively, including SIJ pain ratings (0-100 visual analog scale), Oswestry Disability Index (ODI), Short Form-36 (SF-36), EuroQOL-5D (EQ-5D), and patient satisfaction. Adverse events were collected throughout follow-up. All participating patients underwent a high-resolution pelvic CT scan at 1 year.

Results

Mean subject age was 50.9 years and 69.8% were women. SIJ pain was present for an average of 5.1 years prior to surgical treatment. SIJ pain decreased from 79.8 at baseline to 30.4 at 12 months and remained low at 26.0 at 24 months (p<.0001 for change from baseline). ODI decreased from 55.2 at baseline to 31.5 at 12 months and remained low at 30.9 at 24 months (p<.0001 for change from baseline). Quality of life (SF-36 and EQ-5D) improvements seen at 12 months were sustained at 24 months. The proportion of subjects taking opioids for SIJ or low back pain decreased from 76.2% at baseline to 55.0% at 24 months (p <.0001). To date, 8 subjects (4.7%) have undergone one or more revision SIJ surgeries. 7 device-related adverse events occurred. CT scan at one year showed a high rate (97%) of bone adherence to at least 2 implants on both the iliac and sacral sides with modest rates of bone growth across the SIJ.

  

Conclusions

In this study of patients with SIJ dysfunction, minimally invasive SI joint fusion using triangular titanium implants showed marked improvements in pain, disability and quality of life at 2 years. Imaging showed that bone apposition to implants was common but radiographic evidence of intraarticular fusion within the joint may take more than 1 year in many patients.

This prospective multicenter clinical trial was approved by local or regional IRBs at each center prior to first patient enrollment. Informed consent with IRB-approved study-specific consent forms was obtained from all patients prior to participation

Author Information

Bradley S. Duhon, MD,1 Fabien Bitan, MD,2 Harry Lockstadt, MD,3 Don Kovalsky, MD,4 Daniel Cher, MD,5 Travis Hillen, MD,6 on behalf of the SIFI Study Group.

1 University of Colorado Dept. of Neurosurgery, Aurora, CO,
2 Manhattan Orthopedic Spine, New York, NY,
3 Bluegrass Orthopaedics & Hand Care, Lexington,KY,
4 Orthopaedic Center of Southern Illinois, Mt Vernon, IL,
5 SI-BONE, Inc. San Jose, CA,
6 Washington University School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, MO

Disclosures

One or more of the individuals named herein may be a past or present SI-BONE employee, paid consultant, investor, clinical trial investigator, or grant recipient. Research described herein was supported by SI-BONE.

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