SI-BONE, Inc. Announces Publication of 5 year Follow-up data for iFuse Implant System®

Results support long-term durability of positive clinical outcomes including pain relief, improvement in function and satisfaction with surgery

San Jose, California, October 27, 2014 -- SI-BONE, Inc., a medical device company that pioneered the use of the iFuse Implant System, a minimally invasive surgical (MIS) device indicated for fusion for certain disorders of the sacroiliac (SI) joint, today announced favorable 5 year clinical and radiographic outcomes for the iFuse procedure.  Clinical improvements observed at 12 months were maintained or improved at 5 years including low back pain relief, function and patient satisfaction for patients treated with iFuse. This report entitled “Five-Year Clinical and Radiographic Outcomes after Minimally Invasive Sacroiliac Joint Fusion using Triangular Implants1” was published in the The Open Orthopaedics Journal.  This is the first publication reporting long-term results for MIS SI joint fusion using the iFuse Implant System. 

Results support the long-term durability of positive clinical outcomes of patients treated for degenerative sacroiliitis and/or SI joint disruptions with MIS SI joint fusion using a series of triangular TPS coated implants.  These findings are consistent with multiple clinical case series previously published and a recently published multi-center prospective study.

Twenty-one consecutive patients participated in this single-center study. Of these, 17 provided clinical information and 15 patients underwent x-ray and CT imaging at 5 years.  Clinical improvements observed at 12 months postoperatively were maintained or improved at the 5-year time point, including patient satisfaction (82% at both).  Level of pain, assessed using a 0-10 (0 = no pain, 10 = worst pain imaginable) visual analog scale (VAS), improved from 8.3 at baseline to 3.4 at 12 months and further improved to 2.4 at 5 years. Functional improvement was assessed based on an SI joint survey instrument that evaluated the ability to perform light, moderate and vigorous activities as well as sleep disturbance, overall happiness and effect of pain on social life.  The ability to perform light, moderate and vigorous activities showed continual improvement from 12 months to the 5 year time interval.  Mean Oswestry Disability Index (ODI) score, a measure of disability due to back pain measured at 5 years only, was 21.5, indicating minimal to moderate disability.2

There were no intraoperative or long-term complications reported and there was no evidence of device migration.  Qualitative review of x-ray and CT imaging, obtained at both 1 and 5 years following surgery, showed increased bone density immediately adjacent to all implants, suggestive of biological fixation, and no evidence of implant loosening or migration. “Evidence of osseous bridging across the SI joint was clearly seen on 13 of 15 (87%) of patients.”  The percentage of patients who achieved substantial clinical benefit (SCB), defined as a 2.5 point decrease in VAS pain score or a follow-up score of less than 3.5, remained high at each time point (77% at 12 months, 82% at 24 months and 88% at 60 months).

Dr. Gunnar Andersson, President of the International Society for the Advancement of Spine Surgery (ISASS) commented: “There are well over a dozen peer-reviewed publications now that demonstrate safety and effectiveness of the iFuse Implant System.  This most recent publication reporting 5 year results provides further clinical evidence that this minimally invasive surgical technique is safe and effective and provides lasting relief for patients who suffer from certain SI joint disorders.”

SI-BONE, Inc. received original 510(k) clearance in November 2008 from the Food and Drug Administration (FDA) to market its iFuse Implant System. The CE mark for European commercialization was obtained in November 2010.

Clinical publications have identified the SI joint as a pain generator in up to  30% of low back pain patients.3,4,5,6  In addition, the prevalence of SI joint pain in post-lumbar fusion, so called “failed back surgery” patients, has been shown to be 43%.7  Initial treatment options for patients with SI joint disorders typically involve non-surgical management and, when non-surgical treatment of the SI joint fails, surgical treatments such as the iFuse procedure may provide an option.

The iFuse Implant System is a minimally invasive surgical option that uses titanium implants coated with a porous, titanium plasma spray (TPS) that acts as an interference surface, designed to help decrease implant motion, provide immediate fixation and allow for biological fixation to support long term fusion.  The iFuse System is intended for sacroiliac joint fusion for conditions including SI joint dysfunction that is a direct result of SI joint disruptions and degenerative sacroiliitis.  As with all surgical procedures and permanent implants, there are risks and considerations associated with surgery and use of the iFuse Implant.  Physicians should refer to the product labeling for a discussion of these risks and patients should talk with their doctors about these risks before deciding if the iFuse Implant is right for them.


About SI-BONE, Inc.

SI-BONE, Inc. (San Jose, California) is the leading sacroiliac joint medical device company dedicated to the development of tools and products for diagnosing and treating patients with low back issues related to SI joint disorders.  The company has developed, and is manufacturing and marketing, less invasive approaches using implants for the treatment of certain SI joint pathology.  SI-BONE has an experienced management team with extensive experience in orthopedic and spine medical devices.  SI-BONE and iFuse Implant System are registered trademarks of SI-BONE, Inc. ©2014 SI-BONE, Inc. All Rights Reserved. 8946.102714

Rudolf L,a Capobianco R.b  Five-Year Clinical and Radiographic Outcomes after Minimally Invasive Sacroiliiac Joint Fusion using Triangular Implants.  The Open Orthopaedics Journal.  2014;8: 375-383.
Fairbank JC, Pynsent PB. The Oswestry Disability Index. Spine. 2000 Nov 15;25(22):2940–2952; discussion 2952.
3 Bernard TN, Kirkaldy-Willis WH. Recognizing Specific Characteristics of Nonspecific Low Back Pain. Clinical Orthopedics and Related Research. 1987;217:266–80.
4 Schwarzer AC, Aprill CN, Bogduk N. The Sacroiliac Joint in Chronic Low Back Pain. Spine. 1995;20:31–7.
5 Maigne JY, Aivaliklis A, Pfefer F. Results of Sacroiliac Joint Double Block and Value of Sacroiliac Pain Provocation Tests in 54 Patients with Low Back Pain. Spine. 1996;21:1889–92.
6 Sembrano JN, Polly DW.c How Often is Low Back Pain Not Coming From The Back? Spine. 2009;34:E27–32.
7 DePalma M, Ketchum JM, Saullo TR. Etiology of Chronic Low Back Pain Patients Having Undergone Lumbar Fusion. Pain Medicine. 2011;12:732-9.


a Paid consultant of and has an ownership interest in and conducts clinical research for, SI-BONE, Inc.
b Employee of SI-BONE Inc.
c Investigator on a clinical research study sponsored by SI-BONE.  No financial interest in SI-BONE.