Minimally Invasive Lateral Transfixing SI Joint Fusion: Six-Month Results from the Prospective, Multicenter STACI Study

Sunday, March 30, 2025

3:45 PM – 3:54 PM CT

Location: Music City Center, 207 AB

Presenting Author(s)

Douglas Beall, MD, FSIR

Chief of Radiology Services
Comprehensive Specialty Care, United States

Author/Co-author(s)

Dan TD Nguyen, MD

Medical Director
Neuroradiology & Pain Solutions of Oklahoma, United States
JW

Jacqueline Weisbein, DO

Interventional Pain Management Specialist
Napa Valley Orthopaedics, United States
JS

Jack Smith, MD

Interventional Pain Management Specialist
Neurosurgical Associates of Lancaster, United States
DP

Denis Patterson, DO

Interventional Pain Management Specialist
Nevada Advanced Pain, United States
TD

Timothy Davis, MD

Interventional Pain Management Specialist
Source Healthcare, United States
AC

Anne Christopher, MD

Interventional Pain Management Specialist
St.Louis Pain Consultants, United States
DK

Daniel Kloster, MD

Interventional Pain Management Specialist
Crimson Pain Management, United States
AT

Andrew Trobridge, MD

Interventional Pain Management Specialist
Comprehensive Pain and Spine Care, United States
JH

John Hatheway, MD

Interventional Pain Management Specialist
Northwest Pain Care, United States
Ch

Caroline harstroem, MD

Interventional Pain Management Specialist
Anesis Spine and Pain Care, United States
JB

John Broadnax, MD

Interventional Pain Management Specialist
Advanced Pain Institute of Texas, United States
EA

Eric Anderson, MD

Interventional Pain Management Specialist
Advanced Pain Institute of Texas, United States
JF

Jeffrey Foster, DO

Interventional Pain Management Specialist
Ascentist Healthcare, United States
CS

Charles Simmons, MD

Interventional Pain Management Specialist
Clearway Pain Solutions, United States
MH

Michael Harned, MD

Medical Director of UK Healthcare’s Interventional Pain Medicine
University of Kentucky, United States
CM

Christopher J. Mallard, MD

Assistant Professor of Anesthesiology
University of Kentucky, United States

Purpose: The purpose of this study is to evaluate the safety and efficacy of lateral transiliac sacroiliac joint fusion (SIJF) using threaded implants when performed by interventional pain management (IPM) physicians.

Materials and Methods:

STACI (NCT 05870488) is a prospective, multicenter study that will evaluate the safety and efficacy of lateral SIJF when performed by IPM physicians. 110 enrolled participants across 15 sites will be followed at regular intervals for 2 years. The primary endpoint is SIJ pain change from baseline at 6 months; secondary endpoints include improvements in pain, function, and quality of life at all time points, and CT evidence of fusion at 2 years.

Adults with a confirmed diagnosis of SIJ disorders using NASS criteria, refractory to non-operative care were screened for eligibility. Eligibility criteria include: SIJ pain score ≥ 5/10, ODI score ≥ 30%, excluded are those with prior SIJF, severe non-SIJ back pain, interfering comorbidities, and worker’s compensation. Follow-up visits are conducted at 1-, 3-, 6-, 12-, and 24-months post-surgery. Baseline and procedural characteristics, patient reported outcomes at 3- and 6-month follow-up, and adverse events are reported.

Results:

To date, 106 participants are enrolled and undergone SIJ fusion, 65 have completed 3-months of follow-up, and 41 have completed 6-months of follow-up. Mean (SD, range) age is 63.7 (14.0, 25-89), BMI is 29.3 (5.1), and 68% are female. Mean (SD) operative time was 45.1 (16.1) minutes, EBL was minimal, and 100% of procedures were performed outpatient.

At 3-months, mean (SD) SIJ pain decreased from 7.6 (1.5) at baseline to 2.6 (2.5, p < 0.001), and mean (SD) ODI decreased from 52.1 (13.5) at baseline to 28.8 (16.9; p < 0.001). At 6-months, participants showed sustained relief, with mean SIJ pain and mean ODI measuring 2.2 (2.1; p < 0.001) and 28.2 (16.2; p < 0.001), respectively.

Conclusion:

The interim results of this prospective trial support the safety and sustained efficacy of lateral SI joint fusion using a threaded implant when performed by IPM physicians. Full primary endpoint results are expected in early 2025.