Sacroiliac Joint Fusion Intervention For Mobility, Pain Relief, and Lasting Improvement in Functional Recovery "SIMPLIFY"

1. Age ≥ 21 at time of screening;
2. Diagnosis of unilateral sacroiliac (SI) joint dysfunction (degenerative sacroiliitis or sacroiliac disruption)
3. Presence of low back/buttock pain and unresponsive to non-operative treatment for at least 6 months or has the presence of progressive symptoms in the face of conservative treatment; Oswestry Disability Index (ODI) score ≥ 30%;
4. SIJ pain score ≥ 5 on 0-10 numerical rating scale (NRS);
5. Ability and willingness to comply with follow-up regimen; and
6. Written informed consent by the patient

Exclusion Criteria:

1. Low back/buttock pain due to other causes including, but not limited to, lumbar disc degeneration, lumbar disc herniation, lumbar spondylolisthesis, lumbar spinal stenosis, lumbar facet degermation, or lumbar vertebral body fracture;
2. Planned bilateral SI joint fixation
3. Received prior SI joint fusion1;
4. Cluneal neuralgia;
5. Inflammatory sacroiliitis (e.g., ankylosing spondylitis, psoriatic arthritis, reactive arthritis, non-radiographical axial spondyloarthritis, inflammatory bowel disease-associated arthritis);
6. Sacroiliac tumor as source of symptoms;
7. Sacroiliac fracture or unresolved trauma as source of symptoms;
8. Anatomic anomalies/defects that in the opinion of the Investigator preclude device placement
9. History of recent (\<1 year) major trauma to pelvis;
10. History of suspected history of severe osteoporosis (defined with a prior T-score \< -2.5 or history of osteoporotic fracture);
11. Autoimmune disorders that impact the musculoskeletal system (e.g., lupus, rheumatoid arthritis);
12. History of fibromyalgia;
13. Infection at the site of surgery;
14. Known or suspected allergies to titanium or titanium alloys
15. Pregnant (verified in patients of childbearing potential by a negative urine pregnancy test when preadmission testing is obtained), or interested in becoming pregnant during the duration of the study;
16. A body mass index (BMI) > 35;
17. Currently pursuing personal litigation (defined as litigation that will likely influence the patient's ability or willingness to accurately report their treatment outcomes) related to the sacroiliac;
18. Currently receiving worker's compensation related to the sacroiliac;
19. Current or recent history of substance abuse (drug or alcohol) per the Investigator's determination;
20. Mental conditions (e.g., schizophrenia, personality disorders) that could interfere with study participation, per the investigator's determination;
21. Use of any investigational drug or medical device within the last 60 days prior to surgery;
22. Tobacco and/or nicotine use within the last 60 days prior to surgery, or tobacco and/or nicotine use during the duration of the study;
23. Currently a prisoner; 1Prior allograft implant is acceptable and not exclusionary