The study evaluated 18 patients for radiographic evidence of fusion at 12 and 24 months following SI joint fusion with decortication and bone grafting. A systematic Computed Tomography (CT) review was predefined and performed by independent radiologists blinded to each other's assessments. Fusion was defined as Solid (presence of solid continuous bridging bone across the treated joint), Possible (presence of possible continuous bridging bone across the treated joint), or No Fusion (no bridging bone). Previously-reported results demonstrated that 79 percent of patients had evidence of bridging bone at 12 months. At 24 months post-op 94 percent of patients had evidence of bridging bone, with 83 percent categorized as Solid fusion across the SI joint. Of patients with Solid fusion, 88 percent of the joints were fused within the area of decortication, demonstrating the importance of this step in achieving fusion.
In addition to fusion, the study demonstrated a 73 percent reduction in average pain at 24 months, maintaining the significant pain relief reported at earlier time points. There were no procedure- or device-related serious adverse events reported.
"Evidence is continually building to support sacroiliac (SI) joint fixation's ability to effectively reduce pain in patients with SI joint disorders," said Dr. William W. Cross III, an orthopedic surgeon specializing in pelvic disorders from Mayo Clinic in Rochester, MN who presented the data at the International Society for the Advancement of Spine Surgery (ISASS) 2017 Annual Meeting. "This study demonstrates the ability of the SImmetry system to achieve pain reduction comparable to other systems, while providing radiographically evident fusion as early as 12 months and increased fusion rates at 24 months. By supplementing fixation with decortication and bone grafting, I can be confident that my patients have the best possible foundation for biological fusion, and long-term relief."
The Centers for Disease Control and Prevention lists back problems as the second most common cause of disability in U.S. adults1. It has been reported that approximately 20 percent of all chronic low back pain derives from the sacroiliac joint2.
1Centers for Disease Control and Prevention. Prevalence of disabilities and associated health conditions among adults—United States, 1999. JAMA. 2001; 285(12):1571-1572.
2Cohen SP et al. Sacroiliac Joint Pain: A Comprehensive Review of Epidemiology, Diagnosis and Treatment. Expert Rev Neurother. 2013; 13(1):99-116