Salvage of Failed Lateral Sacroiliac Joint Fusion with a Novel Posterior Sacroiliac Fusion Device: Diagnostic Approach, Surgical Technique, and Multicenter Case Series.

Background: Studies have found that up to one-third of patients with LBP have sacroiliac joint (SIJ) dysfunction as a contributing cause. Historically, the management of SIJ dysfunction has been plagued by ineffectiveness or significant morbidity. In 2008, minimally invasive lateral SIJ fusion was developed. While this procedure is a safe and effective treatment, there is still a significant proportion of patients who will not experience therapeutic success. There is a paucity of data in the literature regarding the management of these patients. Recently, a novel posterior sacroiliac joint fusion device has been developed which minimizes complications compared to lateral approaches and may serve to salvage therapeutic failures in this patient population. Objective: Determine the efficacy and feasibility of a posterior SIJ fusion device as a salvage technique in patients who have not experienced therapeutic success following lateral SIJ fusion. Design: Multi-center retrospective observational study. Methods: Patients who had previously undergone lateral SIJ fusion and had persistent LBP were evaluated and diagnosed to have persistent primary SIJ pathology. All patients underwent posterior SIJ fusion utilizing a machined allograft transfixing sacroiliac fusion device. Demographic data and patient reported pain scores were collected. Results: A total of 7 patients who had undergone lateral SIJ fusion were included in the study and underwent posterior SIJ fusion. The mean patient reported pain improvement following posterior fusion was 80% with an average follow-up time of 10 months. Median morphine milliequivalents were 20 pre-procedure and 0 post-procedure. Conclusion: We were able to show significant reductions in pain scores and opioid consumption, which suggests that minimally invasive posterior SIJ utilizing a novel implant and technique may be a viable treatment option to salvage pain relief in this patient population. Further, the favorable safety profile of this posterior technique uniquely positions it to be an appropriate first-line surgical therapy.