Posterior allograft sacroiliac joint fusion with pre-operative mapping.

Background: Low back pain is a highly prevalent and disabling condition. Sacroiliac joint dysfunction is prevalent in up to 62 % of some populations and is a common origin of low back pain. The posterior approach for minimally invasive sacroiliac joint fusion with an allograft is still relatively novel, with limited studies examining its safety and efficacy. Objective: The objective of our study was to analyze changes in pain and opioid usage for patients who underwent this procedure with pre-operative mapping after exhausting conservative treatment methods. Methods: This was a single-center, retrospective study with all cases completed by a single interventional pain physician. Outcomes regarding pain and opioid usage were extracted from electronic medical records, Georgia Prescription Drug Monitoring Program reports, and all other available state databases for 208 consecutive patients who underwent the minimally invasive sacroiliac joint fusion procedure with the LinQ Fusion Implant (PainTeq, Tampa, FL) after pre-operative mapping between August 2019 and October 2022. Pain was assessed using the Numerical Rating Scale (NRS), and opioid consumption was measured using Morphine Milligram Equivalents (MME). Results: NRS scores decreased from 7.23 ± 1.82 at baseline to 1.16 ± 1.35 at the final available follow-up (p < 0.001). Pain improvements ranged from 40 to 100 %, and all patients reported at least some improvement post-intervention. 205 of the 208 patients reported an improvement in pain of at least 50 %. MME reduced from 20.74 ± 26.33 mg to 10.00 ± 18.69 mg (p < 0.001). Conclusion: Posterior allograft sacroiliac joint fusion significantly reduces pain and opioid consumption. Pre-operative mapping is beneficial but requires more evidence to elucidate its role in optimizing implant placement.