OBJECTIVE: Sacroiliac joint (SIJ) dysfunction is a significant cause of back pain. Despite recent advances in minimally invasive (MIS) SIJ fusion, the fusion rate remains controversial. This study sought to demonstrate that a navigated decortication and direct arthrodesis technique in MIS SIJ fusion would result in satisfactory fusion rates and patient-reported outcomes (PROs). METHODS: The authors retrospectively reviewed consecutive patients who underwent MIS SIJ fusion from 2018 to 2021. SIJ fusion was performed using cylindrical threaded implants and SIJ decortication employing the O-arm surgical imaging system and StealthStation. The primary outcome was fusion, evaluated using CT at 6, 9, and 12 months postoperatively. Secondary outcomes included revision surgery, time to revision surgery, visual analog scale (VAS) score for back pain, and the Oswestry Disability Index (ODI), measured preoperatively and 6 and 12 months postoperatively. Patient demographics and perioperative data were also collected. PROs over time were analyzed using ANOVA followed by a post hoc analysis. RESULTS: One hundred eighteen patients were included in this study. The mean (± SD) patient age was 58.56 ± 13.12 years, and most patients were female (68.6% vs 31.4% male). There were 19 smokers (16.1%) with an average BMI of 29.92 ± 6.73. One hundred twelve patients (94.9%) underwent successful fusion on CT. The ODI improved significantly from baseline to 6 months (Δ7.73, 95% CI 2.43–13.03, p = 0.002) and from baseline to 12 months (Δ7.54, 95% CI 1.65–13.43, p = 0.008). Similarly, VAS back pain scores improved significantly from baseline to 6 months (Δ2.31, 95% CI 1.07–3.56, p < 0.001) and from baseline to 12 months (Δ1.63, 95% CI 0.25–3.00, p = 0.015). CONCLUSIONS: MIS SIJ fusion with navigated decortication and direct arthrodesis was associated with a high fusion rate and significant improvement in disability and pain scores. Further prospective studies examining this technique are warranted.

A 39-year-old male presented with a two-month history of right hip pain. Computed tomography (CT) scan demonstrated right sacroiliac joint space widening with cortical destruction and erosive changes in the iliopsoas muscle. Minimally invasive right sacroiliac joint fusion was performed with biopsy and aspirate, which confirmed positive Brucella cultures. The patient was started on long-term antibiotic therapy, and his pain significantly improved. Pyogenic sacroiliitis is a rare condition that requires a high index of suspicion. In this case, minimally invasive sacroiliac joint fusion successfully treated the patient’s pain and instability as well as aided in the diagnosis of Brucella infection.

Introduction Sacroiliac joint (SIJ) dysfunction has been shown to cause significant morbidity. Current treatment includes conservative management and surgical intervention. Previously published data reporting clinical and surgical outcomes reached conflicting conclusions. This protocol aims to conduct a meta-analysis to determine fusion rates and patient-reported outcomes of minimally invasive (MIS) SIJ fusions compared with conservative treatment. Methods and analysis We drafted our protocol according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. We will search PubMed, Embase and the Cochrane Library, supplemented by manual search when necessary. Two independent reviewers will screen for eligibility by title/abstract, then full text, arbitrated by a third reviewer if necessary. The two reviewers will carry out a risk of bias assessment using the Cochrane Collaboration Risk of Bias tool for randomised controlled trial and the Methodological Index for Non-Randomised Studies tool for observational cohort studies. A third reviewer will arbitrate any disagreement. We will perform data synthesis using Review Manager (RevMan for Windows, V.5.4.1, The Cochrane Collaboration, 2020) and Comprehensive Meta-Analysis (V.3.3.070). Meta-bias will be evaluated and confidence determined using the Grading of Recommendations, Assessment, Development and Evaluation guidelines. Ethics and dissemination Ethical approval for this review will not be required as no patient data is being collected. The results of this study will be submitted for publication in peer-reviewed journals. PROSPERO registration number CRD42021273481.

Purpose: Sacroiliac joint (SIJ) dysfunction is a frequently overlooked source of persistent low back pain after lower lumbar surgery. The SIJ is an adjacent joint to the lower lumbar spine and can thus be subject to adjacent segment disease (ASD) after lower lumbar fusion. Spinopelvic imbalance can potentially predispose a patient to ASD in the SIJ, causing SIJ dysfunction. However, the impact of spinopelvic imbalance following minimally invasive (MIS) lower lumbar fusion on SIJ dysfunction and, thus, subsequent fusion remains inconclusive. We sought to determine whether spinopelvic imbalance after lower lumbar fusion predisposes patients to subsequent MIS SIJ fusion (SIJF). Methods: We retrospectively reviewed consecutive elective lower lumbar fusion patients (ending levels L5/S1) to select our cases and controls in a 1:1 match. We included patients who underwent MIS lower lumbar fusion from 10/2005 to 05/2021 at a single institution with an ending level including L5 or S1, a starting level at or below T12, and had at least two years of follow-up. We excluded patients with inadequate or absent postoperative X-rays, those who underwent lumbar fusion for trauma or infection, pelvic fixation, revision lumbar surgery, and prior SIJF. We performed a pilot study to determine the sample size as 190 per group. Confounders, including the number of pregnancies, were collected. Consistent with prior literature, we defined spinopelvic imbalance as a PI-LL mismatch of <-10° or > 10° [1–5]. We compared the groups using univariate analysis. The odds of developing SIJF related to PI-LL mismatch were calculated using Chi-Square. We performed multivariable analysis modeling on SIJF to adjust for covariates. Results: We included 488 patients (203 SIJF vs. 285 control). Between groups, the SIJF patients were significantly younger (52.55 ± 12.81 vs. 55.84 ± 14.71; P = 0.005), had a higher proportion of females (67.5% vs. 55.1%; P = 0.006), and increased levels fused (1.78 ± 0.97 vs. 1.38 ± 0.64; P < 0.001). Interestingly, number of pregnancies was not significantly different (P = 0.791). PI-LL mismatch demonstrated a 3.54 increased odds of requiring subsequent SIJF (p < 0.001). Multiple logistic regression adjusting for age at lumbar fusion, female sex, and number of levels demonstrated that PI-LL mismatch (OR 1.10; 95% CI 1.06–1.15; p < 0.001) and operative levels (OR 1.84; 95% CI 1.42–2.39; p < 0.001) were independently associated with significantly increased odds of requiring SIJF, while age (OR 0.98; 95% CI 0.96–0.99; p < 0.001) and female sex (OR 0.54; 95% CI 0.36–0.81; p = 0.003) were associated with significantly decreased odds of requiring SIJF. Conclusion: PI-LL mismatch following MIS lower lumbar fusion was independently associated with significant odds of requiring subsequent SIJF. Optimizing spinopelvic imbalance can decrease the odds of requiring subsequent SIJF after MIS lower lumbar surgery. Given the biases associated with the retrospective and observational nature of our study design, further prospective studies are needed.