A consideration for the utility of the post-operative Oswestry Disability Index for measuring outcomes after sacroiliac joint fusion

Effect of revision sacroiliac joint fusion on unresolved pain and disability: a retrospective cohort study

PURPOSE

The sacroiliac (SI) joint is recognized as a source of low back pain in 15-30% of patients. Though randomized controlled trials have shown clinical improvement following SI joint fusion in 83.1% of patients, revision rates of 2.9% within 2 years have been reported. There is a paucity of literature reviewing this small yet significant population of patients requiring revision surgery.

METHODS

Following IRB approval, retrospective review of patients, who underwent a revision SI joint fusion from 2009 to 2021 was completed. Patient-reported outcomes were measured before and at each clinic visit after surgery with visual analoge scale (VAS) for back pain and Oswestry Disability Index (ODI). Patient characteristics (chronic opiate use and prior lumbar fusion) and surgical factors (operative approach, type/number of implants and use of bone graft) were recorded. Patient-reported outcomes were evaluated with Paired t and Wilcoxon signed rank tests. Univariate and multivariate logistic regression determined if patients met the minimally clinical important differences (MCID) for VAS-back pain and ODI scores at 1 year.

RESULTS

Fifty-two patients (77% female) with an average age of 49.1 (SD ± 11.1) years met inclusion criteria. Forty-four had single sided revisions and eight bilateral revisions. At 1 year follow-up there was no significant improvement in VAS-Back (p = 0.06) or ODI (p = 0.06). Patients with chronic opioid use were 8.5 times less likely to achieve the MDC for ODI scores (OR 0.118, p = 0.029). There was no difference in outcomes when comparing the different surgical approaches (p = 0.41).

CONCLUSION

Our study demonstrates patients undergoing revision surgery have moderate improvement in low back pain, however, few have complete resolution of their symptoms. Specific patient factors, such as chronic opiate use and female sex may decrease the expected improvement in patient-reported outcomes following surgery. Failure to obtain relief may be due to incorrect indications, lack of biologic fusion and/or presence of co-pathologies. Further clinical examination and consistent long-term follow-up, clarify the role revision surgery plays in long-term patient outcomes.

Minimally invasive sacroiliac joint fusion for chronic sacroiliac joint pain: a systematic review

BACKGROUND CONTEXT

Sacroiliac (SI) joint pain causes significant disability and impairment to quality of life (QOL). Minimally invasive SI joint fusion is increasingly used to relieve chronic SI joint pain among patients who do not respond to nonsurgical treatment.

PURPOSE

To systematically review the existing literature to assess the effectiveness and safety of minimally invasive SI joint fusion.

STUDY DESIGN/SETTING

Systematic review.

DATA SOURCES

PubMed, Embase, Cochrane, and a clinical trial registry from database inception to June 30, 2021.

STUDY SELECTION

Eligible studies were primary research studies published in the English language, enrolled adults with SI joint pain, and compared SI joint fusion to nonsurgical interventions or alternative minimally invasive procedures. We included randomized controlled trials (RCTs) or controlled cohort studies (CCSs) that reported effectiveness (pain, physical function, QOL, opioid use) or safety outcomes (adverse events [AEs], revision surgeries) and uncontrolled studies that reported safety outcomes.

DATA ABSTRACTION AND SYNTHESIS

Data were abstracted into structured forms; two independent reviewers assessed risk of bias using standard instruments; certainty of evidence was rated using GRADE.

RESULTS

Forty studies (2 RCTs, 3 CCSs, and 35 uncontrolled studies) were included. Minimally invasive SI joint fusion with the iFuse Implant System appeared to result in larger improvements in pain (two RCTs: mean difference in visual analog scale -40.5 mm, 95% CI, -50.1 to -30.9; -38.1 mm, p<.0001) and larger improvements in physical function (mean difference in Oswestry Disability Index -25.4 points, 95% CI, -32.5 to -18.3; -19.8 points, p<.0001) compared to conservative management at 6 months. Improvements in pain and physical function for the RCTs appeared durable at 1- and 2-year follow-up. Findings were similar in one CCS. The two RCTs also found significant improvements in QOL at 6 months and 1 year. Opioid use may be improved at 6 months and 1 to 2 years. AEs appeared higher in the fusion group at 6 months. The incidence of revision surgery varied by study; the highest was 3.8% at 2 years. Two CCSs compared the effectiveness of alternative minimally invasive fusion procedures. One CCS compared iFuse to the Rialto SI Fusion System and reported no differences in pain, function, QOL, and revision surgeries from 6 months to 1 year. One CCS compared iFuse to percutaneous screw fixation and reported significantly fewer revisions among iFuse participants (mean difference -61.0%, 95% CI, -78.4% to -43.5%). The 35 uncontrolled studies had serious limitations and reported heterogeneous safety outcomes. Two of the larger studies reported a 13.2% incidence of complications from minimally invasive SI joint fusion at 90 days using an insurance claims database and a 3.1% incidence of revision surgery over 2.5 years using a postmarket surveillance database.

CONCLUSIONS

Among patients meeting diagnostic criteria for SI joint pain and who have not responded to conservative care, minimally invasive SI joint fusion is probably more effective than conservative management for reducing pain and opioid use and improving physical function and QOL. Fusion with iFuse and Rialto appear to have similar effectiveness. AEs appear to be higher for minimally invasive SI joint fusion than conservative management through 6 months. Based on evidence from uncontrolled studies, serious AEs from minimally invasive SI joint fusion may be higher in usual practice compared to what is reported in trials. The incidence of revision surgery is likely no higher than 3.8% at 2 years. Limited evidence is available that compares different minimally invasive devices.

International Society for the Advancement of Spine Surgery Policy 2020 Update-Minimally Invasive Surgical Sacroiliac Joint Fusion (for Chronic Sacroiliac Joint Pain): Coverage Indications, Limitations, and Medical Necessity

The index 2014 International Society for the Advancement of Spine Surgery Policy Statement-Minimally Invasive Surgical Sacroiliac Joint Fusion-was generated out of necessity to provide an International Classification of Diseases, Ninth Revision (ICD-9)-based background and emphasize tools to ensure correct diagnosis. A timely ICD-10-based 2016 update provided a granular threshold selection with improved level of evidence and a more robust and relevant database (Appendix Table A1). As procedures and treatment options have evolved, this 2020 update reviews and analyzes the expanding evidence base and provides guidance relating to differences between the lateral and dorsal surgical procedures for minimally invasive surgical sacroiliac joint fusion.