Intra-articular sacroiliac joint steroid injection in patients with risk factors may have greater effect

Low back pain (LBP) is highly prevalent, with the sacroiliac joint (SIJ) implicated in up to ∼30 % of cases. Intra-articular steroid injections are an established treatment for SIJ pain. Several risk factors-including lumbosacral fusion, total hip arthroplasty, pelvic fracture, inflammatory bowel disease, and seronegative spondyloarthropathy-are known to predispose patients to SIJ pain. However, it remains unclear whether these preconditions predict treatment response.

To determine whether the presence of known SIJ pain risk factors correlates with improved patient-reported outcomes following SIJ intra-articular steroid injection.

A retrospective cohort study was conducted at the University of Rochester using electronic medical records from September 1, 2013 to February 1, 2023. Patients aged 18-95 years with SIJ pain who underwent fluoroscopic or ultrasound-guided SIJ injection and completed Patient Reported Outcome Measurement Information System (PROMIS) Pain Interference (PI) and/or Physical Function (PF) surveys before and after injection were included. Outcomes were compared between patients with and without preconditions. Statistical significance was set at p < 0.05. Cohen's d test was preformed to determine the effect of having a precondition.

Of 4780 patients identified, 91 completed PROMIS PI and 168 completed PROMIS PF surveys within the required timeframe. Among these, 27 (PI) and 40 (PF) had a precondition. The mean PI score change was 0.854 in the precondition group and 0.509 in the non-precondition group; PF score change was 1.30 and -0.378, respectively. Neither within-group changes nor between-group differences reached statistical significance (PI p = 0.739; PF p = 0.114). The effect size, measured by Cohen's d, of preconditions versus no preconditions, was d = 0.08 in the PI group, indicating little to no effect. The effect size, measured by Cohen's d, of preconditions versus no preconditions, was d = 0.28 in the PF group, indicating a small effect.

The presence of established SIJ pain risk factors did not predict improved response to intra-articular steroid injection when using t-test for comparison. When using Cohen's d test however, a small effect size of (d = 0.28) was shown for increased PF following SIJ injections in patients with preconditions compared to patients without preconditions. This finding may indicate that patients with the preconditions investigated in this study can be expected to have a marginally better physical function following SIJ injection compared to their peers without preconditions. These findings suggest that preconditions such as fusion, arthroplasty, or inflammatory disease may influence injection efficacy. Larger multicenter studies are warranted to validate these results.