Ultrasound-guided radiofrequency Ablation for SI joint pain:An observational study.

OBJECTIVE

An ultrasound (US) guided RFA technique for the SIJ, utilizing bipolar RF cannula placements along the lateral sacral crest (LSC), has been proposed in anatomical studies. This study evaluated changes in pain intensity, function and quality of life following this technique.

METHODS

Patients achieving ≥50% pain relief on two blocks (one FL- and one US-guided) were included. US-guided SIJ RFA was performed with sequential bipolar lesions using two multitined RF cannulae placed along the LSC. The Pain, Disability, Quality of Life Questionnaire-Spine (PDQQ-S), which includes an 11-point (0-10) numeric rating scale (NRS) for pain intensity, was completed pre-RFA, and 2, 6, 9, 12 and 16 months post-RFA. Outcomes at 2 months post-RFA were compared between US-guided and FL-guided SIJ RFA in participants with previous FL-guided SIJ RFA.

RESULTS

31 patients were included. Statistically significant decreases in pain intensity were observed up to 9 months after US-guided SIJ RFA (Baseline NRS: mean ​= ​6.8 SD ​= ​1.6, 95%CI [6.169, 7.347]; 9 month: mean ​= ​4.8, SD ​= ​2.6, 95%CI [3.891, 5.786]; p ​= ​0.0005), and up to 12 months for PDQQ-S. A clinically significant ≥2 point reduction in pain intensity on the NRS was seen in 48.4% of participants at 9 months. 11 participants had previous FL-guided SIJ RFA; no statistically significant differences were found in pain intensity or PDQQ-S scores between US- and FL-guided SIJ RFA 2-months post-RFA.

CONCLUSIONS

Preliminary results suggest that SIJ RFA could be performed using US guidance. Further study is required to establish effectiveness.