study group for Chronic Pain (TriPal Trial)

The sacro-iliac joint is a large joint that can be the source of chronic pain. Many treatment options have been proposed to treat SIJ pain, with variable efficacy. The next step in managing those patients who can't get sustained pain relief from conservative treatment is radiofrequency ablation (RFA) of the SIJ's posterior innervation. However, the success rate of SIJ RFA, as determined by the proportion of patients reporting greater than 50% pain relief 6 months after the intervention, varies substantially across studies, ranging from 38-71 %. This may be explained partly by the fact that there may be incomplete lesioning of the target nerves supplying the joint. To overcome these particularities, two RFA techniques have emerged: cooled RFA and bipolar RFA. Cooled radiofrequency is the one that has been studied the most, and good evidence supports its efficacy. However, its superiority to conventional RF for the treatment of SIJ pain is not confirmed. Alternatively, a bipolar RFA technique using conventional radiofrequency needles and equipment can be used. The efficacy of this relatively newer technique has been demonstrated by only one study, and although the results were promising, it is not known whether they could be replicated. The success of the palisade technique could be enhanced by using multi-tined expandable electrodes, such as the 3-tined Trident cannulas, with only small increases in cost. In clinical practice, the palisade technique using 3-tines needles is routinely used. However, its efficacy has not been formally evaluated. The primary objective of this prospective cohort study will be to determine the success rate of the palisade SIJ RFA (P-RF) technique using the 3-tined needles, determined as the proportion of patients reporting \>50% pain relief, 6 months after the procedure.