Background: Sacroiliac joint dysfunctional pain has always been an enigma to the pain physician,
whether it be the diagnosis or the treatment. Diagnostic blocks are the gold standard way to diagnose
this condition. Radiofrequency neurotomy of the nerves supplying the sacroiliac joint has shown equivocal
results due to anatomical variation. Intraarticular depo-steroid injection is a traditional approach to
treating sacroiliac joint pain. For long-term pain relief, however, lesioning the sacral lateral branches may
be a better approach.
Objective: This study compared the efficacy of intraarticular depo-methylprednisolone injection to that
of pulsed radiofrequency ablation for sacroiliac joint pain.
Study Design: This study used a randomized, prospective design.
Setting: Thirty patients with diagnostic block-confirmed sacroiliac joint dysfunctional pain were
randomly assigned to 2 groups. One group received intraarticular methylprednisolone and another group
underwent pulsed radiofrequency of the L4 medial branch, the L5 dorsal rami, and the lateral sacral
branches.
Results: Reduction in Numeric Rating Scale (NRS) for pain at 1 month post-procedure remained similar in
Group A, while in Group B few patients reported a further decrease in the NRS score (3.333 ± 0.4880 and
2.933 ± 0.5936, respectively). At 3 months post-procedure, the NRS score began to rise in most patients in
group A, while in Group B, the NRS score remained the same since the last visit (4.400 ± 0.9856 and 3.067
± 0.8837, respectively). At 6 months post-procedure, the NRS score began to rise further in most patients
in group A. In Group B, the NRS score remained the same in most of the patients since the last visit (5.400
± 1.549 and 3.200 ± 1.207). There was a marked difference between the 2 groups in Oswestry Disability
Index (ODI) scores at 3 months post-procedure (Group A, 12.133 ± 4.486 vs Group B, 9.133 ± 3.523) and
at 6 months post-procedure there was a significant (P = 0.0017) difference in ODI scores between Group A
and Group B (13.067 ± 4.284 and 8.000 ± 3.703, respectively). Global Perceived Effect (GPE) was assessed
in both groups at 3 months post-procedure Only 33.3% (Confidence Interval (CI) of 11.8- 61.6 ) of patients
in Group A had positive GPE responses whereas in Group B, 86.67% (CI of 59.5- 98.3 ) of patients had
positive GPE responses. At 6 months post-procedure, the proportion of patients with positive GPE declined
further in Group A, while in Group B, positive GPE responses remained the same (20% with a CI of 4.30-
48.10 and 86.67% with a CI of 59.5- 98.3, respectively ).
Limitations: Small sample size.
Conclusion: This comparative study shows that pulsed radiofrequency denervation of the L4 and L5
primary dorsal rami and S1-3 lateral branches provide significant pain relief and functional improvement
in patients with sacroiliac joint pain.
Key words: Low back pain, sacroiliac joint dysfunctional pain, radiofrequency, intraarticular injection
The Anatomy of the Lateral Branches of
the Sacral Dorsal Rami: Implications for
Radiofrequency Ablation