Ultrasound-guided pain interventions in the pelvis and the sacral spine

Ultrasound-Guided Coccygeal Nerve Radiofrequency Ablation and Steroid Injection: Combination Therapy for Coccydynia

OBJECTIVES

Coccydynia is characterized by pain in tailbone region, which affects the quality of life. Various interventional procedures are performed for coccydynia that is unresponsive to conservative treatment. This study aimed to evaluate the efficacy of ultrasound (US)-guided radiofrequency ablation (RFA) and steroid injection of the coccygeal nerve in patients with idiopathic and traumatic coccydynia.

METHODS

In this prospective study, 32 patients with coccydynia unresponsive to conservative treatments underwent US-guided RFA of the coccygeal nerve. Coccygeal nerves were visualized at the level of the coccygeal cornua with US, 1 mL lidocaine 2% was injected into both areas and radiofrequency ablation was performed at 90°C for 60 seconds. After RFA, 2 mL dexamethasone and 2 mL bupivacaine 0.5% were injected. Visual Analog Scale (VAS) and Paris scales were used to evaluate the effect of treatment on pain and functionality before and at 1, 4, and 12 weeks after treatment.

RESULTS

We found that 54% of the patients had a >50% reduction in VAS score and 66% of the patients had a >50% reduction in Paris scores measured between baseline and week 12. Additionally, the main effect of time on the VAS and Paris scores was statistically significant (P < .001) in all measurements. Baseline P and VAS scores were higher than the post-treatment measurements (P < .001).

CONCLUSIONS

Our study showed that US-guided steroid injection and RFA of the coccygeal nerve for chronic coccydynia significantly improved pain and function scores at weeks 1, 4, and 12. RFA also results in a lower rate of adverse events. This study is the first clinical trial of ultrasound-guided coccygeal nerve RFA in patients with coccydynia. We believe that this new less invasive method may be an alternative to other interventional treatments.

Ultrasound-Guided Superior Hypogastric Plexus Block: A Cadaveric Feasibility Study with Fluoroscopic Confirmation

Plancarte first described a fluoroscopy-guided superior hypogastric plexus block to manage pelvic pain in 1990. Modifications have since been described using different imaging modalities. Ultrasound-guided approach has been described in a clinical outcome study. However, the accuracy of an ultrasound-guided method has never been validated by alternative imaging. We conducted an experiment aiming to develop ultrasound-guided superior hypogastric plexus block using human cadavers in the supine position. Final needle position and spread of a radiopaque contrast was verified by fluoroscopy, a standard imaging tool. The needle approach to the L5 vertebral body was performed in the short axis as has been recommended. Injection of radiopaque contrast revealed unilateral and cephalad spread to the L5/S1 disk. Additional transabdominal long-axis scanning of the lumbosacral segment was and the needle trajectory was modified to aim for the apex of the L5/S1 disk. Bilateral spread was achieved by strict midline placement of the needle tip and real-time observation of injection. The modified ultrasound-guided technique resulted in a similar spread of injectate as the traditional fluoroscopy-guided technique that in a clinical scenario would offer complete block of the superior hypogastric plexus.