Diagnostic ultrasound-guided lumbar medial branch block of dorsal ramus in facet joint arthropathy: Technical feasibility and validation by fluoroscopy

Abstract

Background: Facet joint (FJ)-mediated pain is one of the frequent causes of low back pain. Fluoroscopy and computed tomography guided medial branch blocks (MBBs) are accepted as standard techniques to diagnose FJ arthropathy. Ultrasound-guided (USG) MBB can be an alternative approach for the diagnostic MBB in FJ arthropathy. This study evaluates the feasibility of USG MBB in FJ arthropathy and validates by fluoroscopy. Materials and Methods: Diagnostic USG MBBs were performed in sixty patients. Two medial branches were targeted for each FJ. The needle was inserted in an in-plane technique after identifying the desired site. The needle position was confirmed by fluoroscopy. Pain scores were assessed before and after the nerve block. Results: Out of 161 needle insertions, 139 needles (86.3%) were at the radiologically defined target point as confirmed by fluoroscopy and were labeled as successful. Mean baseline, immediately before, immediately after, and at 24 h, Numeric Rating Scale (NRS) scores were 7.53 (0.93), 7.02 (0.93), 3.03 (1.75), and 2.80 (1.99), respectively (P < 0.05). The mean Modified Oswestry Disability Questionnaire scores before and 24 h after block were 48.77 (8.94) and 32.55 (11.32), respectively. Fifty-three patients had ≥60 points on the 100-point scale given by Helbig, and out of these patients, 44 patients had a ≥50% reduction in the NRS score. Conclusion: Diagnostic USG lumbar MBBs, a minimally invasive procedure without radiation exposure, can be performed with a high success rate in FJ arthropathy.

Keywords

• back pain
• diagnostic medial branch block
• facet joint arthropathy
• numeric rating scale
• pain
• ultrasound-guided block