Randomized controlled trial comparing technical features and clinical efficacy of a multi-tined cannula versus a conventional cannula for cervical medial branch radiofrequency neurotomy in chronic neck pain.

Objectives: Compare procedural characteristics and clinical efficacy of cervical medial branch radiofrequency neurotomy (CMBRFN) using a multi-tined cannula (MTC) versus a conventional cannula (CC) to treat chronic neck pain.

Design: Prospective, double-blinded randomized controlled trial.

Methods: Patients who responded to dual medial branch blocks with ≥75% pain relief were randomized to receive RFN with either the MTC or the CC. Primary outcomes: procedural pain, procedure duration, fluoroscopy time and radiation dose. Secondary outcomes: proportion of patients reporting ≥50% numerical rating scale reduction and ≥30% neck disability index reduction at 3, 6 and 12 months.

Results: Forty-two patients underwent treatment. There was no difference in procedural pain between the MTC and CC groups (NRS 4.7 ± 2.0 vs. 4.2 ± 1.8, p = 0.465), but three patients, all in the CC group, could not complete the procedure due to pain. CMBRFN in the MTC group was significantly faster than in the CC group (35.5 ± 7.3 min vs. 58.2 ± 14.8 min, p < 0.001), with less fluoroscopy time (167.6 ± 76.4 s vs. 260.8 ± 123.5 s, p = 0.004). Radiation dose was 8.95 ± 7.9 mGy in the MTC group and 11.53 ± 10.3 mGy in the CC group (p = 0.36). Rates of ≥50% NRS reduction were not significantly different between the two groups at 3 months, but at 6 and 12 months, they were significantly higher in the CC group. At 3, 6 and 12 months, rates of ≥30% NDI reduction were significantly higher in the CC group.

Conclusions: The MTC offers technical advantages compared to the CC for both the operator and the patient. However, CMBRFN with the multi-tined cannula seems less effective to treat neck pain than with the conventional cannula.