title: An alternative distal approach for the lumbar medial branch radiofrequency denervation: a prospective randomized comparative study.
abstract: BACKGROUND
  An alternative technique involving a "distal approach" can be used for lumbar medial branch radiofrequency denervation (LMBRFD). We described and assessed this technique by comparing it with a conventional tunnel vision approach in a prospective randomized trial.
  
  
  METHODS
  Eighty-two patients underwent LMBRFD by a distal (n = 41) or a tunnel vision approach (n = 41). The primary end point was a comparison of the mean difference in the change of 11-point numeric rating scale (NRS) scores of low back pain from entry to the scores at 1 month (NRS at baseline--NRS at 1 month) and at 6 months (NRS at baseline--NRS at 6 months) between the distal approach group and the tunnel vision approach group. The secondary end points were a change of NRS and the Oswestry disability index over time.
  
  
  RESULTS
  Thirty-four patients in each group had complete time courses. There were no statistically significant differences in the change of NRS scores between the groups at 1 month (corrected P = 0.19; 97.5% 2-sided confidence interval [CI], -1.37 to 0.37) and 6 months (corrected P = 0.53; 97.5% CI, -1.36 to 0.77). Patients in both groups showed a statistically significant reduction in NRS and Oswestry disability index scores from baseline to that of the scores at 1 and 6 months (all P < 0.0001, Bonferroni corrected). The procedure-related pain score was significantly lower in the distal approach group (P = 0.001; 99% CI, -2.00 to -0.23).
  
  
  CONCLUSIONS
  Patients who underwent LMBRFD by the tunnel vision or distal approaches showed significant pain relief at the 6-month follow-up. Less periprocedural pain was reported in the distal approach group. We consider that the distal approach provides an improved option for LMBRFD.
authors.affiliation: From the Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea; †Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Kyonggi, Republic of Korea; and ‡Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Jee Youn
authors.initials: JY
authors.lastname: Moon
authors.forename: Pyung Bok
authors.initials: PB
authors.lastname: Lee
authors.forename: Yong Chul
authors.initials: YC
authors.lastname: Kim
authors.forename: Seung Pyo
authors.initials: SP
authors.lastname: Choi
authors.forename: Woo Seog
authors.initials: WS
authors.lastname: Sim
mesh_terms: D000368:Aged; D000556:Ambulatory Surgical Procedures; D000772:Anesthesia, Local; D003714:Denervation / Q000379:methods*; D004185:Disability Evaluation; D023381:Endpoint Determination; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000601:surgery*; D008161:Lumbosacral Region / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009407:Nerve Block; D010147:Pain Measurement; D011446:Prospective Studies; D011846:Radio Waves; D016634:Radiosurgery / Q000379:methods*; D018401:Sample Size; D016896:Treatment Outcome; D021801:Zygapophyseal Joint / Q000601:surgery*
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