title: Anatomical analysis of medial branches of dorsal rami of cervical nerves for radiofrequency thermocoagulation.
abstract: OBJECTIVE
  Cervical medial branch blocks are used to treat patients with chronic neck pain. The aim of this study was to clarify the anatomical aspects of the cervical medial branches to improve the accuracy and safety of radiofrequency denervation.
  
  
  METHODS
  Twenty cervical specimens were harvested from 20 adult cadavers. The anatomical parameters of the C4-C7 cervical medial branches were measured. The 3-dimensional computed tomography reconstruction images of the bone were also analyzed.
  
  
  RESULTS
  Based on cadaveric analysis, most of the cervical dorsal rami gave off 1 medial branch; however, the cervical dorsal rami gave off 2 medial branches in 27%, 15%, 2%, and 0% at the vertebral level C4, C5, C6, and C7, respectively. The diameters of the medial branches varied from 1.0 to 1.2 mm, and the average distance from the notch of inferior articular process to the medial branches was about 2 mm. Most of the bifurcation sites were located at the medial side of the posterior tubercle of the transverse process. On the analysis of 3-dimensional computed tomography reconstruction images, cervical medial branches (C4 to C6) passed through the upper 49% to 53% of a line between the tips of 2 consecutive superior articular processes (anterior line). Also, cervical medial branches passed through the upper 28% to 35% of a line between the midpoints of 2 consecutive facet joints (midline).
  
  
  CONCLUSIONS
  The present anatomical study may help improve accuracy and safety during radiofrequency denervation of the cervical medial branches.
authors.affiliation: From the *Department of Anesthesiology and Pain Medicine, †Anesthesia and Pain Research Institute, and ‡Department of Anatomy, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Tae Dong
authors.initials: TD
authors.lastname: Kweon
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Hye Yeon
authors.initials: HY
authors.lastname: Lee
authors.forename: Myung Hwa
authors.initials: MH
authors.lastname: Kim
authors.forename: Youn-Woo
authors.initials: YW
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059925:Anatomic Landmarks; D002102:Cadaver; D017115:Catheter Ablation / Q000379:methods*; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000294:innervation*; D003714:Denervation / Q000379:methods*; D004210:Dissection; D004564:Electrocoagulation / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted; D013127:Spinal Nerves / Q000033:anatomy & histology* / Q000601:surgery*; D014057:Tomography, X-Ray Computed