title: Ultrasound-guided periradicular injections in the middle to lower cervical spine: an imaging study of a new approach.
abstract: OBJECTIVE
  The objective of this study was to show the efficacy of ultrasound in facilitating the performance of a simulated cervical periradicular injection in cadavers.
  
  
  METHODS
  A total of 40 ultrasound-guided examinations at 4 levels (C3 to C7) were performed on 4 embalmed cadavers. The cervical spinal nerves were located with ultrasound. First, the transverse process of each level was taken as a sonoanatomic landmark. The most lateral aspect of the transverse process of the seventh cervical vertebra was then established as the reference point. Ipsilateral distances (A, B, C, and D) between this point and each one of the transverse processes of the cervical spine up to the third vertebra were then computed. Subsequently, coronal computed tomography (CT) scans were taken to verify these distances. In a second part, a spinal needle was advanced under ultrasound guidance to the spinal nerves C5 to C8 on both sides of one cadaver. The exact placement of the needle tips was checked by CT.
  
  
  RESULTS
  The transverse processes were identified in all cadavers. In 5 attempts, a depiction of the spinal nerves was not possible. Ultrasound and CT provided the same mean measurements of 1.1 cm, 2.1 cm, 3.1 cm, and 4.1 cm for distances A, B, C, and D, respectively. All 8 needle tips were placed within 5 mm dorsal to the spinal nerve and less than 5 mm away from the posterior tubercle of each level's transverse process, as also verified by CT.
  
  
  CONCLUSIONS
  This preclinical study suggests that ultrasound is a useful guiding tool for periradicular injections in the cervical spine.
authors: Clinics of Neurosurgery, Medical University of Innsbruck, Austria.
authors: Klaus
authors: K
authors: Galiano
authors: Alois Albert
authors: AA
authors: Obwegeser
authors: Gerd
authors: G
authors: Bodner
authors: Martin Cornelius
authors: MC
authors: Freund
authors: Hannes
authors: H
authors: Gruber
authors: Herbert
authors: H
authors: Maurer
authors: Reinhold
authors: R
authors: Schatzer
authors: Franz
authors: F
authors: Ploner
mesh_terms: D002574:Cervical Vertebrae / Q000000981:diagnostic imaging*; D006801:Humans; D007278:Injections, Spinal / Q000379:methods*; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography