Abstract

BOADA PIE, S. et al. Ultrasound guided parasagittal obliqua aproach for lumbar medial branch block. Rev. Soc. Esp. Dolor [online]. 2015, vol.22, n.3, pp.134-141. ISSN 1134-8046.  https://dx.doi.org/10.4321/S1134-80462015000300008.

Objectives: The most used ultrasound guided medial branch block method requires the use of a biplane ultrasound technique. Using this technique the cannula is positioned not parallel to the medial branch by limiting their use to perform conventional radiofrequency. Using a sonographic parasagittal obliqua view allows placing the cannula parallel to the nerve, achieving sensory and motor stimuli and making possible radiofrequency above L5 lumbar segments. In the present study we determined the effectiveness of this new approach by using fluoroscopy and by obtention of sensory and motor stimuli. Material and methods: Thirty-one patients diagnosed with lumbar facet joint pain proposed for diagnostic medial branch blocks were studied. We describe four lumbar sequential sonographic views necessary to include patients in the study. Once obtained, the target point is located using a parasagittal oblique sonographic view to achieve the external face of the superior articular process and the more dorsal part of the transverse process. Puncture is performed guided in plane to place the tip at the junction between superior articular process and transverse process. Once the cannula located in the target proceeds to sensory stimulus 50 Hz and Motor 2 Hz to perform a cannula repositioning in case there were no stimuli. Once obtained either motor or sensory stimulus a caudal to craneal 30^o oblique projection is performed by fluoroscopy to check the location of the needle tip. Results: In 16% of patients cannot identify the four ultrasound views so the procedure is aborted. In the remaining 84% is achieved by placing the needle into the target point at 100% of the cases on the first attempt or by once a repositioning of the needle. Conclusion: Ultrasound oblique parasagittal view allows us a tangential approach to the lumbar medial branch with a high rate of success to position the radiofrequency cannula similar to when using fluoroscopy. The sonographic identification of the four windows described in the study allows us to screening tributary patient for ultrasound medial branch blocks.

Keywords : Facet joint; Lumbar facet joint pain; Lumbar medial branch block; Lumbar radiofrequency; Lumbar ultrasound.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )