Ultrasound and nerve stimulation-guided L5 nerve root block.
METHODS
Case series.


OBJECTIVE
Evaluation of ultrasound and nerve stimulation-guided L5 nerve root block technique.


BACKGROUND
Ultrasound-guided peripheral nerve block has become clinically applied. However, selective lumbosacral nerve root block is conducted under radiographic guidance, which involves patients and operators being exposed to radiation. In addition, it cannot be carried out easily during outpatient visits or at the bedside. We conducted L5 nerve root block, which is one of the most common lumbosacral nerve root block under ultrasonic guidance, using electrical nerve stimulation.


METHODS
We assessed the effectiveness of ultrasound and nerve stimulation-guided L5 nerve root block on 78 patients with L5 radicular syndrome. To compare ultrasonic guidance using electrical nerve stimulation with radiographic guidance, we used a contrast agent and assessed its distribution.


RESULTS
After nerve block, decreased sensation at L5 neural region and diminished/fully resolved pain was observed in all patients except for 3 in whom nerve block could not be conducted as their articular process protruded laterally. Concerning the response to stimulation, all except for these 3 felt the tapping sensation at their L5 neural regions, but no contraction of muscles was observed. The number of patients who showed an extraneural, paraneural, and intraneural pattern on contrast radiography was 71, 4, and 0, respectively.


CONCLUSIONS
Ultrasound-guided L5 nerve root block using electrical nerve stimulation is a safe and effective method.
Sato
Masaki
M
Department of Orthopaedic surgery, Omigawa general hospital, Chiba, Japan. s-masaki@navy.plala.or.jp
Simizu
Sumito
S
Kadota
Ryo
R
Takahasi
Hirosi
H
D000328:Adult; D000368:Aged; D000779:Anesthetics, Local; D003287:Contrast Media; D004558:Electric Stimulation / Q000295:instrumentation / Q000379:methods; D004594:Electrophysiology / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation / Q000379:methods*; D009407:Nerve Block / Q000379:methods*; D011843:Radiculopathy / Q000000981:diagnostic imaging / Q000188:drug therapy*; D011859:Radiography / Q000379:methods; D013126:Spinal Nerve Roots / Q000000981:diagnostic imaging / Q000187:drug effects; D016896:Treatment Outcome; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods*
D000779:Anesthetics, Local; D003287:Contrast Media