Accuracy of electromyography needle placement in cadavers: non-guided vs. ultrasound guided

Muscle Nerve. 2011 Jul;44(1):45-9. doi: 10.1002/mus.22008.

Abstract

Introduction: Accuracy of needle electromyography is typically ensured by use of anatomical landmarks and auditory feedback related to voluntary activation of the targeted muscle; however, in certain clinical situations, landmarks may not be palpable, auditory feedback may be limited or not present, and targeting a specific muscle may be more critical. In such settings, image guidance might significantly enhance accuracy.

Methods: Two electromyographers with different levels of experience examined 14 muscles in each of 4 fresh-frozen cadaver lower limbs. Each muscle was tested a total of eight times; four fine wires were inserted without ultrasound (US) guidance and four were inserted under US guidance. Overall accuracy as well as accuracy rates for the individual electromyographers were calculated.

Results: Non-guided needle placement was significantly less accurate than US-guided needle placement, particularly in the hands of less experienced electromyographers, supporting the use of real-time US guidance in certain challenging situations in the electromyography laboratory.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cadaver
  • Electromyography / instrumentation*
  • Electromyography / standards*
  • Humans
  • Muscle, Skeletal / diagnostic imaging*
  • Needles / standards*
  • Reproducibility of Results
  • Ultrasonography / methods
  • Ultrasonography / standards