Wrist – Hand (2L muscle)

Surface Recording Technique, Study to the Second Lumbrical (2L) Muscle
  • Giuliano Gentili
  • Mario Di Napoli

Original Settings

Sensitivity was 500 μV/division, low-frequency filter was 3 Hz, high-frequency filter was 10 kHz, sweep speed was 2 ms/division, and the machine used was a 2-channel Medelec Synergy EMG machine. Duration of pulse was not specified.


This study was performed in the supine position.


Using the technique [ 1] by Preston and Logigian [ 2], the authors placed the active electrode (A) slightly lateral to the midpoint of the third metacarpal space, over the belly (motor point) of both the second lumbrical (2L) and interossei (INT) muscles (Fig. 1). The reference (R) was placed over a bony prominence of the proximal interphalangeal joint of digit II. The motor point to the 2L was identified by an initial negative deflection with the fastest rise time. Surface recording was made with monopolar recording electrodes. The ground (G) electrode position was not mentioned in the text; it could be placed on the palm or on the dorsum of the hand. The figure shows the...


  1. 1.
    Therimadasamy AK, Li E, Wilder-Smith EP (2007) Can studies of the second lumbrical interossei and its premotor potential reduce the number of tests for carpal tunnel syndrome? Muscle Nerve 36:491–496PubMedCrossRefGoogle Scholar
  2. 2.
    Preston DC, Logigian EL (1992) Lumbrical and interossei recording in carpal tunnel syndrome. Muscle Nerve 15:1253–1257PubMedCrossRefGoogle Scholar
  3. 3.
    Bodofsky EB, Wu KD, Campellone JV et al (2005) A sensitive new median-ulnar technique for diagnosing mild carpal tunnel syndrome. Electromyogr Clin Neurophysiol 45(3):139–144PubMedGoogle Scholar
  4. 4.
    Mandel JD, Wertsch JJ, Park TA et al (1992) Early and late median premotor potentials. Muscle Nerve 15:1185Google Scholar
  5. 5.
    Dumitru D, King JC (1995) Median/ulnar premotor potential identification and localization. Muscle Nerve 18:518–525PubMedCrossRefGoogle Scholar
  6. 6.
    Park TA, Del Toro DR (1995) Generators of the early and late median thenar premotor potentials. Muscle Nerve 18:1000–1008PubMedCrossRefGoogle Scholar
  7. 7.
    Hasegawa O, Matsumoto S, Gondo G et al (2004) Recordings of nerve conduction studies representing characteristics of motor and sensory nerves. Clin Electroencephalogr 46:62–64Google Scholar
  8. 8.
    Takahashi N, Takahashi O, Ogawa S et al (2006) What is the origin of the premotor potential recorded from the second lumbrical? Muscle Nerve 34:779–781PubMedCrossRefGoogle Scholar
  9. 9.
    Bland JDP (2000) A neurophysiological grading scale for carpal tunnel syndrome. Muscle Nerve 23:1280–1283PubMedCrossRefGoogle Scholar
  10. 10.
    Kodama M, Sasao Y, Tochikura M et al (2012) Premotor potential study in carpal tunnel syndrome. Muscle Nerve 46:879–884PubMedCrossRefGoogle Scholar
  11. 11.
    Padua L, Lo Monaco M, Gregori B et al (1997) Neurophysiological classification and sensitivity in 500 carpal tunnel syndrome hands. Acta Neurol Scand 96:211–217PubMedCrossRefGoogle Scholar
  12. 12.
    Masakado Y, Abe L, Kawakami M et al (2008) The origin of the premotor potential recorded from the second lumbrical. Electromyogr Clin Neurophysiol 48:9–11PubMedGoogle Scholar
  13. 13.
    Masakado Y, Kodama M, Takahashi O et al (2011) The origin of the premotor potential recorded from the second lumbrical muscle in normal man. Clin Neurophysiol 122:2089–2092PubMedCrossRefGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Giuliano Gentili
    • 1
  • Mario Di Napoli
    • 1
  1. 1.Neurological ServiceS. Camillo de’ Lellis General HospitalRietiItaly

Personalised recommendations