J Korean Acad Rehabil Med.  2001 Apr;25(2):256-260.

Facilitation of Motor Evoked Potential by Stretching of Peripheral Nerve

• Ko MH
• Park EK
• Park SH
• Seo JH
• Kim YH

Abstract

OBJECTIVE
To investigate the effect of peripheral nerve stretching on motor evoked potentials (MEP) as a method of facilitation.
METHODS
Twenty three normal healthy volunteers were enrolled. Transcranial magnetic stimu lation (TMS) was applied to the contralateral scalp at 7 cm lateral to Cz using 90 cm round coil. Intensity of stimulation was adjusted to 90% of maximal stimulation intensity. Recording was done on the abductor pollicis brevis muscle in three different conditions; firstly resting state, secondly voluntary contraction of abductor pollicis brevis muscle, and lastly with stretching of median nerve. The onset latency and amplitude were obtained and compared between three conditions. RESULT: The amplitude of MEP was significantly increased in the condition with muscle contraction and peripheal nerve stretching compared with resting state. The latency was shortened in the condition with muscle contraction with statistical significance and with peripheral nerve stretching without significance.
CONCLUSION
We concluded that stretching of peripheral nerve can be used as a method of facilitation of MEP. This method is considered to be useful especially for the patients with motor paralysis or poor cooperarion for voluntary contraction.

Keyword

Transcranial magnetic stimulation; Motor evoked potentials; Peripheral nerve stretching

MeSH Terms

Evoked Potentials, Motor*
Healthy Volunteers
Humans
Median Nerve
Muscle Contraction
Nerve Expansion
Paralysis
Peripheral Nerves*
Scalp
Transcranial Magnetic Stimulation