Abstract
The affect of muscle length and voluntary contraction upon compound muscle action potentials (CMAPs) in subjects with carpal tunnel syndrome (CTS) has been evaluated. Twenty-five hands in a CTS patient group and 29 hands in a normal subject control group were studied. The CMAPs from the abductor pollicis brevis induced by median nerve stimulation at the wrist were obtained for five thumb positions: neutral, abduction for shortening with and without contraction, and adduction for lengthening with and without contraction. Upon muscle shortening with relaxation, CMAP duration decreased in both groups, whereas waveform amplitude increased in the control group and showed no significant change in the CTS group. Muscle shortening with contraction afforded decreased CMAP duration and increased CMAP amplitude in both groups. Upon muscle lengthening with relaxation, both groups showed a reduction in CMAP amplitude and an increase in CMAP duration. Upon lengthening with contraction, CMAP duration decreased in the control group; in contrast, the CTS group showed further amplitude reduction and the waveform duration returned to the neutral value. These results demonstrate that, in patients with CTS, physiologic CMAP summations by muscle shortening or contraction may be less effective, whereas decreases in amplitude and increases in duration may be accentuated by lengthening and contraction.
| Original language | English |
|---|---|
| Pages (from-to) | 275-281 |
| Number of pages | 7 |
| Journal | Journal of Electromyography and Kinesiology |
| Volume | 15 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2005 Jan 1 |
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Keywords
- Carpal tunnel syndrome
- Compound muscle action potential
- Contraction
- Length
- Physiologic summation
ASJC Scopus subject areas
- Neuroscience (miscellaneous)
- Biophysics
- Clinical Neurology
Cite this
Physiologic changes of compound muscle action potentials related to voluntary contraction and muscle length in carpal tunnel syndrome. / Kim, Byung Jo; Date, Elaine S.; Park, Byung Kyu; Choi, Bryan Y.; Lee, Sang Heon.
In: Journal of Electromyography and Kinesiology, Vol. 15, No. 3, 01.01.2005, p. 275-281.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Physiologic changes of compound muscle action potentials related to voluntary contraction and muscle length in carpal tunnel syndrome
AU - Kim, Byung Jo
AU - Date, Elaine S.
AU - Park, Byung Kyu
AU - Choi, Bryan Y.
AU - Lee, Sang Heon
PY - 2005/1/1
Y1 - 2005/1/1
N2 - The affect of muscle length and voluntary contraction upon compound muscle action potentials (CMAPs) in subjects with carpal tunnel syndrome (CTS) has been evaluated. Twenty-five hands in a CTS patient group and 29 hands in a normal subject control group were studied. The CMAPs from the abductor pollicis brevis induced by median nerve stimulation at the wrist were obtained for five thumb positions: neutral, abduction for shortening with and without contraction, and adduction for lengthening with and without contraction. Upon muscle shortening with relaxation, CMAP duration decreased in both groups, whereas waveform amplitude increased in the control group and showed no significant change in the CTS group. Muscle shortening with contraction afforded decreased CMAP duration and increased CMAP amplitude in both groups. Upon muscle lengthening with relaxation, both groups showed a reduction in CMAP amplitude and an increase in CMAP duration. Upon lengthening with contraction, CMAP duration decreased in the control group; in contrast, the CTS group showed further amplitude reduction and the waveform duration returned to the neutral value. These results demonstrate that, in patients with CTS, physiologic CMAP summations by muscle shortening or contraction may be less effective, whereas decreases in amplitude and increases in duration may be accentuated by lengthening and contraction.
AB - The affect of muscle length and voluntary contraction upon compound muscle action potentials (CMAPs) in subjects with carpal tunnel syndrome (CTS) has been evaluated. Twenty-five hands in a CTS patient group and 29 hands in a normal subject control group were studied. The CMAPs from the abductor pollicis brevis induced by median nerve stimulation at the wrist were obtained for five thumb positions: neutral, abduction for shortening with and without contraction, and adduction for lengthening with and without contraction. Upon muscle shortening with relaxation, CMAP duration decreased in both groups, whereas waveform amplitude increased in the control group and showed no significant change in the CTS group. Muscle shortening with contraction afforded decreased CMAP duration and increased CMAP amplitude in both groups. Upon muscle lengthening with relaxation, both groups showed a reduction in CMAP amplitude and an increase in CMAP duration. Upon lengthening with contraction, CMAP duration decreased in the control group; in contrast, the CTS group showed further amplitude reduction and the waveform duration returned to the neutral value. These results demonstrate that, in patients with CTS, physiologic CMAP summations by muscle shortening or contraction may be less effective, whereas decreases in amplitude and increases in duration may be accentuated by lengthening and contraction.
KW - Carpal tunnel syndrome
KW - Compound muscle action potential
KW - Contraction
KW - Length
KW - Physiologic summation
UR - http://www.scopus.com/inward/record.url?scp=14844320838&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=14844320838&partnerID=8YFLogxK
U2 - 10.1016/j.jelekin.2004.09.002
DO - 10.1016/j.jelekin.2004.09.002
M3 - Article
VL - 15
SP - 275
EP - 281
JO - Journal of Electromyography and Kinesiology
JF - Journal of Electromyography and Kinesiology
SN - 1050-6411
IS - 3
ER -