Comparison of MRI with EMG to study muscle activity associated with dynamic plantar flexion

Thomas B. Price, Gary Kamen, Bruce M. Damon, Christopher A. Knight, Brooks Applegate, John C. Gore, Ken Eward, Joseph Signorile

Research output: Contribution to journalArticle

50 Citations (Scopus)

Abstract

This study compared magnetic resonance imaging (MRI) and surface electromyography (EMG) to evaluate the effect of knee angle upon plantar flexion activity in the triceps surae muscles [medial & lateral gastroenemius (MG, LG) and the soleus (SOL)]. Two weight & height matched groups performed identical protocols, twelve (6M, 6F) in the MRI group, twelve (8M, 4F) in the EMG group. Subjects plantar flexed dynamically for 2 min at 25% of 1-repetition maximum voluntary contraction (1-RM). Exercise was performed with the knee extended (0° flexion), flexed (90°), and partially flexed (45°). In the MRI group spin-echo images were acquired before and immediately following each exercise session. T2 times, calculated at test and after exercise by fitting the echoes to a monoexponential decay pattern with a least-squares algorithm, were compared with EMG data. In the EMG group a bipolar electrode was used to collect samples were from the MG, LG, SOL, and anterior tibialis (TA) during exercise at each knee angle, MRI also examined the peroneus (PER). At 0° flexion MRI demonstrated a significant post-exercise T2 increase in the MG (p ≤ 0.001), LG (p ≤ 0.001), and PER (p ≤ 0.01), with no T2 change in the SOL or TA. At 90° flexion there was a significant T2 increase in the SOL (p ≤ 0.001) with no significant T2 change in the MG, LG, PER, or TA. At 45° T2 increased significantly in the SOL (p ≤ 0.001) and LG (p ≤ 0.05), but not the MG, PER, or TA. EMG produced similar results with the exception that there was significant activity in the TA during the relaxation cycle of the 90° protocol. We conclude that: 1) Soleus activity is measurable by MRI; and 2) MRI and EMG produce similar results from different physiological sources, and are therefore complementary tools for evaluating muscle activity.

Original languageEnglish
Pages (from-to)853-861
Number of pages9
JournalMagnetic Resonance Imaging
Volume21
Issue number8
DOIs
StatePublished - Oct 1 2003

Fingerprint

electromyography
Electromyography
Magnetic resonance
muscles
magnetic resonance
Muscle
physical exercise
Magnetic Resonance Imaging
Imaging techniques
Muscles
Knee
echoes
Least-Squares Analysis
Exercise Test
contraction
repetition
Electrodes
Research Design
Weights and Measures
cycles

Keywords

  • Electromyography
  • EMG
  • Exercise
  • Motor unit activation
  • MRI

ASJC Scopus subject areas

  • Biophysics
  • Clinical Biochemistry
  • Structural Biology
  • Radiology Nuclear Medicine and imaging
  • Condensed Matter Physics

Cite this

Comparison of MRI with EMG to study muscle activity associated with dynamic plantar flexion. / Price, Thomas B.; Kamen, Gary; Damon, Bruce M.; Knight, Christopher A.; Applegate, Brooks; Gore, John C.; Eward, Ken; Signorile, Joseph.

In: Magnetic Resonance Imaging, Vol. 21, No. 8, 01.10.2003, p. 853-861.

Research output: Contribution to journalArticle

Price, TB, Kamen, G, Damon, BM, Knight, CA, Applegate, B, Gore, JC, Eward, K & Signorile, J 2003, 'Comparison of MRI with EMG to study muscle activity associated with dynamic plantar flexion', Magnetic Resonance Imaging, vol. 21, no. 8, pp. 853-861. https://doi.org/10.1016/S0730-725X(03)00183-8
Price, Thomas B. ; Kamen, Gary ; Damon, Bruce M. ; Knight, Christopher A. ; Applegate, Brooks ; Gore, John C. ; Eward, Ken ; Signorile, Joseph. / Comparison of MRI with EMG to study muscle activity associated with dynamic plantar flexion. In: Magnetic Resonance Imaging. 2003 ; Vol. 21, No. 8. pp. 853-861.
@article{fd350f8fb24041f5acc5a72ad9316721,
title = "Comparison of MRI with EMG to study muscle activity associated with dynamic plantar flexion",
abstract = "This study compared magnetic resonance imaging (MRI) and surface electromyography (EMG) to evaluate the effect of knee angle upon plantar flexion activity in the triceps surae muscles [medial & lateral gastroenemius (MG, LG) and the soleus (SOL)]. Two weight & height matched groups performed identical protocols, twelve (6M, 6F) in the MRI group, twelve (8M, 4F) in the EMG group. Subjects plantar flexed dynamically for 2 min at 25{\%} of 1-repetition maximum voluntary contraction (1-RM). Exercise was performed with the knee extended (0° flexion), flexed (90°), and partially flexed (45°). In the MRI group spin-echo images were acquired before and immediately following each exercise session. T2 times, calculated at test and after exercise by fitting the echoes to a monoexponential decay pattern with a least-squares algorithm, were compared with EMG data. In the EMG group a bipolar electrode was used to collect samples were from the MG, LG, SOL, and anterior tibialis (TA) during exercise at each knee angle, MRI also examined the peroneus (PER). At 0° flexion MRI demonstrated a significant post-exercise T2 increase in the MG (p ≤ 0.001), LG (p ≤ 0.001), and PER (p ≤ 0.01), with no T2 change in the SOL or TA. At 90° flexion there was a significant T2 increase in the SOL (p ≤ 0.001) with no significant T2 change in the MG, LG, PER, or TA. At 45° T2 increased significantly in the SOL (p ≤ 0.001) and LG (p ≤ 0.05), but not the MG, PER, or TA. EMG produced similar results with the exception that there was significant activity in the TA during the relaxation cycle of the 90° protocol. We conclude that: 1) Soleus activity is measurable by MRI; and 2) MRI and EMG produce similar results from different physiological sources, and are therefore complementary tools for evaluating muscle activity.",
keywords = "Electromyography, EMG, Exercise, Motor unit activation, MRI",
author = "Price, {Thomas B.} and Gary Kamen and Damon, {Bruce M.} and Knight, {Christopher A.} and Brooks Applegate and Gore, {John C.} and Ken Eward and Joseph Signorile",
year = "2003",
month = "10",
day = "1",
doi = "10.1016/S0730-725X(03)00183-8",
language = "English",
volume = "21",
pages = "853--861",
journal = "Magnetic Resonance Imaging",
issn = "0730-725X",
publisher = "Elsevier Inc.",
number = "8",

}

TY - JOUR

T1 - Comparison of MRI with EMG to study muscle activity associated with dynamic plantar flexion

AU - Price, Thomas B.

AU - Kamen, Gary

AU - Damon, Bruce M.

AU - Knight, Christopher A.

AU - Applegate, Brooks

AU - Gore, John C.

AU - Eward, Ken

AU - Signorile, Joseph

PY - 2003/10/1

Y1 - 2003/10/1

N2 - This study compared magnetic resonance imaging (MRI) and surface electromyography (EMG) to evaluate the effect of knee angle upon plantar flexion activity in the triceps surae muscles [medial & lateral gastroenemius (MG, LG) and the soleus (SOL)]. Two weight & height matched groups performed identical protocols, twelve (6M, 6F) in the MRI group, twelve (8M, 4F) in the EMG group. Subjects plantar flexed dynamically for 2 min at 25% of 1-repetition maximum voluntary contraction (1-RM). Exercise was performed with the knee extended (0° flexion), flexed (90°), and partially flexed (45°). In the MRI group spin-echo images were acquired before and immediately following each exercise session. T2 times, calculated at test and after exercise by fitting the echoes to a monoexponential decay pattern with a least-squares algorithm, were compared with EMG data. In the EMG group a bipolar electrode was used to collect samples were from the MG, LG, SOL, and anterior tibialis (TA) during exercise at each knee angle, MRI also examined the peroneus (PER). At 0° flexion MRI demonstrated a significant post-exercise T2 increase in the MG (p ≤ 0.001), LG (p ≤ 0.001), and PER (p ≤ 0.01), with no T2 change in the SOL or TA. At 90° flexion there was a significant T2 increase in the SOL (p ≤ 0.001) with no significant T2 change in the MG, LG, PER, or TA. At 45° T2 increased significantly in the SOL (p ≤ 0.001) and LG (p ≤ 0.05), but not the MG, PER, or TA. EMG produced similar results with the exception that there was significant activity in the TA during the relaxation cycle of the 90° protocol. We conclude that: 1) Soleus activity is measurable by MRI; and 2) MRI and EMG produce similar results from different physiological sources, and are therefore complementary tools for evaluating muscle activity.

AB - This study compared magnetic resonance imaging (MRI) and surface electromyography (EMG) to evaluate the effect of knee angle upon plantar flexion activity in the triceps surae muscles [medial & lateral gastroenemius (MG, LG) and the soleus (SOL)]. Two weight & height matched groups performed identical protocols, twelve (6M, 6F) in the MRI group, twelve (8M, 4F) in the EMG group. Subjects plantar flexed dynamically for 2 min at 25% of 1-repetition maximum voluntary contraction (1-RM). Exercise was performed with the knee extended (0° flexion), flexed (90°), and partially flexed (45°). In the MRI group spin-echo images were acquired before and immediately following each exercise session. T2 times, calculated at test and after exercise by fitting the echoes to a monoexponential decay pattern with a least-squares algorithm, were compared with EMG data. In the EMG group a bipolar electrode was used to collect samples were from the MG, LG, SOL, and anterior tibialis (TA) during exercise at each knee angle, MRI also examined the peroneus (PER). At 0° flexion MRI demonstrated a significant post-exercise T2 increase in the MG (p ≤ 0.001), LG (p ≤ 0.001), and PER (p ≤ 0.01), with no T2 change in the SOL or TA. At 90° flexion there was a significant T2 increase in the SOL (p ≤ 0.001) with no significant T2 change in the MG, LG, PER, or TA. At 45° T2 increased significantly in the SOL (p ≤ 0.001) and LG (p ≤ 0.05), but not the MG, PER, or TA. EMG produced similar results with the exception that there was significant activity in the TA during the relaxation cycle of the 90° protocol. We conclude that: 1) Soleus activity is measurable by MRI; and 2) MRI and EMG produce similar results from different physiological sources, and are therefore complementary tools for evaluating muscle activity.

KW - Electromyography

KW - EMG

KW - Exercise

KW - Motor unit activation

KW - MRI

UR - http://www.scopus.com/inward/record.url?scp=0242664233&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0242664233&partnerID=8YFLogxK

U2 - 10.1016/S0730-725X(03)00183-8

DO - 10.1016/S0730-725X(03)00183-8

M3 - Article

C2 - 14599535

AN - SCOPUS:0242664233

VL - 21

SP - 853

EP - 861

JO - Magnetic Resonance Imaging

JF - Magnetic Resonance Imaging

SN - 0730-725X

IS - 8

ER -