TY - JOUR
T1 - Reduced force steadiness in women with neck pain and the effect of short term vibration
AU - Muceli, Silvia
AU - Farina, Dario
AU - Kirkesola, Gitle
AU - Katch, Frank
AU - Falla, Deborah
N1 - Copyright © 2010 Elsevier Ltd. All rights reserved.
PY - 2011/4
Y1 - 2011/4
N2 - This study compares neck force steadiness in women with neck pain and controls and the way this is influenced by short term vibration of the neck. In the first experiment, 9 women with chronic neck pain and 9 controls performed 10-s isometric cervical flexion at 15N. Intramuscular EMG was recorded from the sternocleidomastoid muscle. In the second experiment, 10 women with neck pain and 10 controls performed 10-s isometric cervical flexion at 25% of their maximal force before and after vibration to the neck (bursts of 50Hz with duration 20, 40, 60 and 120s). Surface EMG was acquired from the sternocleidomastoid and splenius capitis. In both experiments, force steadiness was characterized by the coefficient of variation (CoV) and the relative power in three frequency subbands (low: 0-3Hz; middle: 4-6Hz; high: 8-12Hz) of the force signal. Women with neck pain exhibited decreased force steadiness (Exp 1: patients 3.9±1.3%, controls 2.7±0.9%, P<0.05; Exp 2: patients 3.4±1.2%, controls 1.7±0.6%, P<0.01) which was associated with higher power in the low-frequency band (patients 71.2±9.6%, controls 56.7±9.2%, P<0.01). Following vibration, CoV (2.6±1.1%, P<0.05) and the power in the low-frequency band of the force signal decreased (63.1±13.9%, P<0.05) in the patient group. These effects were not present in controls. Motor unit behavior and surface EMG amplitude were similar between groups. In conclusion, women with neck pain have reduced force steadiness, likely due to alterations in Ia afferent input. Vibration, which modulates Ia afferent input, increases force steadiness in patients with neck pain.
AB - This study compares neck force steadiness in women with neck pain and controls and the way this is influenced by short term vibration of the neck. In the first experiment, 9 women with chronic neck pain and 9 controls performed 10-s isometric cervical flexion at 15N. Intramuscular EMG was recorded from the sternocleidomastoid muscle. In the second experiment, 10 women with neck pain and 10 controls performed 10-s isometric cervical flexion at 25% of their maximal force before and after vibration to the neck (bursts of 50Hz with duration 20, 40, 60 and 120s). Surface EMG was acquired from the sternocleidomastoid and splenius capitis. In both experiments, force steadiness was characterized by the coefficient of variation (CoV) and the relative power in three frequency subbands (low: 0-3Hz; middle: 4-6Hz; high: 8-12Hz) of the force signal. Women with neck pain exhibited decreased force steadiness (Exp 1: patients 3.9±1.3%, controls 2.7±0.9%, P<0.05; Exp 2: patients 3.4±1.2%, controls 1.7±0.6%, P<0.01) which was associated with higher power in the low-frequency band (patients 71.2±9.6%, controls 56.7±9.2%, P<0.01). Following vibration, CoV (2.6±1.1%, P<0.05) and the power in the low-frequency band of the force signal decreased (63.1±13.9%, P<0.05) in the patient group. These effects were not present in controls. Motor unit behavior and surface EMG amplitude were similar between groups. In conclusion, women with neck pain have reduced force steadiness, likely due to alterations in Ia afferent input. Vibration, which modulates Ia afferent input, increases force steadiness in patients with neck pain.
KW - Adult
KW - Female
KW - Humans
KW - Muscle Contraction
KW - Muscle, Skeletal
KW - Muscular Diseases
KW - Neck Pain
KW - Treatment Outcome
KW - Vibration
KW - Comparative Study
KW - Journal Article
U2 - 10.1016/j.jelekin.2010.11.011
DO - 10.1016/j.jelekin.2010.11.011
M3 - Article
C2 - 21195628
SN - 1050-6411
VL - 21
SP - 283
EP - 290
JO - Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology
JF - Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology
IS - 2
ER -