Position accuracy and electromyographic responses during head reposition in young adults with chronic neck pain.
The head reposition test is traditionally used to examine the proprioceptive sensitivity of the neck. The aim of this study was to investigate the position accuracy and corresponding cervical electromyographic (EMG) responses of the neck pain subjects during sagittal head-to-neutral tasks. Twelve young subjects with chronic neck pain and twelve young healthy subjects were recruited. The position accuracy was measured by the constant error, variable error, and root mean square error of joint angles during head-to-neutral tasks in flexion and extension directions. Surface EMG of neck flexors and extensors were analyzed by the voluntary response index, including the similarity index (SI) and electromyographic magnitude (MAG) of muscle groups. The normalized average integration of EMG activity (NAIEMG) of individual muscle was also calculated. The results showed: (1) significantly larger constant error and root mean square error but similar variable error in patients compared with controls, (2) smaller SI but similar MAG in patients compared with controls, (3) greater synergistic/antagonistic NAIEMG in patients than controls. The findings suggested that young adults with chronic neck pain exhibit proprioceptive dysfunction and altered EMG pattern during voluntary sagittal neck motions. This study provides guidelines which could lead to the development of therapeutic exercise programs.
Cheng
Chih-Hsiu
CH
Department of Physical Therapy, Graduate Institute of Rehabilitation Science, Chang Gung University, Taoyuan, Taiwan, ROC.
Wang
Jaw-Lin
JL
Lin
Jiu-Jenq
JJ
Wang
Shwu-Fen
SF
Lin
Kwan-Hwa
KH
D000328:Adult; D002908:Chronic Disease; D005260:Female; D006257:Head / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009119:Muscle Contraction; D009334:Neck Muscles / Q000503:physiopathology*; D019547:Neck Pain / Q000175:diagnosis* / Q000503:physiopathology*; D011187:Posture / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity