ABSTRACT
The purpose of this work was the study of neuromuscular characteristics of healthy infants and infants with movement disorders by method of surface electromyography. 76 children at the age from 6 months till 3 years participated in the investigation: 61 with movement disorders (13--with ataxic form of cerebral palsy (CP), 48--with spastic form of CP) and 15 without movement disorders. Passive flexing and extending of knee and hip joints was conducted to the child in a recumbent position, EMG activity of the basic muscles groups of a hip and a shin was recorded. Characteristic properties of electromyographic activity were assessed with wavelet transform and subsequent analysis of obtained time dependencies. As a result of work the parameters connected with diagnosis of infants with movement disorders were revealed.
Subject(s)
Cerebral Palsy/physiopathology , Electromyography , Movement Disorders/physiopathology , Cerebral Palsy/diagnosis , Child, Preschool , Female , Humans , Infant , Male , Movement Disorders/diagnosisSubject(s)
Eye Movements/physiology , Neurophysiology/methods , Perception/physiology , Posture , Adult , Humans , Middle Aged , Restraint, PhysicalSubject(s)
Motor Neurons/physiology , Posture/physiology , Adult , Exercise Test , H-Reflex/physiology , Humans , Middle Aged , Muscle, Skeletal/physiologySubject(s)
Achilles Tendon/physiology , Neck Muscles/physiology , Postural Balance/physiology , Posture/physiology , Vibration , Adult , Electromyography/methods , Electromyography/statistics & numerical data , Humans , Middle Aged , Muscle, Skeletal/physiology , Reference Values , Signal Processing, Computer-Assisted , Time FactorsSubject(s)
Isometric Contraction/physiology , Muscle Relaxation/physiology , Adult , Humans , Linear Models , Middle Aged , Time FactorsABSTRACT
The measurement of damping of low-amplitude limb oscillations permits to evaluate the energy losses in passive human skeletal muscle during small length changes. The attenuation curve for the limb oscillations is quite different from the classical attenuation curve in the presence of viscous damping. Energy losses per oscillation cycle are practically frequency independent. Thus the damping properties of passive muscles at joint angular velocities up to 100% are due mostly to the velocity-independent resistance of "dry friction" type. The value of this "friction" is about 0.07 N per sm2 of muscle cross-section. The passive muscle also has marked thixotropy, as its resistance to small amplitude low velocity stretches strongly depends on time between stretches.
