this gives a brief overview of structure of neurons with classification of nerves. It also explains the myelinogenesis and properties of the neurons. this helps in basic understanding of nerve phys...
A nerve conduction study (NCS) is a medical diagnostic test commonly used to the ability of electrical conduction, of th e motor and sensory nerves of the human body. These tests are performed by medical specialists such as specialists in clinical neurophysiology, physiatrists (physical medicine and rehabilitation [PMR] physicians), and neurologists
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Motor NCS
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Sensory NCS F-wave study
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H-reflex study
Motor NCS
Sensory NCS
F-wave study
Motor NCS are Sensory NCS are F-wave study uses performed by performed by stimulation of a motor electrical stimulation of electrical stimulation of nerve and recording a peripheral nerve a peripheral nerve of action potentials and recording from and recording from a from the site of the a muscle supplied by purely sensory portion stimulating electrode in this nerve. of the nerve, such as the limb to the spinal on a finger. cord's ventral horn and back to the limb in the same nerve that was stimulated
H-reflex study H-reflex study uses stimulation of a nerve and recording the reflex electrical discharge from a muscle in the limb via proper reflex arc.
It involves the recording of nerve to the muscle
It involves the study of conduction with in the nerve itself
It involves the conduction b/w the nerve and spinal cord
Same as f-wave study
Only single nerve involved at a time
Same
Same
Involvesafferentand efferent nerves (i.e. those going towards and coming from spinal cord)
It is used for •
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Evaluating nerve injuries Fine nerve root compressions for evaluation of paraesthesia (numbness, tingling, burning) and/or weakness of the arms and legs
It is a technique by which the action potential of contracting muscle fibres and motor units are recorded and displayed. It has three phases: •
Input phase: includes electrodes to pick up
electrical potential from contracting muscle •
Processor phase: that amplifies small action
potentials •
Output phase: include the display and analysis
of electrical potential by visual and auditory means
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Diagnostic or clinical Electromyography: used
for the study of diseases of muscles, neuromuscular junctions and nerves. •
Kinesiological Electromyography: used to
study muscle activity to know the role of various muscles in specific activities.
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Electrodes Amplifier Display system
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Electrodes: are used in the input phase for
picking up electrical potentials from a contracting muscle. They are of following types: Surface electrodes Needle Electrodes Fine wire indwelling Electrodes Single fibre needle electrode Macro electrode Intra cellular electrode Multi lead electrode
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The Amplifier System: Converts the electrical
signal large enough to be displayed •
The display system: the amplified or
processed signal is displayed in a useful manner visually on screen for analysis
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Find diseases that damage muscle tissue, nerves, or the junctions between nerve and muscle. Find the cause of weakness, paralysis, or muscle twitching. Problems in a muscle, the nerves supplying a muscle, the spinal cord, or the area of the brain that controls a muscle can cause these symptoms.
