Enraf Nonius Endomed 482, Руководство по эксплуатации

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at the Moscow State Academy. Kots used it for muscle strengthening in prosthesiology and in the training
of Russian cosmonauts. With this technique the electro stimulation is applied both to individual muscles
and to groups (either directly or via the nerve). In direct stimulation, a frequency of 2500 Hz was found to
produce the largest contraction, while the optimum frequency in indirect stimulation was 1000 Hz.
A specific feature of this type of muscle stimulation is that the alternating current is interrupted 50 times
per second. This results in a pulse train, comparable to the ‘burst’ in TENS. The total duration of the pulse
train is 20ms, giving a phase duration/phase interval ratio of 1:1. Kots uses a Burst frequency of 50 Hz,
approximately in the middle of the frequency spectrum used to produce tetanic contraction (40-80 Hz). In
addition to the 1:1 ratio, Kots also describes a phase duration/phase interval ratio of 1:5.
The amplitude should be increased until a powerful contraction is produced (from the motor stimulation
level up to the limit of tolerance). As with all muscle stimulation applications a Surge program can be
used, allowing the muscles to rest between exercise cycles.
Parameters:
Carrier Frequency
, expressed in kHz, is the base frequency of the alternating current.
Burst Frequency
, expressed in Hz, defines the repetition rate of the bursts.
Burst / Interval Ratio
, defines the ratio of the burst length to the interval between the bursts. The sum of
the burst and interval duration is the reciprocal of the burst frequency i.e. with a burst frequency set at 50
Hz and a burst / interval ratio of 1:5, the burst duration will be 20 * 1/6 = 3.3ms and the interval duration
will be 20 * 5/6 = 16.7ms.
Surge Program
can be used to adjust repeated sequences of contraction and rest periods. See
paragraph 8.2.5.6 for details.
4.1.3.5 Micro Current
Micro Current is a monophasic rectangular waveform with manually selectable or alternating polarity. See
fig 4.1.4.10 for a graphical representation. Many therapists prefer Micro Current therapy because of the
low current amplitudes used. Alternating polarity can be used to average out the DC component, thereby
reducing the formation of electrolysis by-products.
Parameters:
Frequency
, expressed in Hz, is the number of cycles per second.
Alternation mode
defines whether the polarity of the wave is automatically alternating or not.
Alternation Period
, expressed in s, defines the polarity reversal timing in the alternating mode.
Surge Program
can be used to adjust repeated sequences of contraction and rest periods. See
paragraph 8.2.5.6 for details. Surge programs are only available in the non alternating mode.
4.1.3.6 High Voltage
This current type has a twin peak monophasic waveform with a fixed duration of 64 µs between the two
voltage peaks. The amplitude is adjusted in volts rather than in mA. The short rise time and short duration
of each voltage peak (approximately 7 µs) is well suited to nerve stimulation and efficient discrimination
between sensory, motor and pain responses. The very short pulse duration of high voltage creates a
stimulation which is quite comfortable, and one which most patients can tolerate. The very short pulse
duration followed by a very long interpulse interval eliminates the formation of any appreciable chemical
or thermal effects in the tissue. High voltage is used for stimulating nerves and muscles, causing muscle
contractions. Examples for clinical use are to treat acute or chronic pain, edema absorption and ulcer
healing. Muscle contraction or motor response of isolated muscle groups, superficial or deep, can be
easily and comfortably stimulated. The relative comfort and depth of penetration may be the key for the
usefulness of high voltage stimulation in clinical conditions such as tendon transplants, joint mobilization
and muscle re-education.