BTL Electrotherapy 4000 User manual

BTL-4000

Electrotherapy

USER‘S GUIDE

Page 1 of 36

110DA03/03/2008EN

CONTENTS:

1 GENERAL EFFECT OF ELECTROSTIMULATION ........................................................................................... 5

2 CLASSIFICATION OF ELECTROTHERAPEUTIC CURRENTS........................................................................ 6

2.1 Galvanic Current............................................................................................................................................ 6

2.2 Pulse Direct Current ......................................................................................................................................6

2.3 Alternating Current......................................................................................................................................... 6

2.3.1 TENS .......................................................................................................................................................7

2.3.2 Classic (Four-pole) Interference............................................................................................................... 7

2.3.3 Two-pole Interference .............................................................................................................................. 7

2.3.4 Isoplanar Interference .............................................................................................................................. 7

2.3.5 Dipole Vector Field................................................................................................................................... 8

3 EFFECTS OF ELECTROTHERAPY................................................................................................................... 9

3.1 Analgesic Effect............................................................................................................................................. 9

3.2 Myorelaxation and Spasmolytic Effect......................................................................................................... 10

3.3 Trophic Effect .............................................................................................................................................. 10

3.4 Antiedematous Effect................................................................................................................................... 11

3.5 Placebo Effect ............................................................................................................................................. 11

3.6 Deferring Effect............................................................................................................................................ 11

3.7 Contraindications for Electrotherapy............................................................................................................ 12

3.8 Symbols of Effects A-E-T-R-S ..................................................................................................................... 12

4 SETUP AND CONTROLS OF ELECTROTHERAPY .......................................................................................13

4.1 Common Parameters................................................................................................................................... 13

4.1.1 Output Mode .......................................................................................................................................... 13

4.1.2 Polarity................................................................................................................................................... 14

4.1.3 Therapy Time......................................................................................................................................... 14

4.1.4 Physiological Effects .............................................................................................................................. 14

4.2 TENS........................................................................................................................................................... 14

4.2.1 Type....................................................................................................................................................... 14

4.2.2 Pulse, Frequency, Pause....................................................................................................................... 14

4.2.3 Electro Parameters ................................................................................................................................15

4.3 2-pole, 4-pole, Isoplanar and Dipole Interference........................................................................................ 15

4.3.1 Carrier Frequency .................................................................................................................................. 15

4.3.2 Electro Parameters ................................................................................................................................15

4.4 Russian Stimulation..................................................................................................................................... 16

4.4.1 Carrier Frequency .................................................................................................................................. 16

4.4.2 Pulse Frequency, DF ............................................................................................................................. 16

4.4.3 Pulse Length (Electro Parameters) ........................................................................................................ 16

4.5 Mid-frequency Surges.................................................................................................................................. 16

4.5.1 Carrier Frequency .................................................................................................................................. 16

4.5.2 Pulse, Frequency, Pause....................................................................................................................... 16

4.5.3 Electro Parameters ................................................................................................................................16

4.6 Diadynamic Currents ................................................................................................................................... 17

4.6.1 Type....................................................................................................................................................... 17

4.6.2 Base....................................................................................................................................................... 17

4.6.3 Electro Parameters ................................................................................................................................17

4.7 Pulses: Rectangular, Triangular, Exponential and with Exponential Rise, Combined, Interrupted .............. 18

4.7.1 Type....................................................................................................................................................... 18

4.7.2 Pulse, Frequency, Pause....................................................................................................................... 18

4.7.3 Electro Parameters ................................................................................................................................18

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4.8 Stimulation Pulses ....................................................................................................................................... 18

4.8.1 Type....................................................................................................................................................... 18

4.8.2 Pulse, Pause.......................................................................................................................................... 18

4.8.3 Electro Parameters ................................................................................................................................19

4.9 Träbert Current, Leduc Current, Faradic Current, Neofaradic Current, H-waves......................................... 19

4.10 Galvanic Current.......................................................................................................................................... 19

4.10.1 Type....................................................................................................................................................... 19

4.11 Microcurrents............................................................................................................................................... 19

4.11.1 Type....................................................................................................................................................... 19

4.11.2 Pulse, Frequency, Pause....................................................................................................................... 19

4.11.3 Electro Parameters ................................................................................................................................20

4.12 Spastic Stimulation ...................................................................................................................................... 20

4.12.1 Pulse, Delay, (Frequency)...................................................................................................................... 20

4.13 Pulse Modulation ......................................................................................................................................... 20

4.13.1 Constant Frequency............................................................................................................................... 20

4.13.2 Random Frequency................................................................................................................................ 20

4.13.3 Burst....................................................................................................................................................... 20

4.13.4 Sine Surges ........................................................................................................................................... 20

4.13.5 Trapezoid Surges................................................................................................................................... 20

4.13.6 Symmetric Surges.................................................................................................................................. 21

4.14 Interference – Parameters ........................................................................................................................... 21

4.14.1 AMF and Spectrum ................................................................................................................................ 21

4.14.2 Frequency Sweep .................................................................................................................................. 21

4.15 Electrodiagnostics........................................................................................................................................ 22

4.15.1 Motor Point Detection............................................................................................................................. 22

4.15.2 Accommodation Coefficient ................................................................................................................... 22

4.15.3 I/t Curve .................................................................................................................................................22

4.16 Combined Therapies ................................................................................................................................... 23

4.16.1 Polarity of Ultrasound Head ................................................................................................................... 23

4.16.2 Setting Parameters of Combined Therapy ............................................................................................. 24

4.17 Specific Electrotherapy Settings .................................................................................................................. 24

4.17.1 Check of Contact of Electrodes.............................................................................................................. 24

4.17.2 Measuring of Electrodes ........................................................................................................................ 24

5 RECOMMENDATIONS FOR ELECTROTHERAPY ......................................................................................... 25

5.1 Use of Plate Electrodes ............................................................................................................................... 25

6 TECHNICAL PARAMETERS OF ELECTROTHERAPY .................................................................................. 26

6.1 Parameters of Particular Therapies – Currents ........................................................................................... 26

6.1.1 TENS ..................................................................................................................................................... 26

6.1.2 4-pole Interference................................................................................................................................. 26

6.1.3 2-pole Interference................................................................................................................................. 26

6.1.4 Isoplanar Interference ............................................................................................................................ 26

6.1.5 Interference - Dipole Vector ................................................................................................................... 27

6.1.6 Russian Stimulation ...............................................................................................................................27

6.1.7 Mid-frequency Surges (Amplitude-Modulated)....................................................................................... 27

6.1.8 Rectangular Pulses................................................................................................................................ 27

6.1.9 Triangular Pulses ................................................................................................................................... 28

6.1.10 Exponential Pulses, Pulses with Exponential Rise................................................................................. 28

6.1.11 Combined Pulses................................................................................................................................... 28

6.1.12 Stimulation Pulses (for Stimulations according to Electrodiagnostics) ................................................... 28

6.1.13 Interrupted Pulses.................................................................................................................................. 29

6.1.14 Träbert, Ultra-Reiz 2-5 ........................................................................................................................... 29

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6.1.15 Leduc ..................................................................................................................................................... 29

6.1.16 Faradic, Neofaradic................................................................................................................................ 30

6.1.17 H-wave................................................................................................................................................... 30

6.1.18 Diadynamics .......................................................................................................................................... 30

6.1.19 Galvanic Current (Iontophoretic) ............................................................................................................31

6.1.20 Microcurrents ......................................................................................................................................... 31

6.1.20 Spastic Stimulations (according to Hufschmidt) ..................................................................................... 31

6.1.22 High-voltage Therapy (HVT) .................................................................................................................. 31

6.2 Modulation of Currents ................................................................................................................................ 32

6.3 Frequency Sweep (Interference) ................................................................................................................. 32

6.4 Steps IN Setting Parameters ....................................................................................................................... 33

6.5 Maximum Intensity Values........................................................................................................................... 34

PAGE 4 OF 36

1 GENERAL EFFECT OF ELECTROSTIMULATION

Electrotherapy is one of the most widespread types of physical therapy (PT). When correctly indicated and
applied, it is very effective. However, it cannot be taken out of the context of comprehensive therapy, nor can it be
regarded as a cure-all.

Most of the physical procedures have similar effects and, depending on the parameters, some of them may be
dominant. The main effects are:

• analgesic,

• myorelaxation, trophic and antiedematous.

By selection of a procedure and its parameters, you can select one of the above-stated effects or their
combination.

Continuing education is a very important aspect of healthcare delivery. Many excellent resources are available
today to expand the user's knowledge of many aspects of electrical stimulation therapy. BTL recommends a
thorough review of this guide prior to operating the equipment.

GENERAL EFFECT OF ELECTROSTIMULATION | PAGE 5 OF 36

2 CLASSIFICATION OF ELECTROTHERAPEUTIC CURRENTS

2.1 GALVANIC CURRENT

Galvanic current (or “continuous”) is current of constant intensity. It is always DC. It is used mostly for
iontophoresis, or its trophic stimulating (hyperaemic) effect is utilized. A great disadvantage of galvanic current is
the risk of chemical damage to the tissue under the electrodes. The damage may be caused by the hydrochloric
acid which originates under the anode or by the soda lye which originates under the cathode. A similar danger of
tissue damage can also occur with any direct current (e.g. diadynamic).

Direct currents must not be used on patients with metallic implants!

At present, this current is often substituted by galvanic intermittent current. This current has the same effects
(galvanic component is 95 %) but thanks to interrupting the originally continuous intensity by the frequency 8 kHz,
it is better tolerated by patients. It is suitable especially for iontophoresis.

2.2 PULSE DIRECT CURRENT

Pulse direct current is current of variable intensity but with only one polarity. The basic pulse shape may vary. It
includes e.g. diadynamics (combination of pulse DC – "dosis" and galvanic current – "basis"), rectangular
(e.g. Träbert current), triangular and exponential pulses of one polarity.

Depending on the used frequency and intensity, it has stimulating, trophic and analgesic effects. Generally, direct
current with variable intensity has the same risks as galvanic current (corrosion of the skin surface) and therefore
requires careful observance of the correct procedure, especially the correlation between the applied intensity and
the length of application.

The main effect is stimulation, which is important especially below the cathode (green negative electrode).

2.3 ALTERNATING CURRENT

In comparison with DC, alternating current is safer and better subjectively tolerated by the patient. The basic
pulse shape again may be various – rectangular, triangular, harmonic sinusoidal, exponential or combined. It can
be alternating, symmetric or asymmetric. The DC component is always zero, which prevents chemical damage of
the skin under the electrodes.

Therefore, this current also allows long-term applications, even for patients with metal implants. Implanted
electronic stimulators such as pacemakers, etc. are indeed quite contraindicated. Nowadays, low-power pulses –
TENS (Transcutaneous Electrical Nerve Stimulation) and interference – are gaining ground among alternating
currents. Use of alternating currents in contact electrotherapy implies much lower stress on the tissue under the
electrode.

For these types of current, the capacitive component of skin resistance is involved, and also thanks to it these
currents are very well tolerated by patients.

CLASSIFICATION OF ELECTROTHERAPEUTIC CURRENTS | PAGE 6 OF 36

In general:

• short duration of the pulse improves the subjective perception,

• the zero average value (DC component) prevents chemical damage of the tissue,

• frequency and amplitude are responsible for the required therapeutic effect.

2.3.1 TENS

TENS = transcutaneous electrical nerve stimulation

Nowadays, a very prevalent group of currents which substitutes the standard applications of diadynamic currents,
Russian stimulation, etc. TENS pulses are low power and have zero DC component. Therefore, besides
suppression of chemical damage of the tissue, the risk of electrical damage of the tissue is also minimized.

As can be seen from their name, these currents are intended for the stimulation of nerve stems or nerve fibres.
Their major utilization is in the alleviation of pain, inhibition of itching, etc. The mechanism of their effect is most
often explained by the so-called gate theory of pain. Besides treating pain, these currents can also be effectively
utilized in electrogymnastics (stimulation of non-denervated muscles).

2.3.2 CLASSIC (FOUR-POLE) INTERFERENCE

Four electrodes are located crosswise. Two frequency signals with different frequencies f
the tissue. Their interference in the tissue induces a low-frequency surge in the centre of the cross; its frequency
is:

AMF = f

- fB.

A

This surge of the frequency AMF has a therapeutic effect; both basic currents of the frequency fA and fB are used
only for "transport" of the AMF surges to the tissue. The fA frequency is constant; changes in the fB frequency by
the value of the so-called Spectrum serve to change the resulting frequency AMF to the frequency
AMF + Spectrum. Interference has similar effects as low-frequency currents although it is carried by a current of
higher frequency and does not stress the tissue under the electrode so much. The carrier frequency of channels
ranges from 3.5 to 10 kHz. The higher this frequency, the better it is tolerated by the patient. The advantage of
four-pole interference is the in-depth aiming of the treated area and lower stress on the superficial skin. Therefore,
higher intensity values can be set than for the two-pole application.

2.3.3 TWO-POLE INTERFERENCE

According to the new recommended terminology, these groups should be called "bipolar-applied
amplitude-modulated mid-frequency currents"; however, owing to the length of this name, we are keeping to the
original one.

The resulting low-frequency current of the frequency AMF (or AMF + Spectrum) is created by the equipment.
Therefore, two electrodes are sufficient for its application. The absolute intensity values that can be reached are
lower than in classic interference (this current is more poorly tolerated by the patient than classic interference)
and at the same time the stress on the skin surface is higher than in classic interference.

and fB are brought to

A

Its advantage is that it can be applied by point electrode and thus can be effectively used in combination with
therapeutic ultrasound.

2.3.4 ISOPLANAR INTERFERENCE

A special form of four-pole interference where the additional modulation of both channels enables the treated area
to be distributed to the whole space of the current circuits’ interlacement. This implies that placing of individual
electrodes is much easier – they do not need to form a perfect cross anymore. The effect of these currents is very
diffuse, in-depth and delicate.

CLASSIFICATION OF ELECTROTHERAPEUTIC CURRENTS | PAGE 7 OF 36

2.3.5 DIPOLE VECTOR FIELD

Additional phase and amplitude modulation of the basic signals of four-pole interference enables only one
direction of the electric field’s action to be achieved (a so-called dipole is created in the tissue). In the direction of
this dipole, the modulation of the field reaches up to 100 %, in the other directions it is almost zero. You can either
rotate this dipole (abscissa) manually, and thus precisely aim the required effect of the therapy at the treated
tissue, or let it rotate automatically.

CLASSIFICATION OF ELECTROTHERAPEUTIC CURRENTS | PAGE 8 OF 36

3 EFFECTS OF ELECTROTHERAPY

3.1 ANALGESIC EFFECT

Pain is a multi-factor phenomenon and practice positively shows that various types of pain respond more or less
well to various physiotherapeutic, i.e. also electrotherapeutic procedures. There are several mechanisms of the
analgesic effect of electrotherapy – besides the well-known gate theory of pain there is also a proven increase in
the production of endogenous opiates. The analgesic effect is also supported by the trophic effects of the flowing
current. Timely myorelaxation removes muscular hypertone and thus also pain of myofascial origin. Since the
analgesic effect of electrotherapy is fundamental and most utilized, it shall be described in a little more detail.

Pain is usually simply defined as an unpleasant sensory and emotional experience connected with actual or
potential damage of tissue. We usually distinguish between acute and chronic pain. Acute pain is short-lasting
(maximum several days or weeks). It is caused by mechanical damage of the tissue or by a disease, comes
immediately after a painful stimulus and subsides when it ends; the intensity of pain depends on the intensity of
the stimulation. On the other hand, chronic pain is long-lasting (more than 3 months) or it recurs; its intensity does
not depend on the intensity of stimulation; emotions particularly play a leading role.

The now generally accepted theory of perception of pain is based on the assumption of the existence of a specific
sensory system which transfers information from pain receptors (nociceptors) to the central nervous system by
special preformed nerve paths. However, the process is in fact much more complicated and those interested can
learn about it in the available specialized literature.

To understand the effects of electrotherapy, it is important to understand especially the modulation factors which
can influence the perception and transfer of the painful stimulus:

• The first crucial modulation factor is described by the so-called gate theory of pain, which is based on the
presumption that the nervous mechanism in posterior medullary horns act as a small gate which lets through
only a limited flow of nervous impulses from the peripheral afferent fibres to the central nervous system,
depending on how much it is opened. Stimulation of some particular fibres can modulate the extent of the
gate’s opening or closing for pain and thus also increase or decrease the transfer of nociceptive information.
A similar gate system is supposed to exist also on the level of the thalamus.

• The other important modulation factor is described by the neuromodulation theory, which is based on the
analgesic effect of some substances belonging to the group of so-called neuromodulators, especially
endorphins and encephalins. These substances are produced in the central nervous system and according to
the mentioned theory they have crucial importance especially in the subjective perception of pain.

In any case, the analgesic effect of electrotherapy is used most often. To make PT of real benefit to the patient, it
is necessary to observe the following principles:

• Do not suppress the signalling and protective function of pain (which is especially important in acute pain!),
i.e. first decrypt the information being signalled by the pain, properly determine the diagnosis or at least a
preliminary hypothesis, and only then intervene against the pain. Pain modified by PT or analgesics can lose
its specificity insomuch that later it cannot be decrypted.

• Together with the application of analgesic PT, it is necessary to considerably reduce the administration of
analgesics. This rule is very important, owing to the possibility of relatively precise focusing of the analgesic
effect of PT (in contrast to the unfocused effect of medicaments) and possible undesired interaction between
PT and the medicaments.

• When choosing the type of PT, consider the expected effect (gate theory, endorphins).

EFFECTS OF ELECTROTHERAPY | PAGE 9 OF 36

• For chronic or recurrent complaints, do not obstinately apply various types of PT, but examine the locomotive
system (or get it examined by a specialist) – very often, the source of these complaints is far from the place
of projection of pain (catenation-generalization).

For the stimulation of thick, myelinized nerve fibres of A beta and delta types (gate theory), it is suitable to use
low-frequency currents of frequency 50 - 150 Hz (optimum 100 Hz) and intensity at or above threshold sensitivity.
This method is effective especially for acute and segmentally localised pains. For painful chronic syndromes, it is
most suitable to use low frequencies of 2 - 8 Hz and intensity at the highest tolerable level (up to the threshold of
pain); thus, thin fibres of the C type are stimulated (creation of endorphins). To achieve a combination of both
above-stated mechanisms of easing pain, use "burst modulation". The carrier frequency should be about 100 Hz,
burst frequency up to 10 Hz (even frequencies lower than 1 Hz are not exceptional). Currents with burst
modulation bring a cumulated analgesic effect. According to the depth of the required effect, the procedures can
be ordered as follows (from the most superficial to the deepest ones):

• analgesic effect of anelectrotonus (galvanic current)

• diadynamic currents LP and CP-ISO

• Träbert current

• TENS

• 2-pole interference (amplitude-modulated mid-frequency currents),

• 4-pole interference, isoplanar interference and vector fields

3.2 MYORELAXATION AND SPASMOLYTIC EFFECT

Especially after posturographic examination had proved that overall administration of so-called myorelaxancies
has a negative long-term influence on the body posture, the possibility of exact aiming at the hypertonic muscle
has been regarded as an especially valuable advantage of myorelaxation procedures. In the overall application of
myorelaxancies, there are first affected the phasic muscles, which have been already weakened due to the layer
syndrome. Later, or when a stronger dose is applied, there are also affected the tonic muscles and only at the
end, at the strongest dosage, are hypertonic muscles also positively affected. This effect lasts for several weeks
and affects the structure of the spine very negatively even after acute complaints have subsided.

Procedures with myorelaxation effect include therapeutic ultrasound, 2-pole interference with contour frequency
100 – 200 Hz, 4-pole interference currents and high-voltage therapy in the same frequency modulation band. For
small superficial muscles especially in the hands, paraffin can also be used.

A favourable side effect of myorelaxation is also the analgesic effect.

3.3 TROPHIC EFFECT

is caused by hyperaemia, which occurs in almost all types of PT (except cryotherapy). Since the mechanism of
hyperaemia in various types of PT is different, it is necessary to take these mechanisms into account so as to be
able to select the particular PT. Generally, galvanization can be recommended, especially longitudinal (capillary
hyperaemia, vessel eutonisation), low-frequency currents of frequency 30 - 60 Hz and intensity at or above the
threshold motor activity level (muscle micropump) or ultrasound, laser, polarized specified achromatic light,
vacuum-overpressure therapy, etc.

The trophic effect may be partly caused by the fact that most forms of PT, esp. laser, biolamp and
magnetotherapy, bring energy into the organism, to be used by cells (or other structures) for their activity.

The trophic hyperaemic effect is also usually connected with the analgesic effect.

EFFECTS OF ELECTROTHERAPY | PAGE 10 OF 36

3.4 ANTIEDEMATOUS EFFECT

is practically connected with hyperaemia, vessel eutonisation and higher capillary permeability. Therefore, the
therapies referred to as trophic are also antiedematous (see the previous paragraph).

3.5 PLACEBO EFFECT

Opponents of physical therapy tend to refer to its effects as placebo.

If PT is applied accidentally, without knowledge of its mechanism, accurate aiming and dosage (as often
happens), its effects can be called this. Exact verification of the effects of PT faces many problems.

• Owing to the fact that lege artis application of PT requires especially the patient's individuality and momentary
functional status to be taken into account (including the limbic system status, mood, muscular tonus, season
of the year, weather, motivation, attitude to problems, etc.) it is almost impossible to create a group for further
statistical processing. Creation of a control group is practically out of question.

• The effect of PT lies almost only in affecting the afferent system. The afferent system processes all data,
including visual, auditory, tactile and other analysers. Since a slight stimulus is very often sufficient to deviate
the organism from the existing functional balance (even pathological) and, using its enormous self-repairing
abilities, the organism helps itself, there cannot be carried out e.g. a blind experiment without at least
minimum excitation of the afferent system and/or higher components of CNS.

• Functional defects of the locomotive organs, which are the main positive effects of PT, tend to self-repair if
they are not prevented from that (e.g. by inappropriate pharmacotherapy). If correctly indicated, PT both
initiates and accelerates this self-repair, which indeed can be hardly proved exactly.

3.6 DEFERRING EFFECT

A "troublesome" patient is often invited for a check-up only after undergoing usually ten procedures and "hopefully
will be better then". This way of thinking is immoral, unethical and discreditable to a specialist, but nevertheless
most of the existing prescriptions of PT unfortunately belong to this category. In some surgeries patients are even
told that the effect of the chosen PT will become apparent only after several months (!), which means that the
physician fully relies on the body’s self-repair abilities.

Indication of PT should then not be based only on the diagnosis, especially if the diagnosis is confusing, e.g.
periarthritis humeroscapularis, etc.

The attending physician should know the answers to the following questions:

• What is the cause of the complaints, i.e. usually pain?

• Is the defect functional or organic?

• Where was the defect initiated – where is (are) the key area(s)?

• Which of the above-mentioned effects of PT is the most important for the patient at the moment?

• Is there not a risk of aggravation or organification of the functional defect after the chosen PT?

With the answers, the physician should choose the type, location, intensity, frequency and total number of
treatments, and, in relation to them, also the date of the check-up of the patient.

EFFECTS OF ELECTROTHERAPY | PAGE 11 OF 36