Effects of vibroacoustic therapy on reduction on reduction of muscle tonus

1. Definition of problems researched

This project is focused on the effects of vibroacoustic therapy on reduction of muscle tonus and improving a number of movements in patients with spasms.

At the “Stančić“ center about 100 out of a total of 400 users are diagnosed with cerebral paralysis. As mentioned above, these patients do not remain in their initial condition, as spasms turn into contractures very quickly. Patients with cerebral paralyis in this institution have so far been treated with physiotherapeautic treatments. Practical experience indicates that patients with painful spasms react negatively to physical approach by contracting and blocking the therapist’s activity. Based on that, we come to the conclusion that for the treatment of these patients a technique is needed by which the following would be achieved without physical pressure: 1) relaxation of the spasm and reduction of muscle tonus, 2) activation of non-functioning muscles.

Work with the users of our center is made more difficult by additional damage: mental retardation, sensory damage etc. The problem we will deal with in this research is finding the adequate treatment for patients with spastic forms of cerebral paralysis. Our tendency is to submit patients individually to certain stimuli and, using measuring methods, to determine which of the suggested stimuli is optimal for each of them.

Spasticity problems in our adult users are of such nature that we will be satisfied even with little shifts in spasm relaxation and prolonging the period of muscle tonus relaxation, reducing hyperventilation and anxiety. Our youngest users are the ones we would like to see more drastic improvements in.

1. Formulating hypotheses

Hypotheses:

1) low sound frequency of 40 Hz and soothing music positively affect muscle tonus reduction in patients with spastic form of cerebral paralysis

2) low sound frequencies of 40 Hz and soothing music have a positive effect on blood pressure normalization

2. Former research in this scientific field

Studies and research projects dealing with the effect of vibration on human organism are numerous, in this chapter I will mention some of them.

* In Roland and Nelsen’s study a stimulus of 100 Hz mechanical waves was measured on 8 points of the human hand, in normal and in brain damaged patients. Authors of the study find that the distribution of various shaking effects activates the Pacinian reflex in both healthy and in brain damaged patients. A relevant point of this study is that the mechanical wave, in addition to this, can activate a whole number of other receptors on the skin and below the skin tissue of examinees. During the study, the Pacinian reflex was isolated, the only known skin receptor, with the approximately same density everywhere and responding to high-frequency vibrations between 100 and 400 Hz.

Bergland and Bergland (1970) find that the intensity of perception is reduced with time, and 2-3 minutes are necessary for complete adaptation. In this experiment they use a sinusoidal sound of 250 cycles/second delivered to the tip of the finger through a round-shaped plastic button. They find that the decrease of the intensity of perception is greater with high levels of intensity and more time is necessary for adaptation. These authors also use the technique of infrared thermograph to show changes in temperature, and they also support the thesis according to which the vasodilation is caused by the inhibition of reflexes on the skin during external influence of vibrosensory mechanoreceptors. In former comparative experiments they found that the increase in temperature is in reverse correlation with skin temperature at the beggining of the stimulation.

Several separate experiments have confirmed the fact that heart rate and lung function varied irrelevantly during exposure of examinees to the stimuli. Research conducted in Japan confirms that low frequencies are felt on various parts of the body. For example, frequencies between 8 and 12 Hz can be felt on ears, breasts, buttocks and stomach; frequencies between 12 and 160 Hz are felt mostly on breasts; 200 Hz on legs, more than 250 Hz on ears.

3. Definition and history of VA therapy

Vibroacoustic theory can be defined as the use of music and sound (including sound and vibro stimuli) which are transmitted to the body in order to achieve physical and psychological therapeutic goals. The stimulus can include pulsation, low frequencies of pure tones – individually or in a group. The stimulus is transmitted to the body via loudspeakers built into the bed. This kind of therapy is very useful, and its application is on the rise. It is used by those who want to meet certain therapeutic goals, but with a difference in nature and manner of treatment.

The basic process of therapeutic intervention includes the patient lying on a bed with several built-in low-frequency loudspeakers. The sound is transmitted through the mattress or some other material so that it can directly reach the body.

One of the persons deserving most credit for the development of VA therapy is the Norwegian professor Olav Skille who started the use of music through huge loudspeakers fixated to a beanbag. He worked with psychologically and mentally impaired children in a school in Norway. Painful and uncomfortable spasms represented a big problem to the children in everyday life. Skille researched sound vibrations transmitted through the beanbag on which the children were lying, with the goal of reducing and relaxing muscle tonus, and general relaxation.

Experimenting with various styles of music, in his research Skille formed a hypothesis: low frequencies and slow relaxing music are effective in relaxation of the children. In his reports, but also in reports of medical nurses and physiotherapists, he noticed a certain success in the relaxation of children. Skille presented the methods and the principles of VAT on the 1. symposium of the International Society for Music and Medicine in 1982, titled „Low frequency messages“. He called it vibroacoustic therapy. It was a limited research considering absorption of sound in human organism, but in the Broner study we find that the body absorbs 2% energy of 100 Hz. There are also additional effects of the vibration from the contact created between the human body and the surface of the equipment. He develops recorded programs which can vary and be effective in the treatment of various problems.

It is important to know that the development of VAT as a treatment that includes music vibrations, or music and low frequencies and vibrations, was an inevitable part of music therapy. Even before its formulation the psychological and physiological effects of the music and the physical effect of the vibration and the infrasound were well documented and described both scientifically and from experience.

4. Defining goals and purpose of research

The research was devised as a repeated process of already executed and described treatments of vibroacoustic therapy with the goal of verifying placed data. The research evaluates the effect of vibroacoustic therapy with relaxing music and sinusoidal low-frequency pulse in comparison with the same music transmitted through a VA unit without the low-frequency pulsating tones.

The results of previous studies support the theory that muscle tonus can be reduced by vibration of general and specific area, although there is a certain degree of variability (e.g., in one user the improvement in stretching her right arm was 22% and 9% for the left arm, or the same measurement shows a large percentage of improvement in the level of movement one time, and another time the percentage is a lot smaller…)

The goal of the research is verifying the efficiency of VA therapy for the purpose of introducing it into regular rehabilitation practice, with the goal of maintaining and developing the ability to move muscles in patients with cerebral paralysis, which is important for both the prevention of further deterioration and the development and improvement of deformities of contracted limbs. In addition to reducing muscle tonus, improving flexion and extension of the limbs and improving the range of motion, we want to positively affect several other parametres as well.

Previous studies show that in a large number of patients the effect of VAT was positive on blood pressure, peristaltics, the increase in body temperature indicates a state of deep relaxation, challenging behavior, hyperventilation and various stereotypias are reduced, etc.

The goal of the research is, in accordance with that, verifying the results of previous studies, and the goal of vibroacoustic therapy is maintaining and developing movement in children and adults with cerebral paralysis, as well as preventing and correcting initial deformations. VAT implies a special methodology as a part of the whole prevention strategy in persons with cerebral paralysis, and the same therapy offers a large palette of improvement in other fields.

The purpose of the research is informing the therapists and expert personnel about the ways of using vibroacoustic therapy and providing an idea of eventual use in the rehabilitation program of our establishment.

. Identification and classification of variables

In order to precisely describe the variables which will be used in the research, it is essential to describe the equipment which will be used for the treatments (considering that it was made especially for this kind of therapy, in consultation with prof. Skille), the music and the experimental conditions.

6.1. Equipment

The equipment to be used in the research has been specifically made for VA therapy. To build a VA unit we used a bed 2 m long, 90 cm wide, 60 cm high. Under the bed we built in four movable sound boxes (dimensions 60x29x54) with two 10-inch loudspeakers in each of them, facing upwards. The sound boxes are positioned so that each of them affects a certain part of the body. The user is in a lying position for the duration of the treatment. The first sound box is positioned under the neck, shoulder girdle, the second one is under the lower part of the back and the upper part of the behind, the third one is under the lower part of the thighs and the fourth one is under the calves. The loudspeakers are movable because of the difference in the physionomy of the patients. This way, the distance between the loudspeakers can be adjusted and the treatment can be focused on a smaller zone. The built-in speakers are designed for reproduction of very low frequencies, while the sound box is designed to improve the existing characteristics. The surface of the bed is a matress made of perforated upholstered sponge 3 cm thick. On top of the matress there is an impermeable sheet (in case of incontinence), then an antidecubitus cushion and a blanket.

Conditions

We will repeat measurements with 20 chosen patients in 3 conditions:

Condition A – the user will be subjected to a 30-minute VA treatment consisting of soothing music and pulse with low, sinusoidal tones.

Condition B – the user will be subjected to a 30-minute B treatment consisting of music identical to the music in VAT and a special physiotherapeutic treatment afterwards;

Condition C – the user will be subjected to a 30-minute physical therapy treatment just like in condition A, but without the low sound frequencies.

Comparing conditions A and B the manipulated variable is the physical manipulation, and comparing conditions B and C the manipulated variable is the low-frequency sinusoidal tone.

Research outline

In this section the subjects chosen for research, research procedure and project schedule are described.

7.1. Subjects

Subjects chosen for this project are users of the “Stančić“ Center; out of a total of 33 subjects, 14 are female and 19 male, all of them diagnosed with mental retardation and multiple defects, and all of them with the spastic form of cerebral paralysis. In the initial phase every user will be subjected to one treatment in each condition, and then on the basis of data obtained they will be divided into separate groups (condition A, B or C). The initial status of the locomotor system and their health and psychological status has been noted for each of them and can be found in individual charts, together with monitoring tables and behavior monitoring lists. Before the first treatment for each of them, in addition to the inital status from the aspect of physical and health care, a list of measurements that are possible to be made on each of them has also been made.

Methods of obtaining data during research

During this research several methods of monitoring and measuring will be used:

– medical measurements of basic functions (blood pressure, body temperature, heart rate and respiratory amplitude)

– physiotherapeutic measurements which are used to determine the improvements in the range of motion and the decrease of muscle tonus

– monitoring the patients’ reactions by filming and writing down the reactions in the files

Medical measurements are made before and after every process for each patient and all measurements will be made in all the patients.

The conventional way of measuring the increase or the decrease in muscle tonus is by using an electromyograph, but as the use of self-adhesive electrodes causes an increase in anxiety and an increase in muscle tonus, an alternative way of measuring had to be found. Changes in the range of motion were measured on spinal mobility, limb flexion and stretching, so that the range of motion could be registered before and after the treatment. Blood pressure, heart rate and body temperature measurements will also be made before and after the treatment.

For each user a number of necessary physiotherapeutic measurements has been defined, considering the location of the spasm.

1. Setting

During the procedure period sessions were held on a defined schedule according to which every client came at a certain time, always on the same day of the week and to the same location. The staff conducting the procedure and the predefined process parametres did not change during that period.

The course of the research was affected by an epidemic of measles in the Center during January and February of 2004. During the epidemic the clients did not leave the infirmaries where they reside, so that period was used for data analysis, consultations with experts in the field and translation of professional literature. The epidemic lasted for 2 months, and happened after the end of the first procedure period. After that a food infection happened which also affected the course of the project, as it happened when the results of the placebo group were scheduled for measurement, so the measurements sould not be done on time. Therefore, instead of the planned three comparison groups there remained only two, but as those two key groups were measured and their results compared, the project can be considered successfully completed.

10. Discussion

10.1. Discussion of physiotherapeutic results

The results of this pilot project conducted on examinees with increased muscle tonus constantly show that when low sound frequencies were used together with soothing music, the reduction of muscle tonus and the improvement of the level of movement was greater than when they were not subjected to any kind of treatment. The results show an improvement in the level of movement in the group that was stimulated by low sound frequencies.

Before interpreting the results we have to point out the following fact. During the project the physiotherapeutic measurements were made by a single physiotherapist for all users, which is positive because of the unique approach and intensity of the measurement for all users. The only possible disadvantage is the relativity of the measurements made by a kinesiometric protractor, which is not accepted as a precise measuring instrument by the clinicians, but it is the only instrument accepted by the physiatrists. In this context, precise measurements can be made only by biomechanists using special computer programs and noninvasive electromyograph, which wasn’t possible with most of the examinees.

We have already contacted a couple of biomechanists, and we plan on working together in an upcoming period. In addition to that, the disadvantage of such measurements (with a protractor) in our users is that in a certain number of them we are not able to induce the required voluntary movement, so we measured the passive movement, done fully by the person doing the measurement. But as already mentioned, this is for now the only acceptable way of doing the measurements in our users.

Range of movement/[°] IRRS IRLS ERRS ERLS ERF ELF ERLL ELLL

(av – iv) tk

of the group treated 11,67 10,15 8,70 8,03 7,38 5,83 10,95 9,76

average value of the control group -3,89 -2,22 -2,22 -3,89 -3,33 -3,33 -4,67 -5,33

total improvement of the group treated 15,56 12,37 10,92 11,92 10,71 9,16 15,62 15,09

Table 10.1.1. Total improvement of the treated group shown by individual kinesiometric measurements

Table 10.1.1. shows average values of physiotherapeutic measurements in the group of treated examinees and the control group. The analysis of measurements and the comparison of measured average values show that the amplitude of movement in the treated group not only stayed the same, the range of movement in the joints has even improved (minimally up to 1,67°, and maximally up to 31,67°) in relation to the control group, where the range of movement decreased. The analysis of data in the examinees of the control group after a repeated measurement shows a progression of the spasm, and with that an increase of contracture in the joints.

Picture 10.1.1. Graphical presentation of total improvement of the treated group

The presented results show an improvement in the level of movement in the group that was subjected to vibration during 6 sessions. Analysis of the results, which show an improvement in the range of movement, is extremely encouraging, considering the fact that in the preliminary project we pointed out that in older users even maintaining a positive zero and stopping a negative growth is a great success. Likewise, it can be assumed that an improvement will be even bigger once we are able to introduce this procedure as a regular rehabilitational process and monitor, i.e. do the measurements over a minimum period of 2 years. Six sessions (that the examinees had during the past period), although an exceptionally short period of observation, show excellent results of this therapy.

Furthermore, the fact that this is a passive treatment where there are no forced and painfully uncomfortable physiotherapeutic corrections of joints affected by the spasms, during which the spasm often intensifies, and that the treatment consists of short periods of gentle acoustic vibrations passing through the muscle so that the examinee does not even feel it, lead us to conclusion that a positive result is guaranteed. There are numerous published papers that prove the effect of vibration, and like this project, they support the theory that spasms (previously located by an electromyograph) and spasticity can be reduced by vibration in both the general and the specific area.

An interesting fact is that the examinees individually show variability. For example, in some locations, like the lower leg, where it is possible to prove a large percentage of improvement, the reaction in the same examinee varies. This makes it possible to have an improvement of 0,00° in the left lower leg and of +26,67° in the right one, as it is the case in examinee number 14. This can be interpreted as a typical asymmetry often present in patients with CP. Likewise, not often, but still present is the fact that in physiotherapeutic measurements the difference in improvement can vary from one session to another. What should be done in such cases is locating the vibration on the areas in which a positive shift has been achieved.

The existing state shows that VA therapy can be very useful in prevention and treatment of pathological contractions of the musculature, which additionally improves the status of the motor system in persons with CP.

M. Ivoš, physiotherapist

10.2. Discussion of medical results

It has been noted in all the examinees that the temperature sometimes decreased or increased minimally, consequently, the effect of vibroacoustic therapy on body temperature is insignificant. Therefore, oscilations in temperature are so small that they can be considered physiological variations (they would be the same even without the effect of vibration).

As for blood pressure measurements, it is indicative that in all the examinees with elevated blood pressure there was a normalization after the session. Likewise, measurements show that in examinees whose body pressure values was within normal limits the values after the session were still within that range. Examinee number 14 has diagnosed arterial hypertension, and in all the sessions with him there was a decrease in body pressure value which has also been confirmed by authors worldwide. (references 1 and 2).

Picture 10.2.1. A representation of systolic and diastolic pressure in examinee 4 before and after VA therapy and ideal pressure values

Regarding heart rate measurements we can state that in only 8 out of 78 measurements the heart rate increased for more than 5 beats per minute, but four of those do not surpass physiological limits. Therefore it can be concluded that if the heart rate is an indicator of stress, fear, etc., that stress is reduced by application of VA therapy.

During all sessions no examinees showed any subjective (physiological) signs of discomfort, agitation or significant stress. According to the measurements, some of the examinees showed signs of excitement before the session, and after the session they were relaxed and calm. State of relaxation is also a prerequisite for successful administration of physical therapy in persons with CP and spasticity, so it is a success in itself.

D. Kramer, dr.

10.3. Discussion of rehabilitational therapy observations

During the pilot project the reactions and behavior of 14 examinees were constantly monitored, and that applies only to the ones who were subjected to condition A.

Observed were: facial expressions, body movement, level of relaxation, general behavior, verbal and nonverbal communication and reactions to the stimuli used during the session.

VA therapy had a positive effect on most of the patients – no routine unwanted forms of behavior were noticed, and by observing the earlier mentioned parameters it can be concluded that the examinees feel no discomfort, that is, they react positively to the stimuli used during the session.

Only in two of the examinees the intensity of psychomotor anxiety disabled participation in sessions and after two attempts they were excluded from the project.

In all the other examinees positive effects could be seen in: decreased logoroičnost (examinee number 9), reduced stereotypical behavior patterns (examinees 10 and 2), increased level of relaxation which was in some examinees manifested to such an extent that they fell asleep after first 10 minutes of the session (examinees 13 and and reduced level of psychomotor anxiety in general.

Based on the results of the observation it can be concluded that the application of VA therapy has a calming effect on the examinees which increases the quality of general behavior.

Positive experience with the pilot project supports the introduction of VA therapy as a regular rehabilitational procedure.

M. Bodor, prof.

11. Conclusion

During the pilot project there were many new situations, dilemmas and objective reasons for which the scheduled course was changed. The earlier mentioned epidemics and infections did not essentially disrupt the course of the project, except for the prolongation of the estimated time frame. Therefore, the continuity of the central part (condition A) was not hindered. During research, various problems appeared: the measurements were extremely hard to do in hyperactive, anxious or athetotic users, so they had to be repeated several times before and after sessions. Incontinence is a problem which made progress more difficult, especially in locating the spasm where it is necessary to take the clothes off the examinees to apply the electrodes. In addition to that, the room in which the sessions are done is not soundproof, which is very bad considering that, for example, the noise from the launderette nearby (and other sound interferences) has a negative effect on users in state of relaxation and light sleep. Still, this concerns only three of the examinees who did not want to have earphones on during the session. In addition to that, there is no air-conditioning in the room, so the body temperature measurements can be relativized, taking into consideration very high summer temperatures. Proper conditions would mean that the temperature in the room is always optimal and that there is a thermometer which measures room temperature.

There are many ways in which acoustic vibration can be put in service of our users. Considering the results obtained, I recommend that a group of users with diagnosed hypertension (regardless of the state of the locomotor system) is formed, and that their blood pressure during the VA process is measured over a certain period of time. In addition to that, the effect of classic physical therapy that would be applied immediately after a 20-minute VA treatment can be greater after relaxation in VA treatment. This treatment combination is called MMBP (Music Movement And Basic Physiotherapy) by authors worldwide. I recommend observation of VA treatment over a longer period of time, for example 2 years, as there is the possibility of adaptation of muscles to vibration, and the absence of positive effects of the process. The procedure in itself will go in the direction of equipment specialisation, so that a narrower specific area could be treated (for example, upper arm muscles), but that requires significant financial means. In terms of equipment of development of equipment, the best option would be to follow muscle reactions with an EMG, thus precisely determining the reaction of the muscle to the stimulus at any moment. The results we have obtained so far are clinically (because of measurements methods) and statistically (because of the number of users included) insufficiently interesting. That is why I recommend the inclusion of a bigger number of users (with hypertension, spasticity, inadequate behavior, anxiety…) in the treatment with various goals. Until now, only the advantages of low sound frequencies have been used, but high sound frequencies are equally applicable and useful.

The conlusion is that the VA treatment truly helps in prevention of muscle regression, normalizes blood pressure and helps in general relaxation of users. This doesn’t mean that it helps always and in all patients, so the measurements during the process must be done always and not just during research. This therapy can be just as useful or even more useful than other forms of treatment in a certain number of users, so I recommend that the VA treatment be made available to users of this Center. I hope that this project will motivate others to find new ways of helping users, and that more extensive and better research will be done, to the benefit of everybody involved.

Finally, I would like to express my satisfaction with the results obtained and with the cooperation of team members, without whom the realization of this project would not be possible.

Author of the project

Slavica Bevanda

12. Reference

1. Wigram, T., Dileo, C.: «Music vibration and health», by Jeffrey Books, 1997.

2. Kurtov, A.I.: «Vibroakustičeskoe vozdeistvie v kompleksnom lečenii boljnjih», Sankt Peterburg, 2003.

3. Petri, L.: «The physioacoustic method», Sibelius Academy, Department of music education, 2003.

4. «Akustika», str.18., Muzička enciklopedija

5. Heđever, M., Kovačić, G.: «Akustika glasa i govor», nedovršeni radni materijal, 1997.

6. Cvjetičanin, M., Mrkalj, R.: «Pregled preventivnih mjera obzirom na lokomotorni sustav djece preškolske dobi», Crikvenica, 1990.

7. Bevanda, S., Bodor, M., Ivoš, M., Kramer, D., ,: «Projekt vibracijsko – akustične terapije»

Submitted by Olav Skille