한국전문물리치료학회지 2017년 24권 2호 37-47 ISSN (Print) 1225-8962, ISSN (Online) 2287-982X

Phys Ther Korea 2017;24(2):37-47 https://doi.org/10.12674/ptk.2017.24.2.037

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뒤통수밑근 이완기법과 병행된 고주파 심부투열이 만성 긴장성 두통 환자들의 압통과 목 가동성 및 기능장애에 미치는 영향

이형렬1, 심재훈2, 오덕원3

1새하늘정형외과의원 물리치료실, 2백석대학교 보건학부 물리치료학과, 3청주대학교 보건의료대학 물리치료학과

Effects of High-frequency Diathermy Integrated into Suboccipital

Release on Tenderness and Neck Mobility and Disability in

People with Chronic Tension-type Headache

Hyoung-ryeol Lee1, BHSc, PT, Jae-hun Shim

2, PhD, PT, Duck-won Oh

3, PhD, PT

1Dept. of Physical Therapy, Saehaneul Orthopedic Surgery Clinic2Dept. of Physical Therapy, Division of Health Science Baekseok University3Dept. of Physical Therapy, College of Health Science, Cheongju University

Abstract1)

Background: Active trigger points (TrPs) of the suboccipital muscles greatly contribute to the

occurrence of chronic tension-type headache, with increased sensitivity of TrPs and facilitated referred pain.

Objects: This study aimed to investigate whether the integration of high-frequency diathermy into

suboccipital release is more beneficial than the use of suboccipital release alone.

Methods: Thirty subjects were assigned to either experimental group-1 (EG-1) to undergo suboccipital

release combined with high-frequency diathermy (frequency: 0.3 ㎒, and electrode type: resistive electronic

transfer), or EG-2 to undergo suboccipital release alone, or the control group (CG) with no intervention,

with 10 subjects in each group. The assessment tools included the headache impact test 6 (HIT-6),

perceived level of tenderness, neck disability index, and neck mobility. Intervention was performed for 10

minutes, twice per week, for 4 weeks, and measurements were performed before and after the interventions.

Results: The between-group comparison of the post-test values and changes between pretest and

post-test showed significant differences for all parameters at p<.05, except for the left-to-right lateral

bending range. In the post hoc test, EG-1 showed significant differences for the parameters in comparison

with the CG, while no significant differences in the perceived tenderness level, on both temporal regions,

were found between EG-2 and CG. Furthermore, the HIT-6 score and perceived tenderness level, in the

right temporal region, showed significant differences between EG-1 and EG-2. In the within-group

comparison, EG-1 and EG-2 appeared to be significantly different between pretest and post-test (p<.05),

except for the perceived tenderness level in the right temporal region, with significance for the EG-1 group

only (p<.05).

Conclusion: These findings suggest that the suboccipital release technique may be advantageous to

improve headache, tenderness, and neck function and mobility, with more favorable effects with the

incorporation of high-frequency diathermy.

Key Words: High-frequency diathermy; Neck function; Suboccipital release; Tension-type headache.

Corresponding author: Jae-hun Shim clinicalpt@bu.ac.kr

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Headache is the most common kind of pain and it is a major health problem that leads to significant pain, physical disability, and cause a large cost (Stovner et al., 2007). Steiner (2014) reported that about 46% of the population has active headache disorders, and the WHO defines headache as one of the top 10 threats to human health (Bendtsen and Jensen, 2006). In particular, tension-type headache is a pain in the head and neck that can be caused by a variety of causes, but it is known to be a major muscle problem (Stovner et al., 2007).In addition to pain, chronic tension-type headaches represent other disorders, such as decreased neck motion range and sleep disturbances (Fernández, 2007), and it also reduces job performances and increases stress of working people. These affects negatively in the quality of life by interfering work and life, social life and leisure activities (Monzani et al., 2016). In addition, those who complain of tension headaches have a relatively increased number of active myofascial trigger points that cause pain in the suboccipital muscles (Fernández et al., 2006).Treatments for tension headaches can be divided into drug and non-drug therapy. However, taking painkillers as a drug therapy for longer than three months can make the treatment harder and could lead to a medication-overuse headache (Stover et al. 2007). Therefore, it is very important to find ways to reduce pain effectively without resortingto drugs in the treatment of chronic tension-headaches. Several approaches are being introduced in recent studies to replace drug therapies with regards to chronic tension-headaches (Espí-Lopez et al., 2016). Manual therapies such as myofascial release are frequently performed in the clinical site to alleviate the side effects of drug treatment (Mense & Gerwin, 2010). Myofascial Release is an effective treatment method used by clinicians to relax tension and ease pain (Ajimsha, 2011). Since the active myofascial trigger points of suboccipital soft tissue are considered as a cause of chronic tension-headaches, many of the therapists who work at the clinic have continuously studied the effects of relaxation techniques and manual therapy (Fernández et al., 2014). The application of manual therapy to the muscles of suboccipital region and around the neck helps to improve headache and head and neck function (Fernández et al., 2006; Moraska et al., 2015), and furthermore, it has been shown to be positive and effective in improving the quality of life (Espi-Lopez

Ⅰ. Introduction

et al., 2016). In addition to the manual therapy like myofascial-release, one of the treatments that many physiotherapists use for muscle relaxation and pain control is the high-frequency diathermy. High-frequency therapy machine generates a safe level of friction from the body to help muscle relaxation and ease pain. High-frequency diathermy is effective and non-invasive way to treat tension-headaches by applying heat waves to the deep tissue by using of rotary motion of polarized molecules through electromagnetic waves, and the twisting mechanism of non-polarized molecules (Shim, 2008). And the increase in local tissue temperature contribute to various physiological effects such as reducing deep somatic pain, ease of muscle contraction, and reduction of joint stiffness. Furthermore, because the pulsation period of the high-frequency current is very short, it does not stimulate the sensory nerves and motor nerves, so it has the advantage of heating certain parts of the body without causing discomfort or muscle contraction (Ganzit, 2000). The application of high-frequency diathermy to degenerative neck patients helps reduce neck pain and improve neck mobility (Pernía, 2009), effective in reducing the pain of acute back pain (Letizia et al., 2010), and also ease the edema of sprained joint (Melegati et al., 2003). Generally, high-frequency diathermy is used in clinical areas aimed at reducing pain in each part of the body (Pernía, 2009). However, there is still a lack of research on the effects of high-frequency diathermy on reducing headache, and there is no research on the advantage of it if integrated into suboccipital release. Since the goal of high frequency therapy is a relaxation by increase temperature of the deep tissue, we can also think that it will be effective for tension headache, but there's only a little amount of researches to prove the efficacy of the treatment. Thus, the purpose of this study is to prove the efficacy of high-frequency diathermy by comparing the effects of suboccipital release alone and the one integrated with high-frequency diathermy. The hypothesis of this study is that when coupled with suboccipital release and high-frequency diathermy, the tenderness, joint movement range, and functional level will be further enhanced than when applying suboccipital release alone.

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1. Subjects

This study was conducted on 30 patients with chronic tension-type headache. The subjects were randomly assigned to 10 each of following three groups.-EG-1: Applying relaxation techniques with high-frequency diathermy-EG-2(experimental group-2): Applying suboccipital release only - CG(congtrol group) And the subjects were chosen by following :(1) People who were diagnosed with chronic tension headaches according to the criteria of the International Headache Society.(People have headaches for 15 days/month lasting 3 months or more.)(2) People who have headaches caused from the tension of suboccipital muscles.(People have referred pain when press trigger points for 10 seconds.)(3) People who have no orthopedic or psychological problems. Those who suffer from trauma and those who are pregnant are excluded from the subject. Prior to the experiments, the subjects were described in whole process and safety then we received written consent from all subjects.

2. Evaluation MetheodsA. Headache Impact Test-6(HIT-6)

For HIT-6, we used the headache impact test chart - Korean edition. HIT-6 consists of six questions to measure pain, social function, role function, cognitive function, psychological pain, and vitality. If a subject answered: "Never have such a thing" = 6 points “Rarely yes” = 8, “Sometimes” = 10, “Very often” = 11, “Always” = 13 pointsTotal scores are distributed from 36 up to 78, higher points means the higher severity of headache. More than 60 points mean having a very serious disability in her/his daily life, 56~59 indicates a significant disturbance, 50~55 points to some degree of disability, less than 49 points means a small or insignificant condition in daily life. And the people who scored more than 50 points are advised to consult with doctor for medical care.

B. Neck Disability Index(NDI)For the measurement, we used NDI – Korean edition. The NDI questionnaire consists of 10 questions. It evaluates the following 10 items; pain, headaches, driving, lifting, reading, concentration, sleep, daily life, working life, and leisure. The index is designed to measure the pain and functional disability of a subject's neck, with allocating 10 points to each questionnaire, indicating magnitude of the problems. Points 0~4 indicate no problem, 5~14 for minor problem, 15~24 points are functionally disabled, 25~34 indicates severely disabled,

Ⅱ. Method

over 35 means completely disabled.

C. Pressure Pain Threshold of headache areas and suboccipital muscles

For the measurements, Algometer(Fabrication enterprised, NY, USA) was used. The Algometer measures the thresholds of pain by the pressing-value of handpiece. The Pressure Pain Threshold indicates the value of pressure at the moment that the simple feeling of pressure changed to discomfort or pain when we press the soft tissue of a subject by handpiece. The measurement was taken while a subject seated comfortably in chair and the knee joints were kept at 90°. Then the examiner held a subject’s head with one hand, while the other measure by pressing the area by Algometer. The measurement of the threshold of headache area was taken in 2cm in front of tragus, where the headache occurs frequently due to referred-pain of the suboccipital muscles. The measuring area of the suboccipital muscles is the part of the linea nuchae inferior of occipital bone where the rectus capitis posterior minor muscle is, particularly, a trigger point that occur referred pain when press for 10 seconds. We measured the points by the Algometer. Place the Algometer on the examination area, measure the pressure level(lb/㎠) and record when the subject say he/she feel discomfort or pain. Headache area measurements were performed on each side of the head then put the average value.

D. Range of MotionFor the measurements, Goniometer(Preston, Oklahoma, USA) was used. The motion of the neck was measured by flexion and extension, left and right rotation, and lateral bending range. In the measurement of flexion and extension, the Goniometer was installed at the sagittal plane on the top of the head where the two ears meet and standardized by his/her nose under the circumstance of allowing a subject to maintain seating comfortably with ensuring the knee joint at 90°. For lateral flexion, Goniometer was placed at the frontal plane. For the rotation, a subject was laid in the supine position and we put Goniometer on his/her forehead. The flexion and extension of the neck was calculated by sum of the angles of flexion and extension. Rotation and lateral flexion were calculated by sum of the angles of both sides as well. The inspection sequence was executed randomly, all the ranges were measured three times of each movement, and the average was used for the results.

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3. Controls and Procedures

A. Suboccipital Release

We applied the manual therapy that used for

active myofascial trigger points which caused

suboccipital muscles pain due to tension-headaches.

It is consisted of two steps:

① While a subject was laid in the supine position,

the therapist put his hand under the subject’s

suboccipital region. Bend his metacarpophalangea

joint as 90° and straight the interphalangeal joint,

place his fingertips on the back of the skull,

positioned between the bones of the head and 1st

and 2nd bone of the neck, to support the lower

end of the head of the subject. In this posture, the

pressure of the affected area can be induced by

the weight of the subject's head (Figure 1-A).

② We let the subject to pull his/her chin towards

its neck, as the suboccipital muscles relaxed, at

the same time, the therapist hang up the lower

occipital by his fingers to give distraction-force in

direction of the head (Figure 1-B).

- Put 1 minute for the first step and 2 minutes for

the second, without interval between the two

steps. Total of 3 minutes in a routine, take 3

routines per a subject, put 30 seconds interval

between each routines.

B. High Frequency Diathermy

This group is consisted of 10 chronic tension-headache

patients and we applied high frequency diathermy

integrated into suboccipital release for 4weeks

(2times per week), putting 10 minutes per a

treatment. For this treatment, we used WINBACK

(Villeneuve Loubet France) which have strap-typed

electrode and return-pad plate (Figure 2), with

frequency as 0.3 MHz.High-frequency therapy

transfers heat by using CET(capacity electric

transfer) or RET (resistive electric transfer). CET

transfers heat to superficial and soft tissues that

have high electrolyte content. Meanwhile, RET

isconcentrated in heat transfer to in-depth and

hard tissues such as tendons, joints, and bones. In

this study, we used RET which is transfers heat

in-depth and doesn’t have discomfort feeling in

circumstance of continuous stimulate in one area,

controlling the strength from 0 to 100%. Starting

from 10%, we increased the strength until before a

subject feel discomfort. Average strength was

40%. RET heatgenerates between electrodes and

return-plate. We put return-plate under a patient’s

upper back, near suboccipital muscles, and the

therapist wore RET-bracelet(electrodes) on his

fore-arm (Figure 3). Treatment conducted as very

same as the suboccipital release therapy in EG-2.

We only controlled a strength of the frequency

when patients feel discomfort due to overheat.

A B

Figure 1. Use of suboccipital release technique. (A) palpation of subocciptal region and application of sustained pressure, and (B) distaction of subocciptal region.

Figure 2. Equipment of high - frequency diathermy (radio frequence therapeutique).

Figure 3. Application of high-frequency diathermy diathermy during suboccipital release. Physical therapist weared the strap-typed electrode in the middle of forearm (circle) and return-pad plate was positioned under patients’ upper back (square in dot line).

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C. Procedures

Before control, subjects of three groups were

tested their level of pain by HIT-6, pressure pain

threshold of headache areas and suboccipital muscles

by Algometer, range of motion by Goniometer,

functional disability by NDI. Both of EG-1 and EG-2

controlled to be conducted 2 times per week, 10

minutes per treatment, total of 4 weeks of

suboccipital release technique. The difference of

EG-1 is the therapist would wear the beracelet-

electrodes. Treatments were conducted by a

physical therapist who has clinical background

over high frequency therapy and with clinical

experience more than five years. For the subjects

of CG, we didn’t apply any treatment for 4 weeks

then measured them again (Figure 4).

4. Analysis

The data we collected was analyzed by SPSS

18.0(SPSS Inc., Chicago, IL, USA). For comparison

of general characteristics of the groups, we used

one-way analysis of variance(one-way ANOVA). In

the before/after cases of HIT-6 scores, pressure-pain

levels, NDI scores, and motion ranges, we used

Paired T-test. One-way ANOVA was used for

1. General Characteristics of the Subjects

30 chronic tension-type headache patients were

participated. EG-1 consisted of 3 male and 7 female,

EG-2 was 2 male and 8 female, CG was made up with

1 male and 9 female subjects. There were no big

differences of characteristics between groups. Please

refer Table 1 about the general characteristics.

2. Comparison of HIT-6 and Tenderness

Please refer Table 2. There were significant

differences in HIT-6 scores and pressure pains of left

temporal region and both-side’ suboccipital region at

EG-1 and EG-2 (p<5%), and difference of pressure

pain on right temporal region was only meaningful in

EG-1 (p<5%). Also, the HIT-6 scores and pressure

pains in temporal regions and suboccipital regoins

were different significantly between the groups

(p<5%). In the post-hoc test, all the variables showed

Ⅲ. Result

Figure 4. Diagram of the study (EG-1: integration of high-frequency diathermy into suboccipital release technique, EG-2: suboccipital release technique alone, CG: control group, HIT-6: Head impact Test-6, NDI: Neck Disability Index).

compare the effects of group controls. In the

post-hoc test, we conducted Scheffe' method. To

verify statistical significance, the significance level

was set to α=5%.

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except left-right lateral bending range in all

groups (p<5%). In the post-hoc test, all variables

of EG-1 showed significant differences in a

comparison with CG in NDI score, flexion-extension

range, and left-right rotation range (p<5%). EG-2 has

the differences in flextion-extension and left-right

rotation by comparison with CG (p<5%). In the

comparison of before/after, there were significant

differences in all variables except left-right lateral

bending range (p<5%). And in the post-hoc test,

both of EG-1 and EG-2 showed a big difference in

a comparison with the CG in all variables.

aexperimental group-1: integration of high-frequency heat therapy into suboccipital release, bexperimental group-2: suboccipitalrelease alone, ccontrol group, dmean±standard deviation, ehead impact test-6.

Table 1. General characteristics of subjects

significant differences between EG-1 and CG (p<.05),

and EG-2 has significant differences with CG in all

parts except both temporal regions (p<5%). Also,

there were big differences on before/after between

three groups (p<5%). In the post-hoc test, EG-1

showed big differences in HIT-6 score and pressure

pain on right temporal region than EG-2 (p<5%).

3.Comparison of NDI and neck mobility

Please refer Table 3. There were significant

differences of NDI scores and neck mobilities in

both of EG-1 and EG-2 (p<5%). Also in post-test,

there were meaningful differences in all variables

Table 2. Comparison of the outcome of tenderness in pre and post-test among three groups (Unit: lb/cm2)

aexperimental group-1: integration of high-frequency heat therapy into suboccipital release, bexperimental group-2: suboccipitalrelease alone, ccontrol group, dmean±standard deviation, ehead impact test-6, fdifference between pre-and post-test, significant difference in a comparison with the control group (p<.05), significant difference in a comparison with the EG-2EG-2 group (p<.05).

According to Headache Classification Committee of the International Headache Society(2013), the tension-headache is the most common type of headaches (Steiner et al., 2014). For the treatment, drug therapy is the most common way. But if overdose, there is a possibility that chronic daily headache will be occurred (Millea & Brodie, 2002). So nowadays, there are some other ways are used instead of drug therapy in clinical sites (Eisenberg et al., 2001). Therefore, in this study, we have been practice to see the effects of high frequency diathermy integrated into suboccipital release on tenderness and neck mobility and disability in people with chronic tension-type headache for 4 weeks. Since there were no study about this in Korea and worldwide, this study may has sufficient clinical significance. The high frequency diathermy integrated into suboccipital release in chronic tension headache patients showed significant improvements in tenderness and neck mobility and disability, and specially, there were a significant differents in HIT-6 scores between integrated one and sole one. One of the symptoms of chronic tension- headache patients is a pattern of pain caused from myofascial trigger points of head, neck and shoulders (Fernández, 2007). When the muscle-contractures are formed on the trapezius and sternocleidomastoid, they induce

Table 3. Comparison of the outcome of NDI (neck disability index) and neck mobility in pre and post-test among three groups (Unit: degree)

aexperimental group-1: integration of high-frequency heat therapy into suboccipital release, bexperimental group-2: suboccipitalrelease alone, ccontrol group, dmean±standard deviation, eneck disability index, fdifference between pre-and post-test, significant difference in a comparison with the control group (p<.05).

Ⅳ. Consideration

the contractures of the semispinalis, which is related to the connection of the dura. And this causes headaches due to locking or instability of the joints, tension of the dura and ligaments (Melchart et al., 1999). In addition, headache may occur if there are active myofacial trigger points in the suboccipital muscles (Simons et al., 1999). Therefore, the study included subjects for chronic migraine in relation to the trigger points of suboccipital muscles, and conducted trigger-points examinations in accordance with the criteria of the prior study (Fernández, 2006). In addition, the relaxation technique to relax the trigger points of the suboccipital muscles were applied for at least 3 minutes since it is important to maintain a relaxed state of the suboccipital muscles (Barnes, 1996). Therefore, also in this study, we applied the suboccipital release for the whole 3 minutes. In the results of this study, at the point of comparison between the groups, the sensitivity of the pressure pain threshold of actual headache areas and myofascial trigger points were decreased regardless of the application of the high-frequency diathermy. And we can also confirm that the suboccipital release is effective in decreasing headache and increasing neck mobility referred by HIT-6 points. The treatment is not only helpful to release the muscles but also stimulates intracranial

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twitch and increase cerebral blood flow (Seo et al.,

2002). Thus, it’s known as effective in increasing

velocity of cerebral circulation. According to a

precedent study, the distributions of referred pain

by trigger points of head, neck and shoulders

were correspond to the trigger points of chronic

tension-headache patients (Fernández, 2007).

Patients with cervical headache had lower

thresholds for tenderness compared to healthy

subjects or other types of headache, and in

patients with tension-type headache, neck bending

was found to be less than in healthy subjects

(Bovim, 1992). Cheon (2012) reported that there

was a change in the slope of the neck due to

relaxation of the irregularly coherent or dispersed

muscles and fascia after applying the anatomy-trains

massage technique to the occipital region. Ajimsha

(2011) reported that the use of fascia relaxation

technique to tension-headache patients decreased

the headaches from the 4th week. And Monzani et

al. (2016) reported that headache pain was

reduced by applying fascia relaxation technique

to patients with tension-headache for 4 weeks,

and quality of life in workplace was improved. In

addition, Cho (2014) reported that the application

of fascia relaxation technique for 4 weeks to

patients with tension-headache suppressed

effectively the active myofascial trigger points in

the soft tissues of suboccipital region and reduced

headaches. In this study, the NDI scores were

improved significantly when combined with

high-frequency diathermy, and it may be associated

with a decrease in HIT-6 score and tenderness.

The main effects of high-frequency diathermy are

increasing microcirculation, vasodilation, and

increasing internal temperature (Ganzit, 2000). In

other words, high-frequency therapy has the

effect of activating the autonomic nervous and

the sympathetic nerve by releasing the alternating

current into the body tissue to turn it into heat

energy and releasing the muscle, ligament, and

tendon (Chung, 2006). In addition, the application

of high-frequency diathermy increases the local

temperature up to 40~45°C, which is the function

recovery temperature of the tissue, so that the

pain threshold is increased and the pain is

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reduced. Maximum stretching can be achieved

without tissue damage when the connective

tissue's local temperature is at 40~50°C (Lehmann

& De Lateur, 1990). Pernía(2009) reported that by

applying high-frequency diathermy for a period of

10 sessions(once in a day, 1session=5days) to 100

patients of degenerative neck-pain, it showed a

rapid effect on reducing pain. Jang et al. (2009)

reported that by applying 20 minutes of

high-frequency treatment and hand massage for

10 minutes for 3 weeks to nurses in university

hospitals, it reduced trapezius pain and stress.

And a decrease in pain and edema by applying

high-frequency diathermy to an athlete with ankle

sprain was reported (Melegati et al., 2003). Shim

(2008) researched by applying high-frequency

treatment to a man with stressed neck and

shoulder pain, and found that the pain decreased

so he did not appeal a headache from the second

week. Therefore, the manual therapy such as

relaxation technique is effective in reducing

referred pain associated with the trigger points of

suboccipital muscles of the tension-type headache

patients and reducing the sensitivity of the

pressure pain threshold. Furthermore, we can

consider that integrating high frequency diathermy

into the existing relaxation technique is more

effective on increasing pressure pain threshold of

headache area and soft tissues and increasing

neck mobility by applying the technique in

circumstances of changing stretching-forces of

the tissue result from increasing local temperature

of deep connective tissues, and occurring maximum

stretching status without damaging tissues. The

limitations of this study are that the number of the

subjects was rather low and we couldn’t confirm

the effect of high-frequency diathermy treatment

alone on headache since there was no group of it.

Also, all the subjects were outpatients so we could

not able to control the variables completely other

than treatment time, and their drug uses neither.

Therefore, it is seemed necessary to study about a

long-term treatment for many subjects with

various age groups in the future.

Patients with chronic tension-type headache have a pain pattern that causes headache by the active myofascial trigger points in the suboccipital muscles, and their trigger points are more sensitive than in the normal cases. Relaxation techniques have been studied to reduce the sensitivity of trigger points, which are non-pharmacologicalmethods. But there were not much interests in the effect of high-frequency diathermy integrated into relaxation techniques. This study was conducted to determine if the effects of suboccipital release can be improved in parallel with the high-frequency diathermy, and the results of this study showed

Ⅴ. Conclusion

that the suboccipital-release helps to improve the function of the head and neck, and also shows a more positive effect when combined with the high-frequency diathermy. This result implies that simultaneous application of heat therapy by using high-frequency diathermy is more effective in order to increase the effectiveness of the relaxation technique in patients with chronic tension headache. In addition, since the high-frequency diathermy is safe and easy to apply, studies should continue to verify the effects of heat therapy combined with manual therapy in the future.

Refer ences

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