Effectiveness of the muscle energy technique on respiratory muscle strength and endurance in patients with fibromyalgia

Abstract

BACKGROUND:

Fibromyalgia is characterized by a chronic and common musculoskeletal system pain that affects cervical mobility and inspiration. This may cause changes in thoracic mechanics.

OBJECTIVE:

To investigate the effectiveness of the muscle energy technique applied to cervical accessory respiratory muscles on respiratory muscle strength and endurance in patients with fibromyalgia.

METHODS:

The participants were 37 women diagnosed with fibromyalgia. They were assessed for their respiratory muscle strength, respiratory muscle endurance, pain and fatigue severity, flexibility and disability. The muscle energy technique was applied to the scalene, upper trapezius, and sternocleidomastoid muscles after a superficial heat application. The treatment was continued for 3 weeks with 3 sessions per week.

RESULTS:

After the treatment, expiratory muscle strength and respiratory muscle endurance increased significantly. Severity of pain and fatigue and disability were reduced, cervical flexibility increased significantly ( $p<$ 0.05). The effect size was $r\geqslant$ 0.4 for all the variables.

CONCLUSION:

The muscle energy technique applied to cervical accessory respiratory muscles in patients with fibromyalgia who had complaints in the neck and back region positively increased respiratory muscle strength and endurance, cervical flexibility, and decrease pain intensity, fatigue and disability. It is recommended that subsequent randomized studies are carried out with a placebo control group.

Keywords

Respiratory muscle strength respiratory muscle endurance pain intensity cervical flexibility fatigue disability

1. Background

Fibromyalgia syndrome (FMS) is characterized by a complex, chronic and common musculoskeletal system pain with an aetiology that is not quite known. Morning stiffness, sleep disturbance, fatigue, muscle stiffness, anxiety, depression, cognitive dysfunction and various somatic symptoms are frequent in FMS [1, 2]. Patients’ pain complaints are chronic, widespread and generally symmetrical with a burning, refractory, and stinging sensation. Pain tends to increase with activity and exercise [3].

Respiratory muscle strength and endurance of FMS patients are lower than those of healthy individuals in control groups [4, 5]. Chronic pain in the cervical region and psycho-pathological events such as anxiety and depression interfere with each other, leading to weakness of the muscles in that region, muscle imbalance, decreased cervical mobility, and consequent postural changes and proprioceptive sensory disturbances. The change in the length-tension relationship of muscles causes the weakening of the muscles such as scalene, trapezius and sternocleidomastoid (SCM) muscles in the cervical region. As a result, cervical mobility and inspiration are affected. All of these can cause respiratory problems by causing changes in the thoracic mechanics and decreasing respiratory muscle strength [6, 7].

It has been reported that muscle ischemia [8], inflammation and fascial dysfunction may lead to central sensitization or disinhibition changes in FMS patients, and consequently pain may increase [9]. It has been reported that the treatment applied to cope with widespread pain in FMS should include the fascia, because the pain can be reduced by the structural changes formed on the fascial matrix [10]. In this context, interest in fascial techniques for pain modulation has increased [9].

The muscle energy technique (MET) is one of the soft tissue osteopathic manipulation methods developed to improve the function of the musculoskeletal system and reduce pain, where the patient participates actively in the treatment (through isometric and/or isotonic contractions) [11]. The contractions and positions used in the treatment of MET stimulate the fascial tissue in that region and provide its mobility [12]. MET results in decreased muscle tone and sympathetic tone as well as causing localized vasodilatation by providing fascial stimulation [12, 13]. The literature review revealed that the MET treatment is generally used to reduce pain and increase joint range of motion and flexibility [14, 15, 16].

To the best of our knowledge, there is no study in the literature investigating the effect of MET treatment on the accessory respiratory muscles in the cervical region, which are shortened and have an altered length-tension relationship in FMS, and the effect of this treatment on respiratory muscle strength and endurance. This study was conducted to investigate the effect of MET treatment applied to cervical accessory respiratory muscles on respiratory muscle strength and endurance in FMS patients.

2. Methods

This study was approved by the Health Ethics Sub-Committee of the Scientific Research and Publication Committee of the Eastern Mediterranean University on March 3, 2017 and with the decision number 2017/39-12. The study was conducted between March and November 2017 as a pre-test and post-test research design. The study was carried out on 44 individuals between the ages of 25 and 60 who were diagnosed with FMS – according to the criteria of the 2010 American Rheumatism Association – at the Ga- zimağusa State Hospital, Polyclinics of Orthopaedics, Traumatology and Physical Therapy and Rehabilitation, who were referred to the Department of Physiotherapy and Rehabilitation of Eastern Mediterranean University Faculty of Health Sciences. The sample size of the study was calculated using the G Power computer program, taking into account the statistical tests to be used in the analyses and the traditional effect size values proposed by Cohen [17]. Patients with cardiopulmonary disease, thoracic deformities affecting respiration (barrel chest, scoliosis, pectus excavatum, sternal defects), other cervical musculoskeletal problems (cervical disk herniation, spinal stenosis, myofascial pain syndrome, chronic fatigue syndrome), cerebrovascular events, neuromuscular disease, cancer history, uncontrolled endocrine diseases, hypertension (systolic $>$ 140 mmHg and/or diastolic $>$ 90 mmHg), antidepressant use and those with a positive vertebrobasilar artery test were excluded from the study. Informed consent forms were obtained from all participating individuals.

The socio-demographic information of the individuals was recorded. The time since diagnosis and the duration of complaints were questioned. Respiratory muscle strength and endurance measurements were performed as the primary outcome measure. Pain severity, cervical flexibility, fatigue and disability levels were used as the secondary outcome measures. The evaluations were repeated by the same physiotherapist pre- and post-treatment.

The measurement of the respiratory muscle strength was performed using a Carefusion-MicroRPM instrument capable of measuring mouth pressure. The nose was closed with the help of a latch to prevent air ingress and egress. While the patient was sitting on a chair, maximum inspiratory pressure (the maximum air pressure value that the patient could take against the device after maximal exhalation) and maximum expiratory pressure (the maximum air pressure value that the patient could give to the device after maximal inspiration) were measured. Three measurements were made for the MEP and MIP values, and the best value of each was recorded [18].

The maximal voluntary ventilation (MVV) was measured with a Futuremed’s Discovery-2 respiratory function tester to determine the respiratory muscle endurance. The individuals were asked to breathe quickly and deeply for 12 seconds (sec) while the nose was closed with a latch and the mouthpiece was placed in the mouth in a way to prevent air leakage. This was repeated three times, and the best value was recorded [18, 19]. Approximately 1 minute (min) of resting time was provided between the measurements of respiratory muscle strength and endurance to prevent fatigue.

The pain severity experienced by the individuals in the neck and back region was assessed using the Visual Analogue Scale [20]. The distance between the suprasternal notch and the mental protuberantia was measured for cervical flexion and extension flexibility, the distance between the mastoid process and the acromion for lateral flexion flexibility, and the distance between the mental protuberantia and the acromion for rotation flexibility were measured. The measurements were made using a measuring tape. The values were recorded in centimeters (cm) [21]. Care was taken to ensure that the teeth of the patients were in contact with each other to prevent misalignment during the flexion and extension flexibility measurements.

The Turkish version of the Fatigue Severity Scale was used to determine the effect of fatigue on the functions [22]. The Turkish version of the Revised Fibromyalgia Impact Questionnaire (RFIQ) was used for the measurement on disability [23].

The treatment was given to the participants 3 days a week for a total of 3 weeks. The MET treatment was administered after 20 min of superficial heat (hot pack) application to the cervical region in each session. The individuals’ upper trapezius, scalene (anterior, medial and posterior), and SCM muscles of the neck region were subjected to the application. The maximum isometric contraction strengths were measured using a sphygmomanometer after the indicated muscles were set to the required position, and these values were recorded. Then, in the treatment, isometric contraction was applied for 7 sec using 20% of this value, followed by 30 sec stretching in a painless and limited position. The treatment was performed bilaterally on the indicated cervical muscles.

2.1 Upper trapezius

The subjects were put into a supine position, while letting them perform a slight forward head flexion, ipsilateral rotation and lateral flexion to the opposite side. The flexion was provided with a pillow under the head. The patient was asked to perform an isometric contraction of 7 sec with a force of 20% of the maximum isometric contraction force, where the restriction was felt. Then, the patient was allowed to breathe for relaxation. After relaxation, the individual was positioned on the new barrier and left there for 30 sec. The patient was brought to the normal position slowly and passively by the therapist [24] (Fig. 1).

2.2 Scalene muscles

The treatment was performed in 3 different positions. The subjects were laid in a supine position for full rotation and the lateral flexion position of the posterior scalene muscle towards the opposite shoulder, for 45 ${}^{\circ}$ rotation and full lateral flexion position of the middle scalene muscle, and for mild rotation and full lateral flexion position of the anterior scaling. The individuals were asked to hold their breath during the isometric contractions in the treatment and breathe out during relaxation [24]. Holding the breath during the treatment of the scalene muscles with MET would automatically cause isometric contraction. For this reason, its use in the treatment of these muscles is helpful [25].

2.2.1 Posterior scalene muscle

The individuals’ opposite side hands were placed on the ipsilateral 2nd costa. One hand of the physiotherapist was placed on the patient’s hand and the other hand was placed in such a way that could support the position of the patient’s head. After inspiration, the individuals were asked to perform isometric contraction for 7 sec in the opposite direction of the movement and then relax with expiration. Meanwhile, the physiotherapist supported the expiration by helping the movement of thorax obliquely with the hand on the patient’s hand. Then, passively, the neck was brought to a new barrier, and it was left there for 30 sec [24] (Fig. 2).

2.2.2 Middle scalene muscle

The head of the individual was positioned as described above, the hand was placed under the 2nd costa towards the centre of the clavicle, and the same procedure was repeated (Fig. 3).

2.2.3 Anterior scalene muscle

After positioning the head in the position described above, the intervention was performed by placing the individuals’ hands on the sternum [24] (Fig. 4).

2.3 Sternocleidomastoid muscles

The individuals were laid in a supine position so that their heads would be at an extension of 10–15 ${}^{\circ}$ . The hand on the opposite side of the involved muscle was placed on the sternum. The neck was positioned at a painless and maximum contralateral rotation position. While in this position, the patient was asked to lift their head slightly towards the ceiling and hold their breath. The resistance needed in this position was not provided because the gravity would provide it. After 7 sec of contraction, the physiotherapist assisted in the expiration by applying stretching from the sternum obliquely with one hand at the same time as the patient was exhaling. The patient’s head was supported from underneath with the other hand. Then, the head was brought to a new barrier and left for 30 sec in this position [24] (Fig. 5).

2.4 Statistical analysis

The data obtained from the study were analysed using the PASW Statistics 18 Release 18.0.0 software. Non-parametric statistical tests were used for the statistical analyses, as the Shapiro-Wilk test showed that the data did not fit normal distribution. The Wilcoxon Sign Test was used to compare the pre- and post-treatment measurements. Descriptive statistics for the discrete and continuous variables in the study were expressed in percentages, means $\pm$ standard deviations and counts. A value of $p<$ 0.05 was accepted to be the statistically significant rate. The 95% confidence interval (95% CI) values were also given along with the arithmetic means. The “ $p$ ” values and “95% CI” values were used to interpret whether the pre-treatment and post-treatment measurements were significantly different from each other [26]. The effect size was calculated to determine the clinical effectiveness of the treatment. The calculations were made using the formula “ $r=z/\surd(n\times 2)$ .” An effect size of “ $r\leqslant$ 0.1” was interpreted as a small effect, “ $r=$ 0.3” was considered as a medium effect, and “ $r\geqslant$ 0.5” was accepted as a large effect [27].

3. Results

A total of 44 female patients diagnosed with FMS participated in the study. Seven patients were excluded from the study because of unavailability, other health problems or because they could not get permission from their workplaces (Fig. 6). The remaining 37 individuals with FMS had a mean age of 40.5 $\pm$ 8.7 years. The socio-demographic information of the individuals is shown in Table 1.

Table 1

Socio-demographic characteristics of the subjects, ( $n=$ 37), (95% CI)

Variables	Statistic	95% Confidence
		interval
Age, year, (x $\pm$ sd)	40.5 $\pm$ 8.7	(37.6	–43.4)
BMI, kg/m ${}^{2}$ , (x $\pm$ sd)	25.2 $\pm$ 4.5	(23.7	–26.7)
Sex, $n$ (%)
Female	37 (100.0)	(0.9	–1)
Male	0	(0	–0.1)
Marital status, $n$ (%)
Married	28 (75.7)	(0.6	–0.9)
Single	9 (24.3)	(0.1	–0.4)
Education status, $n$ (%)
Primary school	11 (29.7)	(0.2	–0.5)
Middle school	4 (10.8)	(0	–0.2)
High school	9 (24.3)	(0.1	–0.4)
University	7 (18.9)	(0.1	–0.3)
Master-doctorate	6 (16.2)	(0.1	–0.3)
Duration of illness (month)	18.4 $\pm$ 43.4	(3.9	–32.9)
Duration of complaints	73.3 $\pm$ 80.2	(46.6	–100)
(month)
Simple analgesic use, $n$ (%)
Yes	13 (35.1)	(0.2	–0.5)
No	24 (64.9)	(0.5	–0.8)

BMI: Body Mass Index, n: number of subjects, sd: standard deviation.

The MEP, MIP and MVV values of the primary outcome measures were significantly different after the treatment in comparison to those before the treatment (all $p<$ 0.001). On the contrary, it was determined that there was an overlap in the upper and lower boundaries of the 95% CI belonging to the MEP value, and the 95% CI of the mean difference covered the value “0”. For these variables that were examined, the effect sizes were calculated as $r\geqslant$ 0.4 (Table 2).

Table 2

Comparison of respiratory muscle strength and endurance values of subjects before and after treatment, $x$ $\pm$ sd, (95% CI)

Variables	Pre-treatment ( $n=$ 37)	Post-treatment ( $n=$ 37)	$p^{*}$	CI difference	Effect
				of 2 means	size
Respiratory muscle strength
Maximal inspiratory pressure, (cmH ${}_{2}$ O)	69.1 $\pm$ 19.8 (62.5–75.7)	75.5 $\pm$ 19.3 (69.1–81.9)	0.000	( $-$ 15.5–2.7)	0.4
Maximal expiratory pressure, (cmH ${}_{2}$ O)	77.6 $\pm$ 17.5 (71.8–83.4)	86.7 $\pm$ 20.2 (80.0–93.4)	0.000	( $-$ 17.9– $-$ 0.3)	0.4
Respiratory muscle endurance
Maximal voluntary ventilation, (%)	64.7 $\pm$ 11.9 (60.7–68.7)	73.7 $\pm$ 13.2 (69.3–78.1)	0.000	( $-$ 14.8– $-$ 3.2)	0.4

${}^{*}$ : Wilcoxon sign rank test, CI: Confidence interval.

While the individuals’ pain severity, fatigue severity and disability scores in the cervical region were reduced significantly post-treatment in comparison to pre-treatment, and the cervical flexibility was found to be significantly increased (all $p<$ 0.05). The clinical effect sizes for all these variables except for the function sub-scale of RFIQ were calculated as large (all $r\geqslant$ 0.5), and $r=$ 0.4 for the function sub-scale score (Tables 3 and 4).

Table 3

Comparison of pain severity and cervical flexibility values of subjects before and after treatment, $x$ $\pm$ sd, (95% CI)

Variables (cm)	Pre-treatment ( $n=$ 37)	Post-treatment ( $n=$ 37)	CI difference of 2 means	Effect size
VAS	6.6 $\pm$ 1.5 (6.1–7.1)	2.1 $\pm$ 1.9 (1.4–2.6)	(3.71–5.29)	0.6
Flexion	2.9 $\pm$ 1.1 (2.5–3.3)	2.2 $\pm$ 1.0 (1.9–2.5)	(0.2–1.2)	0.5
Extension	17.3 $\pm$ 1.9 (16.7–17.9)	18.2 $\pm$ 1.6 (17.7–18.7)	( $-$ 1.7– $-$ 0.1)	0.5
Right lateral bending	13.2 $\pm$ 1.5 (12.7–13.7)	12.1 $\pm$ 1.5 (11.6–12.6)	(0.4–1.8)	0.5
Left lateral bending	13.0 $\pm$ 1.4 (12.5–13.5)	11.9 $\pm$ 1.5 (11.4–12.4)	(0.4–1.8)	0.6
Right rotation	12.1 $\pm$ 1.9 (11.5–12.7)	10.8 $\pm$ 1.6 (10.3–11.3)	(0.5–2.1)	0.6
Left rotation	12.1 $\pm$ 1.7 (11.5–12.7)	11.1 $\pm$ 1.5 (10.6–11.6)	(0.3–1.7)	0.5

${}^{*}$ : Wilcoxon sign rank test, CI: Confidence interval, cm: centimeters.

Table 4

Comparison of fatique severity scale and revised fibromyalgia impact questionnaire values of subjects before and after treatment, $x$ $\pm$ sd, (95% CI)

Variables	Pre-treatment ( $n=$ 37)		Post-treatment ( $n=$ 37)		CI difference of 2 means	Effect size
FSS score	5.1	$\pm$ 1.0 (4.8–5.4)	4.4	$\pm$ 1.3 (4.0–4.8)	(0.2–1.2)	0.5
RFIQ total score	51.4	$\pm$ 12.9 (47.1–55.7)	30.4	$\pm$ 13.6 (25.9–34.9)	(14.9–27.1)	0.6
RFIQ function score	12.6	$\pm$ 6.7 (10.4–14.8)	8.3	$\pm$ 5.0 (6.6–10.0)	(1.6–7.0)	0.4
RFIQ overall impact score	10.8	$\pm$ 4.5 (9.3–12.3)	5.4	$\pm$ 3.4 (4.3–6.5)	(3.6–7.3)	0.6
RFIQ symptoms score	27.9	$\pm$ 6.5 (25.7–30.1)	16.7	$\pm$ 7.9 (14.1–19.3)	(7.9–14.6)	0.6

${}^{*}$ : Wilcoxon sign rank test, CI: Confidence interval, FSS: Fatigue severity scale, RFIQ: Revised fibromyalgia impact questionnaire.

4. Discussion

We investigated the effectiveness of MET applied to the accessory respiratory muscles in FMS patients. We found that the combination of superficial heat applied to the neck region and the MET treatment improved respiratory muscle strength, respiratory muscle endurance and Moreover, it was also emphasised that incorrect diagnoses may be prevented by the pain of the SCM and upper trapezoid muscles trigger points that spreads in the face MET treatment involves contraction, relaxation and subsequent passive stretching of the patient against the power of the clinician at the target musculotendinous unit [12]. Fascia is the richest sensory organ in our bodies which surrounds the whole body [28]. It has the ability to contract like a smooth muscle, and this characteristic of it affects musculoskeletal dynamics. The density of innervation of the mechanoreceptors in the fascia directly connects the fascia to the central nervous system. Any interference that affects the fascia actually affects the autonomic nervous system as well. Most nerve endings in the fascia are receptors that can be stimulated by fascial manipulation and cause local vasodilatation [13].

Cervical mobility is increased as a result of fascial heat treatment applied before MET, which is one of the fascial techniques applied to the neck region in FMS patients. This corrects the head posture and the length-tension relationship of muscles. It may thus have contributed to the formation of cervical local and global muscular balance and segmental stabilization as well as healing in functions [29, 30].

The increase in cervical muscular balance and stability may have affected the functions of the thoracic cage and the costal cage mechanics. Garland described (cited in Chaitow, 2006 [11]) somatic changes following upper chest respiration and hyperventilation. Accordingly, as a result of persistent upper chest breathing, a reduced diaphragmatic activity and lower rib cage constraints (including inappropriate and excessive use of accessory respiratory muscles) arose. It was reported that persistent upper chest breathing will lead to visceral stasis and pelvic floor weakness. A muscle imbalance develops between the increasingly shortened erector spinae and weakened abdominals. It was stated that there will be a fascial restriction from the central tendon of the diaphragm to the occipital base through the pericardial fascia, the upper costa will rise, and sensitive costal cartilage tension will develop. Because of the limitations of the costal joints, the thoracic spinae will also be affected. Accessory muscle hypertonus, especially in the scalene muscles, the upper trapezius and the levator scapulae will be made visible and palpable by this. It was stated that this will set the stage for the development of sensitive spots in the muscles and for the development of myofascial trigger points, and the cervical spine will become stiffer. Disorders in the respiratory pattern will cause loss of functional tone of the diaphragm and other core stabilization muscles such as the transversus abdominis [31]. Based on this information, it may be considered that the values of MEP and MIP are affected in patients with FMS, and somatic changes provided by the combination of superficial heat and MET treatment may increase the values of MEP and MIP. Additionally, the significant decrease after treatment in the symptom sub-scale score of the RFIQ, which includes anxiety and depression questions, and the relaxation of the cervical muscles and fascia might have positively affected the costal mechanics [6]. All of these are thought to be the possible underlying causes of increased respiratory muscle strength. In addition to the previous study which showed that intervention on chronic obstructive pulmonary disease patients has shown soft tissue techniques which includes that MET increased lung function. The previous study reported that an improvement was obtained in lung functions in chronic obstructive pulmonary disease patients in the implementation of soft tissue manual therapy including MET that is applied on accessory respiratory muscles [32].

FMS patients have lower respiratory muscle endurance than healthy individuals in control groups. Endurance capacity is closely related to the mechanical properties of the lung, chest wall and respiratory muscles (muscle type, appropriate blood flow, muscle contractile characteristics, etc.) [33]. Additionally, the intensity of the mitochondrial volume in the muscle is directly related to endurance capacity [34]. In our study, it was observed that the MET treatment applied to the patients’ accessory respiratory muscles after the treatment provided significant increases in respiratory endurance. This result may have been due to the success of the patients’ relaxed, deep and rapid breathing that resulted from a decrease in pain in the neck region, an increase in respiratory muscle strength and relaxation of SCM, scalene and upper trapezius muscles. In other words, the relaxed muscles may have been able to work more actively during the MVV test, revealing the patient’s maximum capacity.

In our study, there was a significant reduction in the pain felt by the patients in the neck region, and the clinical effect was large. Among the mechanisms of the MET treatment that reduced pain, it is possible to account for the fact that it improved the tolerance against stretching and reduced pain sensation by stimulating the muscle and the joint mechanoreceptors [35]. The contribution of the applied superficial heat in reduction of the pain cannot be neglected. Superficial heat stops the delivery of pain to upper centres, increases the pain threshold, and increases enkephalin and endorphin release. It reduces the mechanical factors such as the change in the viscoelastic properties of the tissue, and therefore, the pressure and tension at the nerve endings. It also increases vasodilatation. All of these are the basic mechanisms that play a role in pain modulation.

Magnusson et al. reported that isometric contraction and stretching used in MET treatment reduced pain sensation and increased tolerance against stretching by stimulating the mechanoreceptors in muscles and joints [35]. Feland and Marin designed a study to investigate the effects of contraction force on flexibility in the contract-relax technique, one of the proprioceptive neuromuscular facilitation techniques. They had individuals perform contractions at values of 20%, 60% and 100% of the maximal voluntary contraction and then applied stretching. No treatment was administered to the control group. As a result, the 20% and 60% rates of the maximal voluntary contractions were found to be as effective as 100% contractions for hamstring flexibility. The authors stated that the maximum contractions may cause injuries and stressed that they should be handled as side effects [36]. It was reported in the literature that pain relief, flexibility and increased range of motion are associated with the treatment of MET, which is applied to the cervical region [14, 37, 38, 39, 40]. The MET treatment, which was administered at a value of 20% of the maximum voluntary contraction with superficial heat significantly increased neck flexibility in our study as well.

One of the main symptoms of FMS is fatigue. In the literature, there is no consensus on the recurrence of MET treatment in FMS patients. Additionally, no information was available about the dosing parameters of the MET treatment applied to the accessory respiratory muscles. For this reason, the MET treatment was applied with one repetition in our study, with the thought that it might increase fatigue. In our study, as a result of the MET treatment, it was determined that the FMS patients who felt intense pain in the neck area felt a relief in fatigue severity, which is the most important symptom of the disease. The reduction in fatigue severity may also be the result of physiological effects such as changes in the biomechanical effects of the MET treatment and in the muscle metabolism in the patients. The improvement in the psychological symptoms seen in the FMS patients and the increase in the energy level paralleling that may also have contributed to the reduction of fatigue severity. However, the detailed evaluation of the psychopathological level will shed more light on the subject.

After the MET treatment, the level of disability in the FMS patients was significantly reduced. In our study, we used RFIQ, which is recommended to be used to determine the disability level of FMS patients. The “function”, “general”, and “symptom” sub-scales of RFIQ decreased, and there was a reduction in the total scores of RFIQ. The decreases in physical and psychological symptoms such as pain, sleep disturbances, depression, anxiety, photophobia, phonophobia and morning stiffness – and ultimately, the increase in the function – may explain the decline in disability.

The positive effects of MET have been demonstrated when it was applied in combination with other manual techniques, too. However, determining its primary effects in such studies may have been limited. In patients with trigger points in their upper trapezoid muscles, it was shown that there are positive effects on pain severity when MET treatment is applied with other neuromuscular inhibition techniques. The same effect was not found on the pain threshold [41]. In patients who were administered soft tissue relaxation, exercise and MET who had non-specific neck pain, it was reported that the movement range in the joints increased and the pain and disability decreased [42]. It was reported that there was a decrease in the symptoms in Bell’s palsy treatment when MET and SCM were applied in addition to acupuncture, physiotherapy and medical treatment. It was reported that peripheral blood flow increases and the hyperactivation of the sympathetic nervous system decreases by the relaxation of the SCM muscle. Moreover, it was also emphasised that incorrect diagnoses may be prevented by the pain of the SCM and upper trapezoid muscles trigger points that spreads in the face [43].

Osteopathic manipulative approaches involving MET are encountered in patients with fibromyalgia [44]. However, this study is the first study to apply the MET treatment to the cervical accessory respiratory muscles in FMS patients, and it is expected to contribute to the literature. The most important limitation of our study was the lack of a control group. Another limitation was that the outcome measures were not carried out at the same time of the day, because the circadian rhythm can directly affect autonomic symptoms [45]. The fact that the number of patients who were admitted to the Gazimağusa State Hospital and received FMS diagnosis was inadequate was the main cause of our limitations.

In conclusion, the superficial heat and MET treatment applied to the cervical accessory respiratory muscles in the FMS patients who had complaints in the neck and back region were found to be an effective method to increase respiratory muscle strength and endurance, cervical flexibility and decrease pain intensity, fatigue and disability levels. It will be possible to conduct randomized placebo-controlled studies on patients with FMS in the future and reach an evidence-based conclusion. Moreover, there is a need for electrophysiological studies in order to elucidate the underlying mechanisms of the obtained changes. When it is considered that FMS is a disease characterized by widespread pain, an application of the MET treatment to other body regions may provide important contributions to the literature. Considering the increase in respiratory muscle strength and endurance, it is also believed that respiratory functions might increase. For this reason, it is recommended to study the effect of MET – applied to accessory respiratory muscles – on respiratory functions in future studies.

Footnotes

Conflict of interest

None to report.

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