EFFECT OF DYNAMIC STABILIZATION EXERCISE ON ELECTROMYOGRAPHIC ACTIVITY OF MULTIFIDUS IN CHRONIC LOW BACK PAIN PATIENTS

EFFECT OF DYNAMIC STABILIZATION EXERCISE ON ELECTROMYOGRAPHIC ACTIVITY OF MULTIFIDUS IN CHRONIC LOW BACK PAIN PATIENTS

Mohamed H.Rashad* ;Abdallah G.Ayed **

andSamah S.Zahran ***

* Lecturer in Department of Neurology, Faculty of Medicine, El Azhar University

**Demonstrator of Physical Therapy for Musculoskeletal Disorders and their Surgeries, faculty of Physical Therapy, MTI University. 

*** Lecturer of Physical Therapy for Musculoskeletal Disorders and their Surgeries, Faculty of Physical Therapy, Cairo University;

Key Words: Dynamic stabilization exercise – multifidus – SEMG – chronic low back pain

ABSTRACT

Background:  Dynamic stabilization exercise (Vojta) is a neurophysiological method used to obtain reflex responses in muscles following stimulation of particular activation zones. Objectives: To determine the effect of dynamic stabilization exercise  onelectromyographic activity of multifidus in chronic low back pain patients. Methods: thirty- five patients with chronic low back pain included in the study from MTI university outpatient clinic. Their mean ±   SD age, weight, height, and BMI were 27.25 ± 6.62 years, 80.42 ± 9.78 kg, 174.25± 3.86 cm, 26.45 ± 2.86 (kg/m²). Results:  there was a significant decrease in the EMG amplitude of multifidus in Vojta method compared with that of the maximum voluntary contraction. Conclusion: Vojta method increased the activity of multifidus muscle, but lower than the maximum voluntary contraction of multifidus.

INTRODUCTION

LBP (LBP) is a common complaint worldwide, though some people are able to deal with their LBP, for many the pain can become unbearable and debilitating. An estimated 80% of the population will suffer from LBP throughout their lifetime, this fact makes LBP the most common cause of disability in a patient younger than 45 years old( Retal, 2006). Most cases experience a chronic (>3 months) course (Hoy et al., 2010, Marienke et al., 2011 )and the pain results in activity limitation and work absence (Thelin et al., 2008).

There are various factors associated with chronic LBP, changes in motor control and muscular recruitments have been the main concern of chronic LBP treatments within the past decade (Silfies et al., 2005; Kahlaee et al., 2016).

Motor control of deep trunk muscles is altered in chronic LBP. Specifically, the lumbar multifidus (MF) anticipatory activation is delayed during rapid focal limb movement along with maladaptiveplasticity of the primary motor cortex. Such negative changes could be normalized by training the voluntary activation of deep MF, an exercise often used in physiotherapy (Hugo et al., 2015).   

It is claimed that there is a link between local muscle dysfunction and LBP, with the development of clinical instability in which there is an excessive range of abnormal segmental movement without muscular control (Richardson et al., 1999).  Several studies have shown that subjects suffering from LBP frequently show persistent involvement of the lumbar MF muscle, For example, atrophy, and fatty infiltration have been reported (Knutsson, 1961; Alaranta et al., 1993; Money et al., 1997; Donneels et al., 2000; Hides, 2008; Wallwork et al., 2009; Paolo et al., 2015). Reduced activity has been demonstrated in persistent LBP (Sihvonen et al., 1997; MacDonald et al., 2008, 2010), and fiber transformation from type I to type IIC has also been observed (McGill 1998; Mannion et al., 1997; Demoulin et al., 2007; Crossman et al., 2004).

Recovery of MF muscle activation and endurance is considered essential for restoring the proper function of the lumbar muscle “core” (O’Sullivan 2000; Zhay et al., 2014; Miura 2014 ). There are different available methods to assess muscle characteristics and morphologies including Electromyography (EMG) (Beith et al., 2001; Brown and McGill 2010; ), Magnetic Resonance Imaging (MRI) (Hides et al., 2006; 2007; 2010) and Sonography (Whittaker 2008; Langevin et al., 2009; Ghamkhar et al., 2011, Pulkovski et al., 2012).

The ability to activate the lumbar MF muscle was identified as a predictor of clinical success with a spinal stabilization exercise program (Hebert et al., 2010). Consequently, clinicians routinely include muscle activation training specific to the lumbar MF muscle in spinal stabilization exercise programs for treating patients with LBP (Hicks et al., 2005; O’Sullivan et al., 1997).

Dynamic stabilization exercise is a neurophysiological method used to obtain reflex responses in muscles following stimulation of particular activation zones(Ewa et al., 2017).Vojta reflex locomotion has been reported to activate the trunk muscles and the deep muscles of the spine that regulate trunk stability and increase spinal rotation force, thereby enhancing postural control ability (Son, 2000). The basic principle of Vojta reflex locomotion is the maintenance of postures through isometric contraction of muscles during point stimulation, thereby ensuring constant patterns of muscle contraction and leading to the stimulation of muscles, joints, ligaments, and tendons. In addition, Vojta reflex locomotion is known to be related to the exteroceptors and the enteroceptors and to become a source of afferent stimulation going into the central nervous system (Vojta, 1977).

Sun and Yun (2016) found that Vojta method with stimulation of the breast zone augments activation of the transversusabdominismuscle  (TrA) and the diaphragm, and inhibits the activation of the external obliques muscle in normal adults.

Methods

Thirty -five subjects (male and female) complaining of chronic non -specific low back pain will be recruited to share in this study. Sample size calculation was performed using G*POWER statistical software (version 3.1.9.2; Franz Faul, Universitȁt Kiel, Germany) (Faul et al, 2009) and revealed that the appropriate sample size for this study was N=35 which gave observed power equal to 0.8. Calculations were made using α=0. 05, β=0.2 and an effect size of 0.5.  All subjects will read and sign a consent form prior to the beginning of testing for ethical issues. Subjects will be recruited based on the following inclusion and exclusion criteria:

Inclusion Criteria

• Patients with chronic (more than 3 months) non-specific low back pain aged >18years old (Marienke et al,2011).
• BMI will be less than 30 kg/ m2, as the amplitude, time and frequency domain properties of the SEMG signal are affected by the thickness of overlying skin and adipose tissue. The more
• Superficial the muscle and the lesser the amount of subcutaneous adipose, the greater will be the SEMG amplitude (Gerdle et al., 1999).

Exclusion Criteria

Patients with previous spinal surgery

• Patients who have signs and symptoms of gross spinal instability.
• Patients who have a radiological diagnosis of spondylolysis or spondylolisthesis.
• patient with any neurological diseases

Instrumentations and procedures:

Surface Electromyography (SEMG)

To assess muscular activation patterns in musculoskeletal disorders by measuring the amplitude of muscle activity (Lehman et al., 2004; Lewis et al., 2009).

Nihon KohdenNeuropack

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Procedures for measuring  muscles activity

Participant’s position and electrode placement:

EMG activity of the lumbar multifidus muscles will be recorded following a testing protocol published in previous studies by (Kiesel et al  2007).

Briefly, each participant will be instructed to lie prone on an examination table with the participant’s shoulders abducted, elbows flexed approximately 80-90°, and the forearms hanging off the edge of the table.       To prepare for EMG recording, each participant’s skin over the right and left lumbar multifidus muscles at L5 will be cleaned with alcohol and, if needed, excessive hair will be shaved using a disposable razor. Adhesive tape will be used to affix two EMG electrodes to the skin over the bilateral lumbar multifidus muscles. Following the recommendation by the Surface Electromyography for the Non-Invasive Assessment of Muscles (SENIAM) project (http://www.seniam.org/), two surface electrodes will be placed at the level of the L5 spinous process about 2 - 3 cm from the midline and will be aligned with a line from the posterior superior iliac spine to the interspace between the L1 and L2 spinous process. Two trials of maximal voluntary isometric contraction (MVIC) of the lumbar multifidus muscles will be obtained by asking the participant to perform a bilateral arm lift from the resting position and to lift their chest off the table while the investigator applied a steady downward force on the elbow opposite the side of the tested lumbar multifidus muscle. Two 5-second MVIC trials will be recorded for the right and left lumbar multifidus muscles, respectively (Sharon et al., 2017) (fig. 7). Then SEMG recordings will be performed during stimulation at certain zones according to the Vojta methodology. SEMG will be bilaterally recorded from MF muscles following pressure–like stimulation of the calcaneus and anterior superior iliac spine (ASIS) (Elena, 2013).

Postural positions and movement trigger zones according to Vojta:

Pressure-like stimulation of the calcaneus and ASIS will be performed in the postural position named by Vojta as “reflex creeping”. The subject will be in the prone position, with the head turned at 30 degrees and supported on the frontal eminence, which will be accompanied by a passive extension of the cervical spine. The upper extremity on the facial side will be flexed in the glenohumeral joint at the angle exceeding 120 degrees, but less than 135 degrees (Ewa et al., 2017).

The arm will be abducted to 30 degrees. The elbow joint will be flexed at the angle of 45 degrees. In this way, the medial epicondyle of the humerus will be lying on the ground and it constituted a support point. The forearm plane at the palmar side will be in contact with the ground. In the starting position for reflex creeping, the longitudinal axis of the arm targeted the apex of the thoracic kyphosis (Ewa et al., 2017).

The upper extremity at the occipital side lays freely along the trunk. Hand and finger joints will be positioned freely as well. The lower extremity on the occipital side will be flexed at the hip and knee joints (it will be supported on the medial femoral epicondyle) with the lower extremity on the facial side lying straight on the ground (Ewa et al., 2017).

DATA ANALYSIS:

Descriptive statistics in form of mean, standard deviation, minimum, maximum and range values were conducted for the subject's characteristics. The paired t-test was carried out for comparison of EMG amplitude of multifidus between Vojta method and MVIC. The level of significance was set at p < 0 .05. All statistical analysis was conducted through the statistical package for social studies (SPSS) version 19 for Windows (IBM SPSS, Chicago, IL, USA).

RESULTS

Subject characteristics:

Table 1 showed the subject characteristics of the study group.

Table 1.Subject characteristics.

, Mean; SD, standard deviation

- Comparison of EMG amplitude of multifidus between Vojta method and MVIC:

There was a significant decrease in the EMG amplitude of multifidus in Vojta method compared with that of the MVIC (p < 0.001). (table 2, figure 1).

Table 2. Comparison of EMG amplitude of multifidus between Vojta method and MVIC:

, Mean; SD, standard deviation; MD, Mean difference; p-value, level of significance; * Significant.

Figure (1): Mean EMG amplitude of multifidus of Vojta method and MVIC.

DISCUSSION

This study was conducted to investigate the effect of Vojta method on electromyographic activity of multifidus muscle on chronic low back pain patients. The results of the present study showed that there was a significantincrease in EMG amplitude of multifidus during Vojta method and these changes were significantly decreased than maximum voluntary contraction. the results of our study explained by the results of ( son,2000)Vojta reflex locomotion has been reported to activate the trunk muscles and the deep muscles of the spine that regulate trunk stability and increase spinal rotation force, thereby enhancing postural control ability.     Sun and Yun (2016) found that Vojta method with stimulation of the breast zone augments activation of the transversusabdominismuscle  (TrA) and the diaphragm, and inhibits the activation of the external obliques muscle in normal adults. (Ewa et al, 2017)confirmed the activity of the upper and lower extremity muscles at about 60% of maximal contraction when Vojta stimulation was applied.

Richardson et al. (1999) reported that after the abdominal hollowing exercise was applied to patients with low back pain, the activity of the rectus abdominis(RA) and external obliques (EO)  decreased, while the muscle activity of the internal obliques (IO)  and transverse abdominis (TA)   increased. Henry and Westervelt (2005) proposed that the abdominal hollowing exercise might help patients with musculoskeletal problems such as low back pain because it can induce selective contraction of the local muscles. As previously mentioned, we suggest that stimulation of the breast zone also provokes the selective contraction of local muscles, especially the multifidus muscles, to affect trunk stability.

CONCLUSION

Vojta method produces a significant increase in  EMG activity of multifidus muscle compared with resting position and we confirmed the activity of multifidus muscles at about 50% of maximal contraction when Vojta stimulation was applied.

Recommendation

A similar study should be conducted on a large number of patients to provide a wide representation of the population. Further studies should be done for using other methods of assessment of multifidus.  Similar studies should be conducted on more female patients.

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تأثیر ممارسة الاستقرار الدینامیکیعلى رسم العضلات العدیدة الشقوق فی مرضى الم اسفل  الظهر المزمن

محمد حامد رشاد * ، عبدالله جمیل عاید ** ، سماح سعد زهران ***

* مدرس بقسم الامراض العصبیه کلیه الطب جامعه الازهر

**   معید العلاج الطبیعی لاضطرابات الجهاز العضلى الحرکى وجراحته ، کلیة العلاج الطبیعی  الجامعه الحدیثه .

*** مدرس العلاج الطبیعی لاضطرابات الجهاز العضلى الحرکى وجراحته ، کلیة العلاج الطبیعی ، جامعة القاهرة.

نبذه مختصره

خلفیه : ممارسه الاستقرار الدینامیکی هی عباره عن طریقه فسیولوجیه عصبیه تستخدم للحصول على استجابه انعکاسیه  من العضلات بعد تنبیه بعض المناطق المحفزه .

الهدف : تحدید تاثیر ممارسه الاستقرار الدینامیکی علی رسم العضلات العدیده الشقوق فی مرضى الالام اسفل الظهر المزمن . 35 شخص یعانون من الالام اسفل الظهر المزمن   تم ضمهم من العیاده الخارجه بالجامعه الحدیثه  . بلغ متوسط ​​العمروالوزنوالطولومؤشرکتلةالجسمالمتوسطة 27.25  ±6.63سنه ‘ 80.42± 9.78 کجم ‘174.25± 3.86سم  ‘26.45± 2.86 کجم /  متر مربع.

النتائج :هناک نقص فی رسم العضلات العدیده الشقوق مقارنه بأقصى قوه انقباض للعضلات.

الخلاصه : طریقه فویتا تسببت فی زیاده رسم العضلات العدیده الشقوق ولکنها لازالت اقل من اقصى قوه انقباض للعضلات العدیده الشقوق .

الکلمات الداله :ممارسه الاستقرار الدینامیکی – العضلات العدیده الشقوق – رسم العضلات – الالام اسفل الظهر المزمن