Low Back Pain
Conditions
Keywords
Transcranial direct current stimulation, Neuromuscular electrical stimulation, Motor control exercise, Isometric exercise, Motor unit behavior, Movement control, Lumbar multifidus muscle
Brief summary
This study aims to determine the effect of different stimulations including 1) transcranial direct current stimulation (tDCS), 2) neuromuscular electrical stimulation (NMES), 3) motor control exercise (MCE), and 4) isometric exercise (IE) on movement control and motor unit behavior in individuals with movement control impairment, and determine the correlation between movement control and motor unit behavior.
Detailed description
After obtaining the written informed consent, all participants will fill out the information sheet for demographic data. Data collection will be conducted in private laboratory with closed environment. Only lab staffs can access to the lab. Female researchers will perform participant preparation. Participants will be informed that they have to change their cloth to lab tank top to expose their lower back area. However, they can decline to change their cloth. In this case, researchers will fold their cloth to expose the lower back. The body landmarks will be identified. These landmarks include 1) spinous processes (L1 and S1 levels), 2) lumbar multifidus (LM) (2 cm lateral to lower half of L4 spinous process), 3) bilateral lateral epicondyle of femur, and 4) bilateral lateral malleolus. Spinous process of L1, S2, bilateral lateral epicondyle of femur, and bilateral lateral malleolus will be used as locations for inertial measurement unit (IMU) sensors, while LM location will be used to place surface electrode for decomposition electromyography (dEMG). This preparation process will take about 20 minutes. The participant will be asked to perform 1-minute active forward bend based on speed and load that can differentiate between healthy individuals and individuals with movement control impairment. IMU and dEMG data are concurrently collected. Five-minute rest will be provided to avoid muscle fatigue. After that, participant will be randomly assigned to one of four stimulations including transcranial direct current stimulation (tDCS), neuromuscular electrical stimulation (NMES), isometric exercise (IE), and motor control exercise (MCE). Each stimulation will take approximately 20 minutes. Types of stimulation Transcranial direct current stimulation (tDCS): The participant will receive the tDCS using 5X7 cm electrodes. The anodal electrode will be placed on M1 representing the back muscles (1 cm anterior and 4 cm lateral to the vertex), while cathodal electrode will be placed on contralateral supraorbital area. The intensity will be set at 2 mA with 10-second fade in/out. The subject will be stimulated by tDCS for 20 minutes. Neuromuscular electrical stimulation (NMES): The participants will receive the NMES using interferential mode (6000 Hz, beat frequency 20-50 Hz, scanning effect) on bilateral LM. The intensity will be set at the subject's maximum tolerance. Stimulation will be set at 10 seconds on and 60 seconds off to minimize muscle fatigue. The total NMES time is 20 minutes. Isometric exercise (IE): The participant will be instructed to perform isometric back extension exercise in modified Sorensen position. The participant will hold 60 seconds in neutral position for 5 repetitions with 3 minutes rest between repetitions. Movement control exercise (MCE): The participant will be instructed to perform co-contraction of transverse abdominis and lumbar multifidus muscle, while performing self-selected pace forward bend. Emphasis will be given to move in control manner (smooth and symmetrical movement). The participant will perform 4 minutes of continuous movement for 4 sets with 1 minute rest between sets. This exercise is low intensity focusing on control of movement; therefore, the occurrence of muscle fatigue is unlikely. After completion of one session stimulation, the participant will be asked to perform 1-minute active forward bend with the same speed and load again, while IMU and dEMG data will be simultaneously corrected. IMU data will be used to determine the effect of stimulation (tDCS, NMES, IE, and MCE) on movement control in individuals with movement control impairment. dEMG data will be used to determine the effect of each stimulation on motor unit behavior (spatial and temporal motor unit recruitment). In addition, IMU and dEMG data will be further used to determine the association between movement control and motor unit behavior. Data collection including 20-minute stimulation will take approximately 30 minutes.
Interventions
DEVICETranscranial direct current stimulation
The subject will receive the tDCS using 5X7 cm electrodes. The anodal electrode will be placed on M1 representing the back muscles (1 cm anterior and 4 cm lateral to the vertex), while cathodal electrode will be placed on contralateral supraorbital area. The intensity will be set at 2 mA with 10-second fade in/out. The subject will be stimulated by tDCS for 20 minutes
DEVICENeuromuscular electrical stimulation
The participants will receive the NMES using interferential mode (6000 Hz, beat frequency 20-50 Hz, scanning effect) on bilateral LM. The intensity will be set at the subject's maximum tolerance. Stimulation will be set at 10 seconds on and 60 seconds off to minimize muscle fatigue. The total NMES time is 20 minutes.
The participant will be instructed to perform co-contraction of transverse abdominis and lumbar multifidus muscle, while performing self-selected pace forward bend. Emphasis will be given to move in control manner (smooth and symmetrical movement). The participant will perform 4 minutes of continuous movement for 4 sets with 1 minute rest between sets.
OTHERIsometric exercise
The participant will be instructed to perform isometric back extension exercise in modified Sorensen position. The participant will hold 60 seconds in neutral position for 5 repetitions with 3 minutes rest between repetitions.
Sponsors
Mahidol University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
1. Between the ages of 18 and 40 2. Both male and female 3. Presence of movement control impairment (instability catch during clinical observation of active forward bend test) 4. No current episode of low back pain 5. No definitive neurologic signs including weakness or numbness in the lower extremity 6. No previous spinal surgery 7. Have not been diagnosed osteoporosis, severe spinal stenosis, inflammatory joint disease, and/or systemic disease 8. Body mass index (BMI) less than 30 kg/m2
Exclusion criteria
1. Pregnancy 2. Any lower extremity condition that would potentially alter trunk movement in standing 3. Vestibular dysfunction 4. Extreme psychosocial involvement 5. Active treatment of another medical illness that would preclude participation in any aspect of the study 6. Contraindication for tDCS including a history of head injury/surgery, seizure, cardiac pacemaker, metal/electrical/magnetic implantation, uncontrolled migraine headache
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Segmental angular velocity in degrees/second | baseline and immediately after the intervention | Segmental angular velocity will be derived from the inertial measurement units. |
| Clinical observation | baseline and immediately after the intervention | Clinical observation rating will be recorded as presence or absence of aberrant movement by two raters. |
| Number of motor units | baseline and immediately after the intervention | Number of motor units will be derived from decomposition of muscle activity using electromyography system. |
| Motor unit action potential in millivolts | baseline and immediately after the intervention | Motor unit action potential will be derived from decomposition of muscle activity using electromyography system. |
| Motor unit firing rate in pulses/second | baseline and immediately after the intervention | Motor unit firing rate will be derived from decomposition of muscle activity using electromyography system. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain intensity | baseline | Pain intensity will be evaluated using numeric pain rating scale. The 11-point numeric scale ranges from '0' representing "no pain" to '10' representing "pain as bad as you can imagine" or "worst pain imaginable". |
| Level of disability in percentage | baseline | Level of disability will be evaluated using modified Oswestry Disability Questionnaire. Questionnaire examines the level of disability in 10 everyday activities of daily living. Each item consist of 6 statements which are scored from 0 to 5. With 0 indicating the least disability and 5 the greatest then the total score is calculated as a percentage, with 0% indicating no disability and 100% indicating the highest level of disability. |
| Fear of movement level | baseline | Fear of movement will be evaluated using Tampa Scale for Kinesiophobia. The 17-item Tampa Scale for Kinesiophobia total scores range from 17 to 68 where the lowest 17 means no or negligible kinesiophobia, and the higher scores indicate an increasing degree of kinesiophobia. |
| Perception of change | immediately after the intervention | Perception of change will be evaluated using a Global Rating of Change Questionnaire. It is composed of a scale (-4 to +4) that assesses whether the patient condition has gotten worse, better, or stayed the same and to quantify the magnitude of that change after exercise. In the middle of the response scale is a "0" indicating no improvement or no change, the negative values towards the left indicate worsening symptoms or a deterioration in status, and positive values towards the right indicate improvement in the health status. |
Countries
Thailand
Contacts
PRINCIPAL_INVESTIGATORPeemongkon Wattananon, PhD
Mahidol University
Outcome results
None listed