Knee Osteoarthritis
Conditions
Brief summary
The purpose of this research is to study the effects of Transcranial Direct Current Stimulation (tDCS) on clinical pain, mobility disability, and pain sensitivity to gain a better understanding of the factors that cause pain and disability in people with knee osteoarthritis (OA). In particular, people from different ethnic and racial groups may experience OA pain differently which is why the focus will be on older Asian Americans and non-Hispanic whites. It is important to find a reason for such difference so that a better treatment can be found for all OA patients. In addition, the research study will examine if there is any ethnic differences in pain and mobility disability. The investigator hypothesize that Asian Americans will report greater pain and mobility disability than non-Hispanic whites, and that active tDCS will result in improvement in pain and disability compared to sham tDCS.
Detailed description
If you participate in the study, the following will happen: Randomized into one of two groups. Which will either receive the full length session of brain stimulation or a much shorter session of brain stimulation. The shorter version of stimulation looks like and is performed in the same way as the longer electrical stimulation session, but stimulation is stopped before it can have much of an effect on the brain. You will not know which group you have been assigned to while participating in the research, but you may find out at the completion of the research study. X-Rays will be done on both knees while standing up. Questionnaires about arthritis pain you are having, your thoughts and feelings about it, and any stress that you may have experienced. Walking Test will be performed on a flat surface for 6 minutes at a fast pace without help from an assistive device (cane or walker) or another person. Assessment of Physical Performance requires walking at short distance (about 13 feet), stand up from a chair 5 times without using your arms, and stand in 3 different positions while keeping your balance. Assessment of Sensitivity to Heat. Heat pain sensitivity will be tested using a commercially available thermal sensory testing machine (Medoc, Inc.) used widely in clinical settings. This machine has a small (about 1 inch by 1 inch) square piece that is used to apply heat to the skin. Heat will be applied to the knees and arms. The amount of heat is controlled by a computer. One or more of the following types of heat stimuli will be delivered: 1) a slowly increasing heat that can be stopped by pressing a button when it becomes warm, painful, or intolerable; 2) a series of 5-10 heat pulses that are brief (less than 2 seconds in duration), and rate how painful each heat pulse feels; and 3) a few longer heat pulses (15-30 seconds) at different temperatures to rate how painful each heat pulse feels. The procedures can be stop at any time. Assessment of Sensitivity to Pressure will be done using a handheld device with a small rubber tip to apply pressure to the knee, thigh, and shoulder. Assessment of Sensitivity to Mechanical Stimulation will be done using a handheld probe that has a small nylon tip to tap both the knee and hand. Blood Draw: Blood will be taken at the baseline visit and at the last visit. Brain Stimulation: The stimulation technique called transcranial direct current stimulation (tDCS) and it involves placing two sponge-like electrodes on your head and delivering a very weak electrical current to your scalp, which is generated by a 9 volt battery. In addition, weekly phone calls will be done for the next 3 weeks.
Interventions
DEVICEActive tDCS
This group will receive tDCS with a constant current of 2 mA intensity will be applied for 20 minutes once a day for five consecutive days using a pair of thick (0.3 cm) rectangular surface sponge electrodes (5 cm x 7 cm) saturated with 10 mL of saline solution. The anode electrode will be placed over M1 (C3 or C4 according to the 10-20 system for EEG electrode placement) of the hemisphere contralateral to the affected knee, and the cathode electrode will be placed over the supraorbital region (SO) ipsilateral to the affected knee (M1-SO montage).
DEVICESham tDCS
This group will receive tDCS with a constant current of 2 mA intensity will be applied for 30 seconds once a day for five consecutive days using a pair of thick (0.3 cm) rectangular surface sponge electrodes (5 cm x 7 cm) saturated with 10 mL of saline solution. The anode electrode will be placed over M1 (C3 or C4 according to the 10-20 system for EEG electrode placement) of the hemisphere contralateral to the affected knee, and the cathode electrode will be placed over the supraorbital region (SO) ipsilateral to the affected knee (M1-SO montage).
Sponsors
University of Florida
The University of Texas Health Science Center, Houston
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
45 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* they have self-reported unilateral or bilateral knee OA pain according to American College of Rheumatology criteria * they can understand, speak and read English * they are able to walk for 6-minutes * they are willing to be randomized to either the intervention or control group * they are available for five consecutive daily sessions and for a follow-up phone interview each week for three weeks post-stimulation sessions * they have no plan to change medication regimens for pain throughout the trial * they are willing and able to provide written informed consent
Exclusion criteria
* knee replacement or non-arthroscopic surgery to the affected knee * serious medical illness, such as uncontrolled hypertension (i.e., Systolic Blood Pressure/Diastolic Blood Pressure of ≥ 150/95), congestive heart failure, pacemaker, or history of acute myocardial infarction * peripheral neuropathy * systemic rheumatic disorders, including rheumatoid arthritis, systemic lupus erythematosus, and fibromyalgia * alcohol/substance abuse * cognitive impairment (i.e., Mini-Mental Status Exam score ≤ 23) * history of brain surgery, tumor, seizure, stroke, or intracranial metal implantation * pregnancy or lactation for females * hospitalization within the preceding year due to psychiatric illness
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Conditioned Pain Modulation (CPM) | baseline | Conditioned pain modulation (CPM) will be done by using a cold pressor procedure on the skin. The measure is scored on a scale, which ranges from zero to infinity. A higher CPM score indicates higher pain inhibition. |
| Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Subscale | baseline | This is a index to rate the activity of pain, stiffness, and physical function based on a scale of difficulty: 0 = None, 1 = Mild, 2 = Moderate, 3 = Severe, 4 = Extreme; subscales are added up for a summation score. The higher the score, the worse the pain. |
| Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Continuous Pain Subscale | baseline | This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain. |
| Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Intermittent Pain Subscale | baseline | This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain. |
| Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Neuropathic Pain Subscale | baseline | This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain. |
| Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Affective Pain Subscale | baseline | This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain. |
| Six-minute Walk Test | baseline | The six-minute walk test (6MWT) measures the distance an individual is able to walk over a total of six minutes on a hard, flat surface. The goal is for the individual to walk as far as possible in six minutes. The individual is allowed to self-pace and rest as needed as they traverse back and forth along a marked walkway. The lower the score the worse the condition. |
| Short Physical Performance Battery (SPPB) | baseline | This is a group of measures that combines the results of the gait speed, chair stand, and balance tests. The score ranges from 0 (worst performance) to 12 (best performance). |
| Heat Pain Threshold | baseline | Quantitative Sensory Testing (QST) by using heat pain delivered by using thermal probe on the skin. |
| Heat Pain Tolerance | baseline | Quantitative Sensory Testing (QST) by using heat pain delivered by using thermal probe on the skin. |
| Pressure Pain Threshold | baseline | Quantitative Sensory Testing (QST) by using pressure pain delivered by a hand-held algometer. |
| Punctate Mechanical Pain Sensitivity | baseline | Quantitative Sensory Testing (QST) by using punctate mechanical pain delivered by a calibrated nylon monofilament. |
| Numeric Rating Scale (NRS) for Pain | baseline | Numeric Rating Scale for pain is an 101-point scale for patient self-reporting of pain on a scale of 0 to 100, with 0 being no pain at all and 100 being the worst pain imaginable. The higher the score the worse the pain. |
Secondary
| Measure | Time frame |
|---|---|
| C-reactive Protein (CRP) Level | baseline |
| Tumor Necrosis Factor (TNF) Level | baseline |
| Interleukin 6 (IL-6) Level | baseline |
| Interleukin 10 (IL-10) Level | baseline |
| Endorphin Level | baseline |
| Cortisol Level | baseline |
Other
| Measure | Time frame | Description |
|---|---|---|
| NIH PROMIS-cognition Will be Compared Between the Two Groups for a Change Between Baseline and Day 5 | Change from baseline and day 5 | A score of 50 is the average and a score of 60 is better than average. A score of 40 is the worse score. |
| Coping Strategies Questionnaire-Revised Will be Compared Between the Two Groups for a Change Between Baseline and Day 5 | Change from baseline and day 5 | This is a questionnaire to assess pain coping strategies, such as distancing from pain, using a 7-point scale that ranges from never do that to always do that. The higher the scale the greater use. |
| Positive and Negative Affect Scale Will be Compared Between the Two Groups for a Change Between Baseline and Day 5 | Change from baseline and day 5 | This is a questionnaire using a 5-point scale that ranges from very slightly or not at all to extremely. The lower the scale the negative the affect and the higher the scare the positive the affect. |
| Pain Attitudes Questionnaire-Revised Will be Compared Between the Two Groups for a Change Between Baseline and Day 5 | Change from baseline and day 5 | This is a questionnaire to assess pain attitudes, such as stoicism, using a 5-point scale that ranges from strongly disagree to strongly agree. The higher the scale the more stoic. |
| Safety Questionnaire Will be Compared Between the Two Groups for a Change Between Baseline, 1, 2, 3, 4, and 5 Days. | Change from baseline, 1, 2, 3, 4, and 5 days | This is a questionnaire to assess the presence and severity of adverse events such as headache, tingling, itching, and fatigue, on a scale of 0 to 10, with 0 being not at all and 10 being a highest degree. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Active tDCS This group will receive five daily sessions of 2mA, 20 minutes of Transcranial Direct Current Stimulation (tDCS). The anode electrode will be placed over M1 (C3 or C4 according to the 10-20 system for EEG electrode placement) of the hemisphere contralateral to the affected knee, and the cathode electrode will be placed over the supraorbital region (SO) ipsilateral to the affected knee (M1-SO montage). | 20 |
| Sham tDCS This group will receive five daily sessions of 2mA, current for 30 seconds tDCS. The anode electrode will be placed over M1 (C3 or C4 according to the 10-20 system for EEG electrode placement) of the hemisphere contralateral to the affected knee, and the cathode electrode will be placed over the supraorbital region (SO) ipsilateral to the affected knee (M1-SO montage). | 20 |
| Total | 40 |
Baseline characteristics
| Characteristic | Active tDCS | Sham tDCS | Total |
|---|---|---|---|
| Age, Continuous | 60.60 years STANDARD_DEVIATION 9.8 | 59.30 years STANDARD_DEVIATION 8.6 | 59.95 years STANDARD_DEVIATION 9.2 |
| Region of Enrollment United States | 20 participants | 20 participants | 40 participants |
| Sex: Female, Male Female | 10 Participants | 11 Participants | 21 Participants |
| Sex: Female, Male Male | 10 Participants | 9 Participants | 19 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 20 | 0 / 20 |
| serious Total, serious adverse events | 0 / 20 | 0 / 20 |
Outcome results
Primary
Conditioned Pain Modulation (CPM)
Conditioned pain modulation (CPM) will be done by using a cold pressor procedure on the skin. The measure is scored on a scale, which ranges from zero to infinity. A higher CPM score indicates higher pain inhibition.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Conditioned Pain Modulation (CPM) | 0.94 units on a scale | Standard Deviation 0.52 |
| Sham tDCS | Conditioned Pain Modulation (CPM) | 0.70 units on a scale | Standard Deviation 0.71 |
Primary
Conditioned Pain Modulation (CPM)
Conditioned pain modulation (CPM) will be done by using a cold pressor procedure on the skin. The measure is scored on a scale, which ranges from zero to infinity. A higher CPM score indicates higher pain inhibition.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Conditioned Pain Modulation (CPM) | 0.84 units on a scale | Standard Deviation 0.69 |
| Sham tDCS | Conditioned Pain Modulation (CPM) | 0.73 units on a scale | Standard Deviation 0.48 |
Primary
Heat Pain Threshold
Quantitative Sensory Testing (QST) by using heat pain delivered by using thermal probe on the skin.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Heat Pain Threshold | 42.62 Celsius | Standard Deviation 3.2 |
| Sham tDCS | Heat Pain Threshold | 40.18 Celsius | Standard Deviation 4.34 |
Primary
Heat Pain Threshold
Quantitative Sensory Testing (QST) by using heat pain delivered by using thermal probe on the skin.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Heat Pain Threshold | 41.84 Celsius | Standard Deviation 4.38 |
| Sham tDCS | Heat Pain Threshold | 40.51 Celsius | Standard Deviation 4.69 |
Primary
Heat Pain Tolerance
Quantitative Sensory Testing (QST) by using heat pain delivered by using thermal probe on the skin.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Heat Pain Tolerance | 47.07 Celsius | Standard Deviation 2.26 |
| Sham tDCS | Heat Pain Tolerance | 45.42 Celsius | Standard Deviation 3.5 |
Primary
Heat Pain Tolerance
Quantitative Sensory Testing (QST) by using heat pain delivered by using thermal probe on the skin.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Heat Pain Tolerance | 46.47 Celsius | Standard Deviation 3.01 |
| Sham tDCS | Heat Pain Tolerance | 45.04 Celsius | Standard Deviation 3.59 |
Primary
Numeric Rating Scale (NRS) for Pain
Numeric Rating Scale for pain is an 101-point scale for patient self-reporting of pain on a scale of 0 to 100, with 0 being no pain at all and 100 being the worst pain imaginable. The higher the score the worse the pain.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Numeric Rating Scale (NRS) for Pain | 27.25 units on a scale | Standard Deviation 3.35 |
| Sham tDCS | Numeric Rating Scale (NRS) for Pain | 19.00 units on a scale | Standard Deviation 1.72 |
Primary
Numeric Rating Scale (NRS) for Pain
Numeric Rating Scale for pain is an 101-point scale for patient self-reporting of pain on a scale of 0 to 100, with 0 being no pain at all and 100 being the worst pain imaginable. The higher the score the worse the pain.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Numeric Rating Scale (NRS) for Pain | 8.75 units on a scale | Standard Deviation 1.54 |
| Sham tDCS | Numeric Rating Scale (NRS) for Pain | 12.55 units on a scale | Standard Deviation 2.98 |
Primary
Pressure Pain Threshold
Quantitative Sensory Testing (QST) by using pressure pain delivered by a hand-held algometer.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Pressure Pain Threshold | 3.21 kilopascal (kPa) | Standard Deviation 1.08 |
| Sham tDCS | Pressure Pain Threshold | 2.98 kilopascal (kPa) | Standard Deviation 1.1 |
Primary
Pressure Pain Threshold
Quantitative Sensory Testing (QST) by using pressure pain delivered by a hand-held algometer.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Pressure Pain Threshold | 2.61 kilopascal (kPa) | Standard Deviation 1.13 |
| Sham tDCS | Pressure Pain Threshold | 2.63 kilopascal (kPa) | Standard Deviation 1.3 |
Primary
Punctate Mechanical Pain Sensitivity
Quantitative Sensory Testing (QST) by using punctate mechanical pain delivered by a calibrated nylon monofilament.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Punctate Mechanical Pain Sensitivity | 45.85 kilopascal (kPa) | Standard Deviation 31.94 |
| Sham tDCS | Punctate Mechanical Pain Sensitivity | 46.60 kilopascal (kPa) | Standard Deviation 25.99 |
Primary
Punctate Mechanical Pain Sensitivity
Quantitative Sensory Testing (QST) by using punctate mechanical pain delivered by a calibrated nylon monofilament.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Punctate Mechanical Pain Sensitivity | 42.23 kilopascal (kPa) | Standard Deviation 26.87 |
| Sham tDCS | Punctate Mechanical Pain Sensitivity | 50.73 kilopascal (kPa) | Standard Deviation 33.61 |
Primary
Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Affective Pain Subscale
This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Affective Pain Subscale | 1.58 units on a scale | Standard Deviation 0.51 |
| Sham tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Affective Pain Subscale | 0.66 units on a scale | Standard Deviation 0.2 |
Primary
Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Affective Pain Subscale
This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Affective Pain Subscale | 0.61 units on a scale | Standard Deviation 0.15 |
| Sham tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Affective Pain Subscale | 0.77 units on a scale | Standard Deviation 0.21 |
Primary
Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Continuous Pain Subscale
This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Continuous Pain Subscale | 2.25 units on a scale | Standard Deviation 0.48 |
| Sham tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Continuous Pain Subscale | 1.50 units on a scale | Standard Deviation 0.23 |
Primary
Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Continuous Pain Subscale
This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Continuous Pain Subscale | 1.29 units on a scale | Standard Deviation 0.22 |
| Sham tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Continuous Pain Subscale | 1.60 units on a scale | Standard Deviation 0.41 |
Primary
Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Intermittent Pain Subscale
This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Intermittent Pain Subscale | 1.75 units on a scale | Standard Deviation 0.58 |
| Sham tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Intermittent Pain Subscale | 0.98 units on a scale | Standard Deviation 0.28 |
Primary
Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Intermittent Pain Subscale
This is a index to rate the activity of pain based on a scale of difficulty: 0 = None, 1 = Mild, 2 = Moderate, 3 = Severe, 4 = Extreme. The higher the score, the worse the pain.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Intermittent Pain Subscale | 0.96 units on a scale | Standard Deviation 0.33 |
| Sham tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Intermittent Pain Subscale | 1.15 units on a scale | Standard Deviation 0.39 |
Primary
Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Neuropathic Pain Subscale
This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Neuropathic Pain Subscale | 0.54 units on a scale | Standard Deviation 0.13 |
| Sham tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Neuropathic Pain Subscale | 0.66 units on a scale | Standard Deviation 0.2 |
Primary
Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Neuropathic Pain Subscale
This is a questionnaire to rate the pain intensity and related symptoms on a scale of 0 to 10, with 0 being none and 10 being the worst possible. The higher the score the worse the pain.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Neuropathic Pain Subscale | 0.93 units on a scale | Standard Deviation 0.29 |
| Sham tDCS | Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) Neuropathic Pain Subscale | 0.80 units on a scale | Standard Deviation 0.2 |
Primary
Short Physical Performance Battery (SPPB)
This is a group of measures that combines the results of the gait speed, chair stand, and balance tests. The score ranges from 0 (worst performance) to 12 (best performance).
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short Physical Performance Battery (SPPB) | 11.25 units on a scale | Standard Deviation 0.28 |
| Sham tDCS | Short Physical Performance Battery (SPPB) | 11.05 units on a scale | Standard Deviation 0.33 |
Primary
Short Physical Performance Battery (SPPB)
This is a group of measures that combines the results of the gait speed, chair stand, and balance tests. The score ranges from 0 (worst performance) to 12 (best performance).
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Short Physical Performance Battery (SPPB) | 11.05 units on a scale | Standard Deviation 0.27 |
| Sham tDCS | Short Physical Performance Battery (SPPB) | 11.10 units on a scale | Standard Deviation 0.33 |
Primary
Six-minute Walk Test
The six-minute walk test (6MWT) measures the distance an individual is able to walk over a total of six minutes on a hard, flat surface. The goal is for the individual to walk as far as possible in six minutes. The individual is allowed to self-pace and rest as needed as they traverse back and forth along a marked walkway. The lower the score the worse the condition.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Six-minute Walk Test | 497.47 meters | Standard Deviation 16.75 |
| Sham tDCS | Six-minute Walk Test | 494.26 meters | Standard Deviation 18.77 |
Primary
Six-minute Walk Test
The six-minute walk test (6MWT) measures the distance an individual is able to walk over a total of six minutes on a hard, flat surface. The goal is for the individual to walk as far as possible in six minutes. The individual is allowed to self-pace and rest as needed as they traverse back and forth along a marked walkway. The lower the score the worse the condition.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Six-minute Walk Test | 478.18 meters | Standard Deviation 16.46 |
| Sham tDCS | Six-minute Walk Test | 490.71 meters | Standard Deviation 18.26 |
Primary
Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Subscale
This is a index to rate the activity of pain, stiffness, and physical function based on a scale of difficulty: 0 = None, 1 = Mild, 2 = Moderate, 3 = Severe, 4 = Extreme; subscales are added up for a summation score. The higher the score, the worse the pain.
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Subscale | 24.20 units on a scale | Standard Deviation 2.57 |
| Sham tDCS | Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Subscale | 19.50 units on a scale | Standard Deviation 2.93 |
Primary
Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Subscale
This is a index to rate the activity of pain, stiffness, and physical function based on a scale of difficulty: 0 = None, 1 = Mild, 2 = Moderate, 3 = Severe, 4 = Extreme; subscales are added up for a summation score. The higher the score, the worse the pain.
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Subscale | 29.30 units on a scale | Standard Deviation 3.68 |
| Sham tDCS | Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Subscale | 20.40 units on a scale | Standard Deviation 2.13 |
Secondary
Cortisol Level
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Cortisol Level | 47085.48 pg/mL | Standard Deviation 36657.95 |
| Sham tDCS | Cortisol Level | 39358.75 pg/mL | Standard Deviation 29387.62 |
Secondary
Cortisol Level
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Cortisol Level | 46588.50 pg/mL | Standard Deviation 32249.18 |
| Sham tDCS | Cortisol Level | 38853.23 pg/mL | Standard Deviation 24343.37 |
Secondary
C-reactive Protein (CRP) Level
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | C-reactive Protein (CRP) Level | 1394.33 ng/mL | Standard Deviation 1278.41 |
| Sham tDCS | C-reactive Protein (CRP) Level | 1758.26 ng/mL | Standard Deviation 2833.17 |
Secondary
C-reactive Protein (CRP) Level
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | C-reactive Protein (CRP) Level | 1496.74 ng/mL | Standard Deviation 1469.79 |
| Sham tDCS | C-reactive Protein (CRP) Level | 3372.98 ng/mL | Standard Deviation 5490.5 |
Secondary
Endorphin Level
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Endorphin Level | 0.04 ng/mL | Standard Deviation 0.02 |
| Sham tDCS | Endorphin Level | 0.05 ng/mL | Standard Deviation 0.02 |
Secondary
Endorphin Level
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Endorphin Level | 0.04 ng/mL | Standard Deviation 0.01 |
| Sham tDCS | Endorphin Level | 0.04 ng/mL | Standard Deviation 0.02 |
Secondary
Interleukin 10 (IL-10) Level
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Interleukin 10 (IL-10) Level | 5.68 pg/mL | Standard Deviation 2.85 |
| Sham tDCS | Interleukin 10 (IL-10) Level | 8.17 pg/mL | Standard Deviation 4.56 |
Secondary
Interleukin 10 (IL-10) Level
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Interleukin 10 (IL-10) Level | 6.25 pg/mL | Standard Deviation 3.2 |
| Sham tDCS | Interleukin 10 (IL-10) Level | 8.91 pg/mL | Standard Deviation 5.36 |
Secondary
Interleukin 6 (IL-6) Level
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Interleukin 6 (IL-6) Level | 2.12 pg/mL | Standard Deviation 1.78 |
| Sham tDCS | Interleukin 6 (IL-6) Level | 3.57 pg/mL | Standard Deviation 3.65 |
Secondary
Interleukin 6 (IL-6) Level
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Interleukin 6 (IL-6) Level | 2.40 pg/mL | Standard Deviation 1.43 |
| Sham tDCS | Interleukin 6 (IL-6) Level | 3.37 pg/mL | Standard Deviation 2.62 |
Secondary
Tumor Necrosis Factor (TNF) Level
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Tumor Necrosis Factor (TNF) Level | 7.63 pg/mL | Standard Deviation 3.42 |
| Sham tDCS | Tumor Necrosis Factor (TNF) Level | 10.20 pg/mL | Standard Deviation 5.78 |
Secondary
Tumor Necrosis Factor (TNF) Level
Time frame: day 5
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Active tDCS | Tumor Necrosis Factor (TNF) Level | 7.41 pg/mL | Standard Deviation 3.27 |
| Sham tDCS | Tumor Necrosis Factor (TNF) Level | 10.36 pg/mL | Standard Deviation 5.98 |
Other Pre-specified
Coping Strategies Questionnaire-Revised Will be Compared Between the Two Groups for a Change Between Baseline and Day 5
This is a questionnaire to assess pain coping strategies, such as distancing from pain, using a 7-point scale that ranges from never do that to always do that. The higher the scale the greater use.
Time frame: Change from baseline and day 5
Other Pre-specified
NIH PROMIS-cognition Will be Compared Between the Two Groups for a Change Between Baseline and Day 5
A score of 50 is the average and a score of 60 is better than average. A score of 40 is the worse score.
Time frame: Change from baseline and day 5
Other Pre-specified
Pain Attitudes Questionnaire-Revised Will be Compared Between the Two Groups for a Change Between Baseline and Day 5
This is a questionnaire to assess pain attitudes, such as stoicism, using a 5-point scale that ranges from strongly disagree to strongly agree. The higher the scale the more stoic.
Time frame: Change from baseline and day 5
Other Pre-specified
Positive and Negative Affect Scale Will be Compared Between the Two Groups for a Change Between Baseline and Day 5
This is a questionnaire using a 5-point scale that ranges from very slightly or not at all to extremely. The lower the scale the negative the affect and the higher the scare the positive the affect.
Time frame: Change from baseline and day 5
Other Pre-specified
Safety Questionnaire Will be Compared Between the Two Groups for a Change Between Baseline, 1, 2, 3, 4, and 5 Days.
This is a questionnaire to assess the presence and severity of adverse events such as headache, tingling, itching, and fatigue, on a scale of 0 to 10, with 0 being not at all and 10 being a highest degree.
Time frame: Change from baseline, 1, 2, 3, 4, and 5 days