Effects of tDCS and tUS on Pain Perception in OA of the Knee

Active, not recruiting

Conditions: Chronic Pain
Osteoarthritis

Interventions: Device: Sham low-intensity transcranial electrical stimulation/sham transcranial ultrasound
Device: active low-intensity transcranial electrical stimulation/active transcranial ultrasound

Registration Number: NCT02723929

Lead Sponsor: Spaulding Rehabilitation Hospital

Brief Summary: The purpose of this study is to investigate the effects of transcranial direct current stimulation (tDCS) in conjunction with transcranial ultrasound (TUS) on pain perception and functional limitations in people with osteoarthritis of the knee. The investigators hypothesize that there will be a decrease in pain levels with active stimulation, when compared to sham stimulation.

Detailed Description: Not available

Recruitment & Eligibility

Status: ACTIVE_NOT_RECRUITING

Sex: All

Target Recruitment: 64

Inclusion Criteria

Able to provide informed consent to participate in the study.
Subjects between 18-85 years old.
Diagnosis of chronic osteoarthritis with pain of either knee as self-reported.
Existing knee pain of at least 3 on a 0-10 VAS scale on average over the past 6 months.
Pain of at least 3 on a 0-10 VAS scale on average over the week prior to the first stimulation session.
Pain resistant to common analgesics and medications for chronic pain used as initial pain management such as Tylenol, Aspirin, Ibuprofen, Soma, Parafon Forte DCS, Zanaflex, and Codeine.
Having the ability to feel pain as self-reported.

Exclusion Criteria

Pregnancy or trying to become pregnant in the next 6 months.
History of alcohol or drug abuse within the past 6 months as self-reported
Contraindications to transcranial brain stimulation or TUS, i.e. implanted brain medical devices or implanted brain metallic devices.
Unstable medical conditions (e.g. uncontrolled diabetes, uncompensated cardiac issues, heart failure or chronic obstructive pulmonary disease).
Epilepsy.
Use of carbamazepine within the past 6 months as self-reported.
Suffering from severe depression (with a score of >30 in the Beck Depression Inventory)
History of unexplained fainting spells as self-reported.
Head injury resulting in more than a momentary loss of consciousness
History of neurosurgery as self-reported.

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Sham Electrical Stim/Sham Ultrasound	Sham low-intensity transcranial electrical stimulation/sham transcranial ultrasound	Subjects will undergo sham (placebo) low-intensity transcranial electrical stimulation in conjunction with sham transcranial ultrasound for 20 minutes.
Active Electrical Stim/Active Ultrasound	active low-intensity transcranial electrical stimulation/active transcranial ultrasound	Subjects will undergo active low-intensity transcranial electrical stimulation in conjunction with active transcranial ultrasound for 20 minutes.

Primary Outcome Measures

Name	Time	Method
Changes in Pain Scale as Measured by VAS	Baseline and 8 weeks	Changes in the Visual Analogue Scale (VAS) for pain were measured in order to determine whether transcranial direct current stimulation in conjunction with transcranial ultrasound is effective in reducing pain in subjects with Osteoarthritis of the Knee. The VAS scale goes from 0 up to 10, where 0 means no pain at all and 10 means the worst imaginable pain and is reported following the full course of therapy. Since we are using a difference, smaller values (negative) represent a better outcome

Secondary Outcome Measures

Name	Time	Method
Average Daily Dose of Acetaminophen Equivalent	8 weeks	Analgesic use (average daily dose of acetaminophen equivalent)
Changes in Pain Scale as Measured by VAS	Baseline and 4 weeks post-stimulation	Changes in the Visual Analogue Scale (VAS) for pain were measured in order to determine whether transcranial direct current stimulation in conjunction with transcranial ultrasound is effective in reducing pain in subjects with Osteoarthritis of the Knee. The VAS scale goes from 0 up to 10, where 0 means no pain at all and 10 means the worst imaginable pain. Since we are using a difference, smaller values (negative) represent a better outcome.
Percentage Change in Diffuse Noxious Inhibitory Controls (DNIC) From Baseline	Baseline and 8 weeks	This measures the endogenous pain modulatory pathway. This study will evaluate DNIC in pain patients using pressure as the test stimulus, and cold water as the conditioning stimulus. DNIC will be induced approximately 1-min later by having subjects immerse their hand into a water bath maintained at 10-12˚C for approximately 1 min. Parallel to the last 30s of DNIC conditioning (cold water immersion), the pressure test stimulus will be reapplied. DNIC response will be calculated as the difference between the average of pain ratings from the test stimulus minus the average of pain ratings during the conditioned stimulus. Larger percentage change means a better outcome.
Percentage Change From Baseline in the Single Leg Standing Balance Test	Baseline and 8 weeks	We will record the time (seconds) for which a subject is able to stand unsupported on one foot while looking straight ahead with hands on hips. Larger percentage change means a better outcome.
Percentage Change From Baseline in the Step Test	Baseline and 8 weeks	The subject was asked to stand unsupported with their feet parallel to each other in front of a step. We assessed the number of times the participant could place their foot up onto the step and return it to the floor over a 15-sec interval. Larger percentage change means a better outcome.
Percentage Change in Functional Reach Test From Baseline	Baseline and 8 weeks	Subject will be instructed to stand next to, but not touch the wall, and position the arm that is closer to the wall at 90 degrees of shoulder flexion with a closed fist. Smoothness of wrist movement is assessed as the subject was asked to outstretch their arm in a maximal forward reach, while maintaining a fixed base of support. Smoothness is dimensionless and is calculated as mean speed divided by peak speed. Larger percentage change means a better outcome.