Transcranial Direct Current Stimulation and Yoga for Knee Osteoarthritis

Knee Osteoarthritis Clinical Trial

Official title:

Combining Transcranial Direct Current Stimulation and Yoga for Improved Pain Management for Knee Osteoarthritis: A Pilot and Feasibility Trial

Clinical Trial Details — Status: Not yet recruiting

Administrative data

• NCT number: NCT06228573
• Other study ID #: 23-0000000177
• Status: Not yet recruiting
• Phase: N/A
• Start date: May 15, 2024
• Est. completion date: August 31, 2025

Study information

• Verified date: January 2024
• Source: McMaster University
• Contact: Lisa Carlesso, PhD
• Phone: 2896805640
• Email: carlesl[@]mcmaster.ca
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

People with knee arthritis often experience constant pain, and current treatments aren't very effective. This can lead to limited movement and more health problems. Knee arthritis is a big part of healthcare costs in Canada, and its pain is a major reason people see doctors. The pain is linked to complex nervous system changes, making current treatments, like exercise, not very successful.

To address this, researchers suggest a new approach combining two things: a brain stimulation technique called Transcranial Direct Current Stimulation (tDCS) and yoga. TDCS helps with pain by changing how the brain works, and yoga, a safe practice, focuses on overall well-being. Together, the investigators aim to improve how the nervous system works from top to bottom.

The research project wants to change how the arthritis pain is being managed by focusing on how it works. The investigators plan to test this combo in a study comparing real tDCS plus yoga with fake tDCS plus yoga. The investigators will look not only at pain but also at other measures related to pain and how the nervous system works. This new mix could be a meaningful way to reduce pain for people with knee arthritis.

Description:

Background:

'Omnipresent' is a common word that people living with knee osteoarthritis (KOA) use to describe the associated pain, with its unpredictability causing physical, social and emotional disruption. For many, KOA pain leads to limited mobility, reduced quality of life and increased healthcare costs KOA pain and its mechanisms are known to be complex, with alterations in nervous system signaling (ANSS) leading to persistent pain, and treatment failure to guideline-based care. Unfortunately, there is a lack of effective conservative treatments for KOA pain, including exercise which elicits only modest analgesic effects and has little impact on ANSS. To improve conservative pain management for people with KOA, it is imperative to design mechanism informed interventions and explore bold new ways to modulate ANSS to optimize patient outcomes.

The investigators' novel intervention is focused on addressing the biomarker of ANSS. The investigators' solution involves using non-invasive brain stimulation (NIBS) in the form of transcranial direct current stimulation (tDCS), paired with the mind-body practice of yoga, to modify neural pathways. This is a promising and safe alternative to medications - which risk habituation, adverse events, and addiction - and that builds on the limited efficacy of performing/examining exercise in isolation. To the investigators' knowledge, this is the first trial to use this combination for chronic pain and in people with KOA. The investigators have chosen this combination as tDCS has the potential to produce synergistic nervous system effects with yoga and bolster impacts on pain.

tDCS alleviates pain in older adults with KOA, particularly when combined with strengthening exercise or mindfulness. tDCS has demonstrated improved efficiency of conditioned pain modulation (CPM) resulting in pain reduction in older adults with KOA displaying deficient CPM. Meta-analyses of tDCS for the treatment of chronic pain report small to moderate effects on pain reduction, while a meta-analysis of NIBS (including tDCS) plus exercise showed moderate to large effect sizes (-0.62) compared to sham NIBS plus exercise.

The investigators' approach combining 13 sessions of tDCS with yoga provides the benefits of strengthening and mindfulness in addition to nervous system regulation with the potential to produce large effects for pain reduction.

Yoga modulates brain networks and is safe and accessible for many with KOA Importantly, yoga is safe for people with comorbidities through its combination of physical postures, breathing exercises, meditation and relaxation that are hypothesized to reduce pain by regulating top down and bottom-up input into the physiological systems modulating nociceptive signals. Evidence from fMRI studies indicates that yoga modifies functional connectivity in networks involved in chronic pain. Yoga is conditionally recommended by KOA guidelines due to low quality evidence and few studies.

The current project seeks to shift the current paradigm for conservative pain management for people with KOA by assessing a pain mechanism informed treatment strategy in a multi-center pilot and feasibility randomized controlled trial. The investigators hypothesize that real tDCS and yoga will provide clinically meaningful reductions in pain compared to sham tDCS and yoga.

This is a feasibility and pilot double-blind, randomized sham-controlled multi-center, two-arm clinical trial with a 1:1 allocation ratio. Participants will be randomized to receive active or sham tDCS and yoga for 9 weeks. Follow-up will occur at the end of the intervention and at 3 months. The Conceptual Framework for Defining Feasibility and Pilot studies, and the Standard Protocol Items- Recommendations for Intervention Trials will be used. Study results will be reported using the extended CONSORT guideline for pilot trials and the Check List Standardizing the Reporting of Interventions For Yoga (CLARIFY).

Recruitment information / eligibility

• Status: Not yet recruiting
• Enrollment: 68
• Est. completion date: August 31, 2025
• Est. primary completion date: May 15, 2025
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 45 Years and older

Eligibility

Inclusion Criteria:

• community dwelling adults from Sherbrooke, Quebec, Hamilton and London, Ontario fulfilling the NICE criteria for KOA

• =45 years of age

• Diagnosis of Knee osteoarthritis OR

• Having movement-related joint pain with either no morning knee stiffness or stiffness of 30 minutes or less AND

• Experiencing an average pain intensity of =3 /10 in the past month

Exclusion Criteria:

• Systemic inflammatory arthritis.

• Any knee injection in the past 3 months.

• Inability to independently get up and down from the floor.

• Lower limb trauma or surgery within the last 6 months.

• Current participation in another OA clinical trial.

• Use of mobility aids.

• Currently receiving care for KOA pain (e.g., physiotherapy).

• Planned absences exceeding 1 week.

• Contraindications to transcranial direct current stimulation (tDCS) such as neurological or neuropsychiatric conditions.

• History of brain surgery or tumor.

• Metallic implants.

• Epilepsy or history of substance abuse or dependence.

• Cochlear or ocular implant.

• Presence of a pacemaker or cardiac defibrillator.

• Eczema on the scalp.

Related Conditions & MeSH terms

• Knee Osteoarthritis
• Osteoarthritis
• Osteoarthritis, Knee

Intervention

Procedure:
• Yoga
Yoga program: In weeks 2-9, participants will attend twice weekly 1-hour sessions of yoga led by a certified yoga instructor trained in the intervention by collaborator Pearson. Videos will be provided for completion of home sessions. The yoga program is based on the Pain Care Aware certification program.38 Details of the program as well as the training of instructors are provided in the appendices. Briefly, classes will consist of 3 parts: centring and warming up aimed at regulating physiology prior to beginning the yoga postures; yoga postures and guided relaxation.

Locations

Country	Name	City	State
Canada	McMaster University	Hamilton	Ontario

Sponsors (2)

Lead Sponsor	Collaborator
McMaster University	The Arthritis Society, Canada

Country where clinical trial is conducted

Canada, 

References & Publications (40)

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* Note: There are 40 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Percentage of complete follow up	Percentage rate measured by those at baseline completing study follow up measures	9 weeks and 3 months
Secondary	Brief Pain Inventory - Numeric Rating Scale	The BPI uses 4 questions to ask about worst and least pain intensity in the past 24 hours, pain on average and pain right now. Questions are rated on an 11-point scale where patients select a rating between 0-10 with zero representing 'no pain' and 10 representing the 'worst imaginable pain'. The Numeric Rating Scale is reported to have excellent inter-rater reliability and acceptable validity in people with KOA.	9 weeks and 3 months
Secondary	Modified Charlson Comorbidity Index (CCI)	To assesses the presence of 19 comorbidities in participants. The CCI has been used in many patient populations including knee osteoarthritis	9 weeks and 3 months
Secondary	Endogenous pain modulation	CPM will be assessed in the following steps: 1) at the anterior shin on the unaffected knee, an ascending measure of pressure pain threshold (PPT) will be evaluated, inducing a pain rating of 3/10. 2) At the opposite volar forearm, a conditioning stimulus in the form of forearm ischemia using a blood pressure cuff and squeezing a stress ball until a pain rating of 5/10 is reached, 3) PPT at the anterior shin will be repeated with the cuff remaining inflated2, 4) an index will be created by calculating the percent efficiency of CPM (%CPM) as PPT2/PPT1, multiplied by 100; whereby %CPM = 100 indicates inefficient pain modulation. CPM testing has demonstrated good intra-session reliability.	9 weeks
Secondary	Pain interference	The Brief Pain Inventory5 assesses pain interference through 7 items general activity, mood, walking, normal work, relations with others, sleeping, enjoyment of life rated from 0 (does not interfere) to 10 (completely interferes).	9 weeks and 3 months
Secondary	Pain catastrophizing	Pain Catastrophizing Scale (PCS); The PCS is a 13-item self-reporting instrument for catastrophizing in the context of actual or anticipated pain, with higher scores indicating higher pain catastrophizing. The validity of the PCS for measuring pain catastrophizing in people with KOA has been reported.	9 weeks and 3 months
Secondary	Hospital Anxiety and Depression Scale (HADS)	The HADS is a brief and reliable measure of emotional distress in general in chronic populations. Validity and reliability of the HADS have been previously established. Higher scores on the HADS indicate increased severity of anxiety and depression symptoms.	9 weeks and 3 months
Secondary	Knee Injury and Osteoarthritis Outcome Score (KOOS)	The KOOS pain and function in daily living and QoL subscales will be used to assess self-reported opinions about patients' knee and associated problems. Scores range from 0-100 with zero representing extreme knee problems and 100 representing no knee problems. KOOS has adequate internal consistency and validity in people with KOA.	9 weeks and 3 months
Secondary	Multi-joint pain; Body diagram	Participants will be asked to indicate any other areas where they experience pain (e.g., neck, shoulders, back) on a body diagram which will be summed to form a count. Body diagrams are a reliable method for indication of painful body parts.	9 weeks and 3 months
Secondary	Knee Awareness	Fremantle knee awareness questionnaire; Developed from the low back version, the scale has good reliability and is correlated with pain in motion, disability, catastrophizing, fear of movement, and anxiety. It consists of 9 items rated from never to always. Higher scores indicate lower knee awareness.	9 weeks and 3 months
Secondary	Functional leg strength	Stair climb test; The OARSI recommended test will measure the time (in seconds) it takes to ascend and descend a flight of stairs consisting of 9 steps and a handrail. The test has excellent reliability and responsiveness.	9 weeks
Secondary	Medication use	Survey question; Participants will be asked to indicate use of any SSRI or SNRI medication that they take regularly and which can impact neuromodulation. Use of these medications will be adjusted for in our model	9 weeks and 3 months
Secondary	Adverse events	Survey question; We will monitor adverse events related to tDCS using the following questionnaire: Do you experience any of the following symptoms or side-effects? Headache Neck pain Scalp pain Tingling Itching Burning sensation Skin redness Sleepiness Trouble concentrating Acute mood change Others (specify) rated as absent, mild, moderate or severe and then If present: Is this related to tDCS? (1, none ; 2, remote; 3, possible; 4, probable; 5, definite).; We will also monitor adverse events related to yoga by asking the participants to report any problems that they experience after the yoga class that last for more than two days and/or urged them to seek treatment or if they experience any adverse events during the class (such as falls or injuries)	9 weeks
Secondary	Patient global impression of change	At the end of the program, participants will be asked to rate the amount of change on a 7 point scale experienced ranging from very much improved to very much worse. The scale is widely used and validated as a measure of minimally important change	9 weeks and 3 months
Secondary	Blinding effectiveness	Participants will be asked to indicate which intervention group they believed they were in.	3 months
Secondary	Usefulness of the program for managing knee OA measured on a 5 point Likert scale	Likert scale anchored from Not useful at all to very useful	9 weeks
Secondary	Frequency of the program measured on a 5 point Likert scale	Likert scale anchored from not frequent enough to Frequent enough	9 weeks
Secondary	Duration of the program on a 5 point Likert scale	Likert scale anchored from not long enough to long enough	9 weeks
Secondary	Acceptability of the delivery of the brain stimulation on a 5 point Likert scale	Likert scale anchored from not at all accepted to very acceptable	9 weeks
Secondary	Acceptability of the delivery of the yoga session of the program on a 5 point Likert scale	Likert scale anchored from not at all accepted to very acceptable	9 weeks
Secondary	How likely are you to recommend the program you attended for others with knee OA?	Likert scale anchored from not at all likely to very likely	9 weeks
Secondary	How burdensome did you find completing the questionnaires?	10 point scale- burdensomeness rating between 0 (no burden at all) to 10 (very much a burden)	3 months
Secondary	How burdensome did you find completing the physical assessments?	10 point scale- burdensomeness rating between 0 (no burden at all) to 10 (very much a burden)	9 weeks
Secondary	rate of adherence measured by percentage of sessions attended and home sessions completed	adherence rate calculated from attendance and exercise tracking sheets	9 weeks