None listed
Conditions
Brief summary
Low back pain (LBP) is one of the most common reasons for people to seek health care. Of those that report LBP, 44-78% experience a re-occurrence within 12 months, and approximately 25% of individuals develop chronic pain. Despite high prevalence, current treatments for chronic LBP demonstrate at best, small effect sizes. One avenue to improve outcomes in chronic LBP is through the application of combined treatments with synergistic clinical and mechanistic effects. Sensorimotor retraining is a novel treatment that incorporates motor control exercise and lumbar tactile retraining and has been shown to be effective in early randomized controlled trials and case studies of chronic LBP. The mechanism underpinning improvements in pain and function with sensorimotor retraining is thought to involve normalization of motor and sensory cortical plasticity and improved pain system function. The addition of a second treatment that targets similar mechanisms may boost the effectiveness of sensorimotor retraining in people with chronic LBP. Transcranial direct current stimulation (tDCS), a form of non-invasive brain stimulation, is thought to promote cortical plasticity and improve pain system function through direct effects on the cortex and thalamus, as well as “downstream” effects on the anterior cingulate cortex and upper brainstem. Studies of healthy individuals and people with some forms of chronic pain suggest that anodal tDCS applied to the primary motor cortex can reduce pain. In addition, the cortical effects of tDCS are hypothesised to increase the brain’s receptiveness to other treatments, a phenomenon known as priming. Thus, tDCS may optimise the responsiveness of the brain to sensorimotor retraining and improve outcomes beyond that which can be achieved with sensorimotor retraining alone. Despite this, no study has examined the effect of a combined tDCS and sensorimotor retraining therapy in chronic pain. This pilot RCT protocol will outline study methods, and resources required in order to determine the feasibility, acceptability and safety of tDCS combined with sensorimotor retraining for people with chronic LBP. The specific aims are to i) determine the feasibility, safety, perceived patient response to, and acceptability of, a combined tDCS and sensorimotor training intervention in chronic LBP and ii) provide data to support a sample size calculation for a fully powered trial should trends of effectiveness be present.
Interventions
Active transcranial direct current stimulation (tDCS) plus sensorimotor retraining will be given twice per week for 10 weeks by a qualified physiotherapist trained in the use of tDCS.
Active tDCS: will be delivered to the primary motor cortex while participants are comfortably and quietly seated. Direct current will be delivered for 20 minutes via two 35cm2 surface sponge electrodes. The active electrode (anode) will be positioned over the primary motor cortex contralateral to the side of worst
Active transcranial direct current stimulation (tDCS) plus sensorimotor retraining will be given twice per week for 10 weeks by a qualified physiotherapist trained in the use of tDCS. Active tDCS: will be delivered to the primary motor cortex while participants are comfortably and quietly seated. Direct current will be delivered for 20 minutes via two 35cm2 surface sponge electrodes. The active electrode (anode) will be positioned over the primary motor cortex contralateral to the side of worst pain and the reference electrode (cathode) over the contralateral supraorbital region. Current intensity will be ramped up (0 mA to 1 mA) and down (1 mA to 0 mA) over 10 s at the beginning and end of the 20-min stimulation period. Sensorimotor retraining: Immediately following the tDCS intervention, participants will commence 60 minutes of supervised graded sensorimotor retraining. Components of the protocol include localisation and graphesthesia training, laterality recognition, imagined movements and small to full range movements with feedback. Participants will progress through each stage by the physiotherapist based on specific, previously published criteria such as > 80 % accuracy on tactile discrimination or successful dissociation of lumbar from thoracic spine movements (Wand et al 2011). Participants will be provided with a home exercise diary containing visual and written instructions for each exercise (including dosage) and will be asked to practice the training at home for 30 minutes, 3 x per week. The diary will also be used to record adherence to the home program.
Sponsors
Siobhan Schabrun
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
Participants with chronic non-specific LBP will be recruited. Participants will be required to have an average pain score greater than or equal to 4/10 on a numerical rating scale in the week prior to enrolment and a minimum score of 4 points on the Roland Morris Disability Questionnaire (RMDQ) to limit the potential for floor effects.
Exclusion criteria
Participants will be excluded if they: i) present with specific spinal pathology (tumour, spondylolythesis, fracture etc.), nerve root pain or co-existing major muscular, joint, neurological or psychiatric conditions (Airaksinen et al., 2006; Saragiotto et al., 2016), ii) have undergone back surgery, iii) are currently undertaking a structured exercise program for LBP, or (vi) present with contraindications to tDCS (e.g. cuts or blisters under the electrode sites) or conditioned pain modulation techniques (e.g. loss of sensation).
Outcome results
None listed