The Effect of Combining Pain Neuroscience Education and Transcranial Direct Current Stimulation on Pain Catastrophizing, Kinesiophobia, and Pain in Patients With Chronic Low Back Pain

The Effect of Combining Pain Neuroscience Education and Transcranial Direct Current Stimulation on Pain Catastrophizing, Kinesiophobia, and Pain in Patients With Chronic Low Back Pain

Recent literature has shown that individuals with persistent chronic pain often exhibit altered cognitive, affective, and sensorimotor behaviors despite a full recovery of peripheral structural injury. Clinically this can be observed via altered pain behaviors (e.g., pain catastrophizing and kinesiophobia) and increased sensitivity to pressure stimuli, each of which are predictive of poorer outcomes. These alterations are believed to have arisen from maladaptive reorganization of brain networks, including cognitive-evaluative and affective networks. Structurally, decreased gray matter in the dorsolateral prefrontal cortex (DLFPC), a key area in the cognitive-affective processing of pain, has been found in those suffering from chronic musculoskeletal pain. The changes are shown to be reversible when the pain is successfully treated and uniquely connected to cognitive-affective behaviors in that as catastrophizing or fear decreases, DLPFC density increases.

Pain science education (PNE), a cognitive-behavioral intervention, has shown promising effects, especially on cognitive- affective behaviors. Non-invasive brain stimulation, such as transcranial direct current stimulation (tDCS), has also been shown to reduce pain and pain-associated behavioral changes in chronic pain. However, the combined effects of these two interventions have not been investigated. It remains unclear if priming the cognitive-affective circuitry that is conceptualized to support PNE with tDCS will augment the behavioral effect of PNE. Therefore, the primary objective of this pilot study is to examine the effects of combining PNE and tDCS on pain catastrophizing, kinesiophobia, and hypersensitivity to pressure stimuli in patients with chronic low back pain (CLBP). We will also examine the influence of PNE and tDCS on cortical network patterns in a subgroup of participants. The results of this pilot study could support the use of tDCS as a priming agent to increase the effect of cognitive-behavioral interventions such as PNE. With success, this intervention could be safely and easily replicated in the clinical setting and provide a novel approach to treating chronic pain more effectively. In addition, the outcomes can further the understanding of more precisely matching specific cortical targets with the desired behavioral therapy

Inclusion Criteria:

• Reports chronic low back pain defined as a back pain problem that has persisted at least 3 months and has resulted in pain on at least half the days in the past 6 months
• Age: 18-65 years
• Score >30 on Pain Catastrophizing Scale

Exclusion Criteria:

• History of previous lower back surgery
• Systemic joint disease (e.g. rheumatoid arthritis)
• Evidence of red flags (e.g. fracture, infection, tumor, cauda equina syndrome)
• Cancer
• Neurological disorders
• Neuropathy
• Raynaud's disease
• Pregnancy
• An inability to maintain the testing and treatment positions (i.e. sitting for >30 minutes).
• Exclusion criteria for the tDCS include:
• A history of significant head trauma
• An electrical, magnetic, or mechanical implantation (e.g. cardiac pacemakers or intracerebral vascular
• clip)
• A metal implant in the head or neck areas
• A history of seizures or unexplained loss of consciousness
• An immediate family member with epilepsy
• The use of seizure threshold lowering medicine
• The current abuse of alcohol or drugs
• A history of psychiatric illness requiring medication controls