Clinical Trial: Investigation of the Efficacy of tDCS in the Treatment of Complex Regional Pain Syndrome (CRPS) Type 1

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Investigation of the Efficacy of Transcranial Direct Current Stimulation (tDCS) Added to the Graded Motor Imagery (GMI) in the Treatment of Complex Regional Pain Syndrome

Brief Summary: The efficacy of the current standard non-pharmacological treatments for complex regional pain syndrome (CRPS), a painful syndrome mostly occurring after musculoskeletal trauma, is suboptimal. It thus appears essential to examine new non-pharmacological therapeutic imagery (GMI) - a non-pharmacological approach with the highest level of evidence (level II). As suggested by the most recent clinical guideline 2, a potential solution would be to add an electrotherapeutic procedure - transcranial direct current stimulation (tDCS) - that may prove effective in modulating cortical excitability and reducing the effect of cortical reorganization on pain. Given the positive results previously obtained in patients with neuropathic pain, it is hypothesized that tDCS will prove to be an innovative add-on treatment method for CRPS patients, and help reduce pain and disability.

Detailed Summary:

Executive summary: The efficacy of the current standard rehabilitation treatments for complex regional pain syndrome (CRPS), a painful syndrome mostly occurring after musculoskeletal trauma, is suboptimal. For instance, the first line of treatment in rehabilitation, progressive motor imagery (GMI), only induces a 50% improvement in symptoms. Although such improvement is interesting, further solutions should be sought to enhance clinical outcomes. It is thus essential to explore new options of therapy. A potential solution to enhance clinical outcomes would be to add an electrotherapeutic procedure, such as transcranial direct current stimulation (tDCS). Given the positive results previously obtained in patients with neuropathic pain, we hypothesize that tDCS will induce functional and structural reorganization in the cortex and lead to better pain relief. The cortical reorganization frequently observed in CRPS patients mainly involves a shrinkage of cortical map of the affected limb on primary and secondary somatosensory cortex. Interestingly, therapies that aim to reverse the cortical reorganization are often associated with a decrease in pain. Therefore, combining GMI and tDCS could lead to added pain relief compared to traditional GMI treatments alone. Furthermore, neuroimaging before and after the procedures could help us explain if and how this is achieved. Objectives: Thus, the primary objective of this research is to study the therapeutic efficacy of tDCS in the treatment of CRPS type 1 in addition to the current best evidence-based rehabilitation treatment, GMI. The second objective is to study, through MRI/fMRI, how brain structures and functions are changed following tDCS and GMI treatments, and whether these changes correlate to clinical changes.

Methodology: To achieve the first objective, we will recruit adults diagnosed with CRPS type 1 via established colla
Sponsor: Université de Sherbrooke

Current Primary Outcome: Pain Severity [ Time Frame: Before (T0) and after treatment (6 weeks) (T1) ]

Original Primary Outcome: The global impression of change [ Time Frame: after end of treatment, 1 and 3 months follow-up ]

Current Secondary Outcome:

• Pain Catastrophizing [ Time Frame: Before (T0) and after treatment (6 weeks) (T1) ]

  The Pain catastrophizing scale (PCS) (Sullivan et al., 1995) was used to evaluate the feelings, thoughts, and emotions related to pain catastrophizing of the patient. The PCS instructions ask participants to reflect on past painful experiences, and to indicate the degree to which they experienced each of 13 thoughts or feelings when experiencing pain, on 5-point scales with the end points (0) not at all and (4) all the time. The PCS yields a total score and three subscale scores assessing rumination, magnification and helplessness.

  * The scores ranging from 0 to 52 points (sum of the tree subscales), with higher scores representing stronger pain catastrophizing (Sullivan et al., 1995).

• Kinesiophobia [ Time Frame: Before (T0) and after treatment (6 weeks) (T1) ]
  The Tampa Scale of kinesiophobia (TSK) (Kori et al., 1990) was used to assess fear of movement and injury/(re)injury. The TSK questionnaires consist of 17 items. Each item, composed of a statement, is scored by the patient on a 4-point Likert scale of 1 (strongly disagree) to 4 (strongly agree). The total scores range from 17 to 68, with higher scores representing stronger fear-avoidance beliefs (Clark, Kori, Brockel, 1996).
• State Anxiety [ Time Frame: Before (T0) and after treatment (6 weeks) (T1) ]
  The State-Trait Anxiety Inventory (STAI) was used to assess the state of anxiety at the moment (Spielberg et al., 1983). The total score is obtained by adding the scores for all 20 questions range from 20 to 80; the higher the result is, the higher is the anxiety about an event.

Original Secondary Outcome:

• The clinical pain and global physical function [ Time Frame: after end of treatment, 1 and 3 months follow-up ]
  short form Brief Pain Inventory
• The perception of the specific function of the upper limb [ Time Frame: after end of treatment, 1 and 3 months follow-up ]
  Disabilities of the Arm, Shoulder and Hand questionnaire on functional disability
• The perception of the specific function of the lower limb [ Time Frame: after end of treatment, 1 and 3 months follow-up ]
  Lower extremity version of the Impairment Sum Score
• The impact of pain on health-related quality of life [ Time Frame: after end of treatment, 1 and 3 months follow-up ]
  sf-12

Dates:
Date Received: September 24, 2013
Date Started: April 2013
Date Completion:
Last Updated: December 13, 2016
Last Verified: December 2016