fMRI Evaluation of Pain Central Sensitization Phenomena in Subjects With Knee Osteoarthritis
The aim of this project is to investigate fMRI ability to identify pain central sensitization in chronic knee OA. Patients with high and low central sensitization and healthy control subjects will be included. Central sensitization will be clinically defined based on the evidence of regional spread of pain (spreading sensitization) and increased pain response to repeated stimulation (temporal summation). Operatively, a patient will be assigned to high sensitization group when showing (i) clinical evidence of pain or altered sensations spread beyond the knee joint by manual palpation, (ii) a minimum of 3 anatomical sites around the knee showing a pressure pain threshold below 4 kg/cm2 (tender points), (iii) pain score of 4 points or more in a 11-point scale during 4 kg/cm2 pressure stimulation on the anterior/medial surface of the tibial bone (the site selected for the fMRI experiment) and (iv) increase of at least 1 point in a 11-point scale after 10 repeated pressure stimulation on the tenderest point around the knee.
A three-step strategy is proposed to characterize the phenomenon by assessing (i) brain response to direct pressure stimulation on the painful knee, which will reflect the combination of peripheral and central sensitization; (ii) brain response to pressure stimulation on a non-arthritic hyperalgesic area (i.e., the anterior surface of the tibia), which will mostly reflect central sensitization mediated at the spinal cord level, and (iii) brain response to moderately painful heat stimulation on a healthy skin area (i.e., volar forearm), which will reflect central sensitization occurring in the brain and involving the highest-level pain modulatory mechanisms. An additional evaluation is proposed using resting-state fMRI to assess potential alterations in baseline brain functional organization.
|Study Design:||Observational Model: Case-Crossover
Time Perspective: Cross-Sectional
|Official Title:||fMRI Evaluation of Pain Central Sensitization Phenomena in Subjects With Knee Osteoarthritis|
- Blood oxygenation level dependent (BOLD) in response to pressure stimuli applied to the knee using fMRI [ Time Frame: Baseline ]BOLD in response to pressure stimuli applied to the knee assessed using fMRI, that measures endogenous haemodynamic signal reflecting blood oxygenation changes linked to neuronal activity.
- BOLD in response to painful contact heat stimuli applied to healthy forearm skin assessed using fMRI [ Time Frame: Baseline ]BOLD in response to painful contact heat stimuli applied to healthy forearm skin assessed using fMRI, that measures endogenous haemodynamic signal reflecting blood oxygenation changes linked to neuronal activity.
- BOLD during resting-state using fMRI [ Time Frame: Baseline ]BOLD during resting-state using fMRI, that measures endogenous haemodynamic signal reflecting blood oxygenation changes linked to neuronal activity.
|Study Start Date:||September 2012|
|Study Completion Date:||October 2016|
|Primary Completion Date:||July 2014 (Final data collection date for primary outcome measure)|
OA patients with HIGH central sensitization
Central sensitization will be defined by the presence of both spreading sensitization and temporal summation to repeated pressure pain stimulation (Arendt-Nielsen et al. 2010, Graven-Nielsen et al. 2010, Woolf 2010, Imamura et al. 2008, Nijs et al. 2010).
|OA patients with LOW central sensitization|
Please refer to this study by its ClinicalTrials.gov identifier: NCT01700634
|Jordi Monfort Faure|
|Barcelona, Spain, 08003|