Effects of chondroitin sulfate on brain response to painful stimulation in knee osteoarthritis patients. A randomized, double-blind, placebo-controlled functional magnetic resonance imaging study

Med Clin (Barc). 2017 Jun 21;148(12):539-547. doi: 10.1016/j.medcli.2016.12.036. Epub 2017 Feb 22.
[Article in English, Spanish]


Introduction: Knee osteoarthritis is causing pain and functional disability. One of the inherent problems with efficacy assessment of pain medication was the lack of objective pain measurements, but functional magnetic resonance imaging (fMRI) has emerged as a useful means to objectify brain response to painful stimulation. We have investigated the effect of chondroitin sulfate (CS) on brain response to knee painful stimulation in patients with knee osteoarthritis using fMRI.

Methods: Twenty-two patients received CS (800mg/day) and 27 patients placebo, and were assessed at baseline and after 4 months of treatment. Two fMRI tests were conducted in each session by applying painful pressure on the knee interline and on the patella surface. The outcome measurement was attenuation of the response evoked by knee painful stimulation in the brain.

Results: fMRI of patella pain showed significantly greater activation reduction under CS compared with placebo in the region of the mesencephalic periaquecductal gray. The CS group, additionally showed pre/post-treatment activation reduction in the cortical representation of the leg. No effects of CS were detected using the interline pressure test.

Conclusions: fMRI was sensitive to objectify CS effects on brain response to painful pressure on patellofemoral cartilage, which is consistent with the known CS action on chondrocyte regeneration. The current work yields further support to the utility of fMRI to objectify treatment effects on osteoarthritis pain.

Keywords: Artrosis de rodilla; Chondroitin sulfate; Condroitín sulfato; Dolor; Functional magnetic resonance image; Knee osteoarthritis; Pain; Resonancia magnética funcional.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Analgesics / pharmacology*
  • Analgesics / therapeutic use
  • Chondroitin Sulfates / pharmacology*
  • Chondroitin Sulfates / therapeutic use
  • Double-Blind Method
  • Drug Administration Schedule
  • Female
  • Follow-Up Studies
  • Humans
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Neuroimaging*
  • Osteoarthritis, Knee / drug therapy*
  • Pain Measurement / methods*
  • Pain Perception / drug effects*
  • Periaqueductal Gray / diagnostic imaging
  • Periaqueductal Gray / drug effects
  • Treatment Outcome


  • Analgesics
  • Chondroitin Sulfates