Motor Cortex Plasticity and the Effect of Deep Intramuscular Needling Stimulation Therapy (DIMST) in Osteoarthritis Pain

The aim of this study is to evaluate the cortical excitability in pain of knee osteoarthritis (OA), as well as the effect of one session of a kind of electroacupuncture (deep needling intramuscular stimulation therapy - DIMST) in this pain and the cortical excitability after the intervention. The hypothesis is that cortical excitability is altered in this condition, confirming the findings already described in other chronic pain conditions. The investigators also believe that a session DIMST can reduce pain and alter cortical excitability, restoring its previous activity will occur from chronic pain.