Inclusion criteria:
Diagnosis of osteoarthritis in one or both knees by an orthopedic specialist for these patients (having at least three of the six criteria of the American College of Rheumatology, including age over 50 years, morning stiffness less than half an hour, tenderness in bone margins, crepitus in active joint movements, bone enlargement and no palpable increase in temperature
People aged 50 to 70 who are willing and eager to enter the study and can cooperate in various stages of evaluation, treatment and follow-up
Grade two or three of diseases in the knee osteoarthritis classification system (Kllgren and Lawrence system classification) according to a radiograph that was taken at most one year ago
minimum pain intensity of four out of ten (while walking in the last week) in Visual analogue scale of pain.
Exclusion criteria:
Traumatic knee injuries
Acute joint inflammation
Rheumatology diseases such as Rheumatoid arthritis, lupus erythematosus and Fibromyalgia, Neurological diseases that affect the function of the lower limbs, such as stroke, Parkinson's disease, MS, peripheral neuropathy and a history of seizures or their occurrence, severe headaches after the first session of receiving the electrical current, mental and cognitive problems (Mini-Mental Status Exam score ≤ 23),Cardiovascular problems such as high blood pressure or heart attack
History of surgery (such as joint replacement or tibial osteotomy) in one or both knees, history of head surgery, Brain tumor or metal implant in the head, history of lower limb surgery in the last six months
Inability to walk without an assistive device, receiving treatment or rehabilitation services for knee osteoarthritis in the last three months
Taking drugs that affect the central nervous system such as dextromethorphan and D-cycloserine in the last six months
Drug or alcohol abuse
Being hospitalized for the past year due to mental illnesses