Objective: The knee joint is one of most common locations in OA. In recent years, it has been accepted that there are different pain phenotypes and patient subgroups in knee OA and that central sensitization (CS) mechanisms are at the forefront in some patients. It is also known that fear of movement, known as kinesiophobia, develops in patients with chronic pain. The aim of this study is to investigate CS and kinesiophobia in patients with knee OA, their relationships with each other, and their effects on pain intensity, functional status, pain catastrophizing and depression.

Materials and Methods: Forty-two patients with knee OA and 42 healthy subjects participated in our study. Demographic data, body mass index, habits, comorbidities, medications of participants and disease duration and radiographic grade of knee OA patients were recorded. VAS was used to assess the severity of pain and WOMAC was used to assess pain and functional status in patients with OA. Algometer (pressure pain threshold measurement) and Central Sensitization Inventory were used to evaluate central sensitization in all participants. Pressure pain threshold (PPT) was measured at 3 different points: knee joint, cruris and forearm. The presence of kinesiophobia was assessed with the Tampa Scale af Kinesiophobia (TSK). Pain Catastrophizing Scale (PCS) and Beck Depression Inventory (BDI) were used to assess chronic pain related symptoms.

Forty-two patients with knee OA and 42 healthy subjects participated in our study. Demographic data, body mass index, habits, comorbidities, medications of participants and disease duration and radiographic grade of knee OA patients were recorded. VAS was used to assess the severity of pain and WOMAC was used to assess pain and functional status in patients with OA. Algometer (pressure pain threshold measurement) and Central Sensitization Inventory were used to evaluate central sensitization in all participants. Pressure pain threshold (PPT) was measured at 3 different points: knee joint, cruris and forearm. The presence of kinesiophobia was assessed with the Tampa Scale af Kinesiophobia (TSK). Pain Catastrophizing Scale (PCS) and Beck Depression Inventory (BDI) were used to assess chronic pain related symptoms.

Inclusion Criteria for knee osteoarthritis group:

• Being a healthy volunteer between the ages of 45-75
• Being diagnosed with knee osteoarthritis according to ACR diagnostic criteria
• Knee pain for at least 6 months
• Kellgren-Lawrence 1, 2 or 3 radiologic grade of knee OA
• Body mass index below 35

Exclusion Criteria for knee osteoarthritis group:

• Presence of chronic widespread painful diseases other than osteoarthritis (fibromyalgia syndrome etc.), rheumatologic disease, peripheral neuropathy
• Presence of uncontrolled systemic disease
• Cooperation limitation or cognitive impairment
• Active arthritis in the knee joint to be evaluated
• Presence of prosthesis in the knees
• Pain in the forearm
• Body mass index of 35 and above

Inclusion Criteria for control group:

• Being a healthy volunteer between the ages of 45-75
• No pain in the knee and forearm
• No mechanical, inflammatory, endocrine, degenerative, degenerative, systemic comorbidities that may affect the knee joint
• Body mass index below 35

Exclusion Criteria for control group:

• Diagnosed with knee osteoarthritis
• Presence of uncontrolled systemic disease
• Cooperation limitation or cognitive impairment
• Presence of chronic painful disease, rheumatologic disease, peripheral neuropathy
• Body mass index of 35 and above