The goal of this clinical trial is to compare whether HILT versus Sham-HILT is effective to reduce pain, improve knee joint position sense, and knee muscle strength.

Participants will undergo a single-session of HILT or Sham-HILT, the measurements of pain, knee joint position sense error, and knee muscle strength will be done at before, immediately after, and 24-hour after the single-session intervention.

The investigators would like to investigate whether single session of high-intensity laser therapy (HILT) is promising to see the changes in individuals with knee osteoarthritis (KOA)-related knee pain regarding pain intensity, knee joint position sense, and knee muscle strength.

The objectives of this study is to compare pre and post, and between the two groups (HILT versus Sham-HILT) at after interventions regarding pain, knee joint position sense, and knee muscle strength.

Participants will undergo a single-session of HILT or Sham-HILT by an experienced musculoskeletal physical therapist, the measurements of pain, knee joint position sense error, and knee muscle strength will be done at before, immediately after, and 24-hour after the single-session intervention.

Inclusion Criteria:

• knee pain greater than 3 on the Visual Analog Scale (VAS) for more than 3 months
• diagnosed with unilateral knee osteoarthritis by a physician or meeting the American College of Rheumatology Classification Criteria for clinical knee osteoarthritis
• the severity of knee osteoarthritis is classified as grades 0-3 according to the Kellgren-Lawrence (KL) classification
• should not have undergone any specific treatments in the 3 months preceding the recruitment for the study, such as steroid injections.

Exclusion Criteria:

• any other musculoskeletal problems associated with knee pain
• musculoskeletal problems associated with the hip and ankle joints
• a history of lower limb fracture
• neurological conditions
• contraindications for laser therapy

This is a pilot study