HILT Dose Optimization for Knee Osteoarthritis Pain

Inclusion Criteria: Age between 45 and 75 years, inclusive. Clinical diagnosis of knee osteoarthritis according to American College of Rheumatology (ACR) criteria (knee pain plus at least 3 of 6: age \>50, morning stiffness \<30 min, crepitus, bony tenderness, bony enlargement, no palpable warmth). Radiographic evidence of knee osteoarthritis corresponding to Kellgren-Lawrence grade II or III in the target knee. Average knee pain intensity ≥ 4 on a 10-cm Visual Analogue Scale (VAS) during weight-bearing activities in the past week. Willingness and ability to attend 3 sessions per week for 4 weeks and attend all assessment sessions. Exclusion Criteria: Previous surgery on the index knee (including arthroscopy within the last year or joint replacement). Diagnosis of inflammatory arthritis (e.g., rheumatoid arthritis, psoriatic arthritis, gout). Intra-articular corticosteroid or hyaluronic acid injection in the index knee within the last 3 months. Clinically significant comorbidities that could interfere with participation or assessment (e.g., severe uncontrolled cardiovascular disease, severe pulmonary disease, significant neurological deficits affecting the lower limb). Presence of skin conditions (e.g., infection, open wounds, eczema, photosensitivity disorders) in the area designated for laser treatment. Current use of anticoagulant medication (e.g., warfarin, DOACs) due to potential risk, unless stable and cleared by physician. (Consider if this is truly necessary based on HILT mechanism). History of cancer in the treatment area or active malignancy elsewhere. Known photosensitivity or use of photosensitizing medications. Pregnancy, planning pregnancy, or breastfeeding. Participation in another interventional clinical trial within the last 30 days. Inability to understand or communicate in the study language.