DJO UK Ltd (ENOVIS) is conducting this study to assess the effectiveness of LightForce® Therapy Lasers on pain reduction in subjects with unilateral or bilateral knee osteoarthritis. In detail this study will assess superiority of LightForce® Therapy Lasers combined with standard of care, represented by physiotherapy/exercise program compared to sham laser combined with standard of care (physiotherapy/exercise program) on pain reduction in subjects with knee osteoarthritis. In addition, this study allows to collect post market clinical data on the safety and performance of LightForce® Therapy Lasers, when used, following the normal clinical practice, in accordance with its approved and CE marked intended use.

This clinical investigation is a post-market, International, multi center, prospective, randomized, sham controlled, single blind study to assess the effectiveness of LightForce® Therapy Lasers and to collect PMCF data on the safety and performance of LightForce® Therapy Lasers, when used in accordance with its approved labeling, to comply with Medical Device Regulation (EU) 2017/745 (MDR) Article 61 and Part B of Annex XI.

Inclusion Criteria:

• Patient male or female with age ≥18 years old
• Patient with radiographic diagnosis of knee osteoarthritis (as confirmed by x- ray or CT scan) to be treated by LightForce® Therapy Lasers according its indications.
• Patient with Kellgren and Lawrence grade 2-3 unilateral or bilateral knee osteoarthritis
• Patient suffering from knee osteoarthritis pain for more than 6 months prior to enrollment
• Pain (either persistent or during activities) score reported by the subject at baseline ≥ 40 mm measured on VAS
• Patient able to provide written informed consent
• Patient with BMI ≤30 kg/m2
• For FRANCE ONLY: To be affiliated to the social security system or to be beneficiary of such system

Exclusion Criteria:

• Patient with musculoskeletal pathological conditions not to be treated with/contraindication to the use of LightForce® Therapy Lasers according to its intended use and indications
• Patients who are taking drugs that have heat or light sensitive contraindications, such as but not limited to certain types of steroids
• Patients who are administered with corticosteroids, should discontinue the treatment at least 2 weeks prior to study treatment start
• Pregnant females or females of childbearing potentially planning to become pregnant during the study participation
• Patients who had inflammatory arthritis (i.e. rheumatoid arthritis, psoriatic arthritis)
• Patients who underwent intra-articular injection (Ialuronic acid, platelet rich plasma or corticosteroids) in the knee in the last 6 months
• Patients who have a disease that would limit their participation in exercises (i.e. severe chronic obstructive pulmonary disease, severe heart failure, cerebrovascular event history)
• Patients who have hip or ankle/foot joint pathology that might interfere with participation in exercises/knee recovery
• Patients with a diagnosis of active cancer
• Patients with tattoos covering more than 30% of the area to be treated with LightForce® Therapy Lasers
• Patients who are mentally or physically incapacitated
• Patient participating in other clinical study or has completed a clinical study less than 30 days prior to enrollment
• Patients with other musculoskeletal problems of the knee joint such as tendon or ligament injury, recent surgery, recent fracture, or recent meniscus injury and/or undergoing to specific physiotherapy for these ("recent" is defined as within 30 days prior to enrollment)
• Patients with other clinically significant co-morbidities that make the patient unsuitable for study participation, at the discretion of the investigator.