The aim of this study is to compare the effectiveness of intra-articular injection of ozone with corticosteroids versus plasma rich in growth factors (PRGF) in improvement of pain in knee osteoarthritis patients.

Knee osteoarthritis (OA) is a prevalent degenerative condition in which functional impairment is caused by mechanical and chemical stress against the joint, resulting in pain and decreased range of motion (ROM) .

A multiplicity of treatments has been suggested for this disease : some of which include patient education, medication, exercise prescription, conventional and physical agent modalities such as pulsed radio-frequency, and surgical management , The current therapeutic options available for knee osteoarthritis are not effective and satisfactory for patients, and pain has been complained of by at least 40% of those cases who underwent surgical arthroplasty , Also old age prevalence of knee osteoarthritismake treatment with analgesics has several side effects over stomach, liver and kidney and also surgical one has high morbidities and mortalities for old ages. Therefore, in the last two decades, a large body of work has been performed to develop non-operative or minimally invasive interventions to decrease Knee osteoarthritis symptoms or slow down its progression.

Among These modalities of intra-articular injections the autologous PRP has gained more attention in the treatment of patients with knee osteoarthritis in recent years. Several studies is supporting the use of PRP injection as an effective method for Knee osteoarthritis, as latelet-rich plasma (PRP) could serve as anti-nociceptive and induce cell proliferation. also intra-articular injection of latelet-rich plasma modulates joint environment, promote chondrogenesis and inhibits the destruction of knee joint probably by reducing the production of pro-inflammatory mediators by the supra-physiologic concentrations of biological molecules and growth factors exist in in the granules of the platelets which could potentially reverse the catabolic environment in osteoarthritis, balancing the homeostasis of the joint, and subsequently stimulate the repair of damaged cartilage.

Inclusion Criteria:

• Patients aged 21-65 years
• both genders
• who will be diagnosed with stage 2-3 knee osteoarthritis according to the Kellgren-Lawrence Classification System (K-L) [10], with WOMAC Score > 2 for pain stiffness and physical disabilities
• having symptoms of Knee OA at least 3 months after getting usual conservative treatment like oral analgesics and Therapeutic Exercises.

Exclusion Criteria:

• Patient refusal.
• Patients who will be diagnosed with Stage 1or 4 OA according to K-L Classification
• History of knee trauma within the past month
• History of malignancies
• Any surgical intervention of the knee
• Local or systemic infection
• Any patient with sever renal Impairment
• Bleeding disorders

The data will be available upon reasonable request from the principal investigator

one year