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.
