Platelet-rich plasma therapy for knee joint problems: review of the literature, current practice and legal perspectives

to heal the injured tissue1,2). Its use is reported in the fields of dermatology, plastic surgery, dentistry, otolaryngology, urology, ophthalmology, and neurosurgery. In the fields of orthopedics and sports medicine, some clinicians have applied PRP therapy in acute ligament injury (medial collateral ligament rupture of knee joint, lateral collateral ligament rupture of ankle, etc.), chronic tendon problems (rotator cuff tear, lateral epicondylitis of elbow, tendinitis around the knee joint, Achilles tendinitis, plantar fasciitis, etc.), acute muscle rupture, or facilitation of bone healing after bone graft. Experimentally, it has also been applied in intraarticular injections for chondromalacia or osteoarthritis1-5). However, most clinical reports on PRP in orthopedics and sports medicine are case reports or case-series studies without a control group (evidence level IV), or do not have enough statistical significance due to their small sample size2). Since most growth factors are secreted within one hour after intraarticular PRP injection, PRP cannot alter the pathophysiology of chronic diseases such as osteoarthritis, and it is difficult to expect tha