There have been few clinical trials on ASA for the treatment of knee osteoarthritis, and there is currently no literature reporting the optimal treatment dosage. Non-surgical treatment options include braces, weight loss, lifestyle changes, oral pain relievers, and intra-articular injections. Recently, placental-derived tissues have gradually been applied in the treatment of knee osteoarthritis. These tissues were initially used primarily for burns, ulcers, and wounds that are difficult to heal, but have now begun to be utilized in the orthopedic field. They have been proven to contain various anti-inflammatory cytokines and growth factors, which can reduce inflammation associated with arthritis. Reducing inflammation not only alleviates the pain of knee osteoarthritis but also improves patients' quality of life. The purpose of this study is to compare the therapeutic effects of amniotic suspension allograft (ASA), hyaluronic acid (HA), and saline on knee osteoarthritis and to examine whether there is a dose-response relationship with ASA injections.