Amniotic Suspension Allograft Injection for Knee Osteoarthritis

The Efficacy of Amniotic Suspension Allograft Injection in the Treatment of Knee Osteoarthritis: a Randomized Double-blind Controlled Trial

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.

According to statistics from the Ministry of Health and Welfare, the prevalence of knee osteoarthritis in Taiwan is approximately 15%. The main causes of the disease include overuse of joint cartilage and abnormal synovial fluid secretion, which impair joint mobility and cause symptoms like pain, swelling, and warmth. In severe cases, bone spurs and joint deformities can develop, further limiting mobility. Non-surgical treatment options for knee osteoarthritis currently include the use of braces, weight loss, lifestyle changes, oral pain relievers, and intra-articular injections, with only a small number of patients requiring surgery due to severe joint cartilage wear. In terms of injection treatments, given the limited efficacy of traditional corticosteroid and HA injections for knee osteoarthritis, an increasing number of physicians are using platelet-rich plasma (PRP) injections. Numerous clinical trials have supported this treatment option. However, the effectiveness of PRP treatment is partly dependent on the quality of the patient's blood. If the patient has poor blood quality (e.g., due to old age, multiple chronic diseases, autoimmune disorders, or use of anticoagulants), the efficacy of PRP injections will be significantly reduced.

Recently, a highly promising treatment option-placental-derived tissues-has begun to be used for knee osteoarthritis. Historically, placental-derived tissues have been applied to burns, ulcers, and other difficult-to-heal wounds such as corneal ulcers. More recently, these tissues have been applied in the orthopedic field. These products come in several formulations, some containing pulverized tissues (amniotic membrane, chorion, or both), cells from amniotic fluid, amniotic fluid itself, or a combination of these components. Placental tissues have been shown to contain a variety of anti-inflammatory cytokines, growth factors, and inhibitors, which are believed to reduce the inflammatory response associated with arthritis. Reducing this inflammation can not only alleviate the pain of knee osteoarthritis but also improve the quality of life for patients.

Inclusion Criteria:

1. Age between 18 and 80 years.
2. Body mass index (BMI) less than 40 kg/m².
3. Symptomatic knee osteoarthritis with X-ray evidence graded 2 or 3 on the Kellgren-Lawrence (KL) grading scale.
4. Numerical Rating Scale (NRS) score (scale 1 to 10) for pain greater than 4 over the past 7 days.
5. Able to walk independently or with the aid of a cane.

Exclusion Criteria:

1. Pregnant women or women planning pregnancy.
2. Regular use of anticoagulants.
3. Use of pain medications (except acetaminophen) within 15 days prior to injection.
4. History of substance abuse.
5. Patients who take additional knee symptom-relief medications during the study must report it to the research team; failure to comply will result in exclusion.
6. Corticosteroid or visco-supplementation injection into the affected knee within 3 months prior to enrollment.
7. Knee surgery on the affected side within 12 months before enrollment, or surgery on the contralateral knee within 6 months before enrollment.

9. History of organ or hematopoietic stem cell transplant. 11. Current use of immunosuppressive agents. 12. Diagnosis of cancer within the past 5 years (except for treated basal cell carcinoma).