Moderate knee osteoarthritis (OA) affects millions of people, causing persistent pain and making everyday activities more difficult. One of the biggest challenges for those with moderate OA is finding ways to delay total knee replacement (TKR), which is often considered a last resort. Understandably, many people are interested in non-surgical treatments that can relieve symptoms and help maintain an active lifestyle. Arthrosamid , a new injection treatment made from a gel called polyacrylamide hydrogel , is receiving attention as a promising option for delaying knee replacement in moderate OA. At MSK Doctors , under the guidance of Professor Paul Lee, patients have access to experienced care and support throughout their treatment and recovery.

How Does Arthrosamid Work?

Arthrosamid is a sterile, long-lasting gel composed of polyacrylamide. It's injected directly into the synovial cavity—the space within the knee joint that contains lubricating fluid. Once in place, the gel integrates with the synovial membrane (the joint lining), restoring the thickness and slipperiness of the natural fluid. This extra cushioning reduces friction between the bones, eases pain, and helps the knee move more smoothly. Research shows that Arthrosamid has a strong safety record, making it a reliable option for those seeking relief from knee OA symptoms.

What Does the Clinical Evidence Say?

Arthrosamid ’s effectiveness has been tested in several clinical studies. In a key randomized controlled trial, it was compared to traditional hyaluronic acid injections over the course of a year. Overall, Arthrosamid performed just as well, and in certain groups—such as younger patients, people with a healthy body weight, and those with moderate OA—it worked even better. Patients noticed less pain and greater comfort within three to six months of treatment, and these benefits often lasted a year or longer. Encouragingly, follow-up studies for up to three years showed that pain relief continued without serious side effects.

Further studies suggest that Arthrosamid provides noticeable symptom relief, especially for older patients with moderate (rather than severe) OA and without complicating health issues such as diabetes . However, it’s important to remember that while Arthrosamid can delay the need for knee surgery for many patients, it does not cure osteoarthritis .

When considering injectable therapies more broadly, a large study comparing different types of hyaluronic acid found no significant differences in delaying surgery between them. This highlights the importance of choosing the right treatment for each patient, rather than relying on a one-size-fits-all approach.

Who Is the Right Candidate for Arthrosamid?

Selecting the right patients is crucial for successful outcomes with Arthrosamid . The best candidates are usually adults with moderate knee OA (classified as Kellgren-Lawrence grades 2 or 3), under the age of 70, and with a healthy body mass index (BMI). Those with advanced OA (grade 4) or with certain health conditions may not experience as much benefit from the treatment. Arthrosamid is not suitable for patients with active joint infections or previous non-absorbable implants in the knee.

Before and after the injection, patients can usually continue their standard pain relief medications, but should avoid systemic corticosteroids as they may interfere with recovery. To get the best results, a personalized rehabilitation program is essential—helping patients regain strength , flexibility, and confidence in their knee.

Bringing Arthrosamid Into Everyday Practice

Arthrosamid injections are performed in an outpatient setting under local anaesthetic, so patients can return home the same day. Most people experience only mild, short-term effects such as slight pain or swelling, and long-term complications are rare. After the injection, a tailored physiotherapy plan helps restore knee movement and build strength.

At MSK Doctors , patients receive care in a professional and supportive environment. Professor Paul Lee and his multidisciplinary team offer both expert clinical oversight and attentive follow-up, ensuring patient safety and monitoring recovery. As with any medical procedure , ongoing check-ups are important so any changes can be addressed promptly.

Conclusion

Arthrosamid provides a safe and effective non-surgical option for many people with moderate knee osteoarthritis , helping to delay the need for knee replacement surgery . Careful patient selection and appropriate rehabilitation maximize the chances of success. While Arthrosamid can provide significant relief, it’s important to remember that individual responses vary, and knee replacement may still be necessary for some. For advice tailored to your needs, speak with a qualified healthcare provider.