Introduction

Knee osteoarthritis (OA) is a common condition where the cartilage cushioning the knee gradually wears away, causing pain, stiffness, and difficulty moving. It affects many older adults and can significantly impact daily life. As new non-surgical treatments become available, patients understandably want to know if these options are safe, especially over the long term. One such treatment gaining attention is Arthrosamid, a hydrogel injection used to ease symptoms and improve joint function. This article provides a clear, evidence-based look at Arthrosamid’s safety, drawing on the latest research and expert insights.

What Are Arthrosamid Injections and How Do They Work?

Arthrosamid is a gel-like substance made from 2.5% cross-linked polyacrylamide mixed with water. When injected into the knee joint, it stays there permanently, acting as a cushion and supporting the joint’s natural structure. As one review explains, “It adheres to and bulks up the synovial membrane and acts as a scaffold to treat the synovium.” This sets Arthrosamid apart from steroids or hyaluronic acid injections, which are gradually absorbed by the body. Using Arthrosamid requires skill and careful patient evaluation to ensure the best results. Leading specialists, including Professor Paul Lee – an orthopaedic surgeon with extensive experience in cartilage treatments – and teams at centres like MSK Doctors, apply rigorous standards to provide safe, personalised care.

Reviewing the Long-Term Safety of Arthrosamid: Evidence and Patient Outcomes

A key question for anyone considering Arthrosamid is its long-term safety. Research to date is reassuring. A systematic review found that, “Injection of PAAG hydrogel intraarticularly into the knee has been shown to be safe with no long-lasting adverse events reported.” Most patients experience mild side effects shortly after treatment, such as some swelling or stiffness, with serious complications being very rare. Another study tracking patients for up to a year noted “no significance at 12 months” in terms of safety concerns, indicating stable outcomes over this period. There are even follow-up data showing “statistically significant results at 2 years,” demonstrating sustained benefits without new risks. Laboratory research also supports Arthrosamid’s safety at a cellular level. Testing found that “at the tested concentrations and timepoints, the 2.5 iPAAG had no statistically significant effects on cell survival, non-apoptotic and apoptotic cell death, or the neurite network area,” meaning it does not harm nerve cells in vitro. Importantly, no evidence links Arthrosamid to damage of cartilage or bone within the joint.

Arthrosamid Versus Steroid Injections: Safety and Effectiveness in Perspective

Steroid injections have long been used to reduce inflammation and pain in knee OA, providing quick relief. However, repeated steroid use can lead to concerns such as potential cartilage damage and reduced effectiveness over time. When compared directly, studies show Arthrosamid offers some benefits. One found that “iPAAG outperformed Steroid at 6 months… [but showed] no significance at 12 months,” suggesting a modest advantage in the mid-term. Additionally, “iPAAG showed the highest patient acceptable symptom state rates (72%, 54%, and 42% at 3, 6, and 12 months),” meaning more patients felt their symptoms were well controlled with Arthrosamid in the short to medium term. That said, the same study notes “long-term superiority is limited,” highlighting the importance of realistic expectations and individualised treatment plans. Compared to hyaluronic acid injections, Arthrosamid demonstrated “numerically superior data” in some randomised trials, indicating favourable outcomes but not overwhelming superiority. British orthopaedic guidelines recommend careful use of steroid injections, mindful of their limitations. Arthrosamid’s hydrogel offers a longer-lasting option without the same concerns about joint damage, which is taken into account at specialist centres such as MSK Doctors. It’s worth noting that patients undergoing certain procedures for trauma or cancer involving bone implants follow different treatment protocols and are not candidates for Arthrosamid. Orthopaedic professionals in the UK continue to support innovations like Arthrosamid where evidence justifies their use, backed by respected bodies including the British Orthopaedic Association and the British Knee Society.

Guidance for Patients Considering Arthrosamid Injections

If you are thinking about Arthrosamid injections, it’s important to have an open conversation with your healthcare provider. Ask about their experience with Arthrosamid, what you can realistically expect, potential side effects, and how your joint health will be monitored over time. Shared decision-making is key: understanding both advantages and risks helps you make an informed choice. Clinics with specialist cartilage expertise, led by experienced surgeons like Professor Paul Lee, offer the best support to navigate the options safely and effectively. Remember, knee osteoarthritis management is highly individual. Choosing evidence-based, patient-centred care aligned with your needs offers the greatest chance of success.

Conclusion

To sum up, current research and clinical practice provide reassuring evidence that Arthrosamid injections have a positive long-term safety profile when used appropriately in knee osteoarthritis. As highlighted by experts, “this PAAG hydrogel seems to be an efficacious and safe treatment option for knee OA and provides positive results for at least 2 years.” Staying informed, seeking advice from trusted specialists, and following recommended guidelines are essential to making the best decisions for your knee health.

References

• Cole, A., Maulana, R., Whitehead, J., & Lee, P. (2022). A Systematic Review of the Novel Compound Arthrosamid Polyacrylamide (PAAG) Hydrogel for Treatment of Knee Osteoarthritis. Medical Research Archives, 10(8). https://doi.org/10.18103/mra.v10i8.2950
• Aykaç, B., Dinç, M., Nar, Ö. O., Karasu, R., & Bayrak, H. Ç. (2025). Comparative efficacy of polyacrylamide hydrogel versus hyaluronic acid and corticosteroids in knee osteoarthritis: A retrospective cohort study. Medicine, 104(15), e44655. https://doi.org/10.1097/MD.0000000000044655
• Walmod, P. S., Kusk, P., Jøhnk, N., Ankorina-Stark, I., & Essex, A. (2025). An injectable 2.5% cross-linked polyacrylamide hydrogel (2.5 iPAAG) demonstrates no neurotoxicity in human induced pluripotent stem cells-derived iCell® GlutaNeurons. Frontiers in Toxicology. https://doi.org/10.3389/ftox.2025.1585430