Introduction – Understanding Knee Pain and Injection Options

Knee pain, especially due to osteoarthritis (OA), is a common condition that affects many people, impacting everyday activities and overall quality of life. As the cushioning cartilage in the knee wears down, pain and stiffness increase, making it difficult to move freely. For those looking to manage symptoms without surgery, injectable treatments have become popular alternatives. This article explores Arthrosamid — a newer knee injection — and compares it with more established options like hydrocortisone (steroid) and hyaluronic acid (HA) injections. Using up-to-date research, we’ll explain how these treatments work, their benefits, safety, and suitability, all in straightforward terms.

What Is Arthrosamid and How Does It Compare?

Arthrosamid is an injectable hydrogel made mostly of water combined with a polymer called polyacrylamide. When injected into the knee, it forms a gentle scaffold that sticks to the joint lining, creating a cushioning effect and helping to reduce inflammation. A recent review notes that Arthrosamid “adheres to and bulks up the synovial membrane and acts as a scaffold to treat the synovium” (Cole et al., 2022). In clinical practice, it is seen as “an effective, long-acting and safe non-surgical treatment that may delay knee surgery” (Bliddal et al., 2023).

By contrast, hydrocortisone injections are steroids that work by quickly calming inflammation inside the joint, providing rapid relief but typically for a shorter duration. Hyaluronic acid injections aim to restore the joint’s natural lubrication, improving movement and reducing pain by making the joint fluid thicker and more elastic.

To sum up, Arthrosamid offers structural support that cushions the joint over a longer period, steroids focus on fast but temporary anti-inflammatory effects, and hyaluronic acid works by improving joint fluid function.

How Effective Are These Injections and How Long Does Relief Last?

Arthrosamid’s benefits are supported by research showing its long-lasting effects. Studies reveal “statistically significant improvements at one year and even up to two years after injection” (Cole et al., 2022). In fact, a three-year follow-up study reported “clinically relevant and statistically significant decreases in pain and stiffness” (Bliddal et al., 2023), highlighting ongoing relief well beyond the short term.

In comparison, steroid injections provide quicker symptom relief—usually within days—but their effects tend to fade within weeks or a few months, making them suitable mostly for acute flare-ups. Hyaluronic acid injections give moderate relief, generally lasting three to six months as the joint fluid regains viscosity.

A recent study comparing these options found that Arthrosamid “outperformed steroids at six months but was comparable to hyaluronic acid,” while the differences between treatments became less clear after one year (Aykaç et al., 2025). So, for those seeking longer-lasting knee pain relief, Arthrosamid often shows a slight edge.

Imagine Jane, 65, whose knee pain improves briefly after a steroid injection but returns quickly. She next tries hyaluronic acid, gaining moderate relief for several months. After choosing Arthrosamid, her pain stays reduced for a year or more, allowing her to enjoy activities without frequent treatments.

Safety and How Often Can These Injections Be Repeated?

Safety is paramount when considering any treatment. Arthrosamid is well tolerated with minimal side effects; common issues might include slight swelling or brief discomfort near the injection site, which usually resolves quickly. Importantly, “no long-lasting adverse events have been reported following Arthrosamid injections” (Cole et al., 2022), and it remains effective and safe even three years after a single injection (Bliddal et al., 2023).

Steroid injections, while effective for quick relief, have potential drawbacks when used repeatedly, including possible damage to cartilage and joint weakening. Because of these risks, doctors typically limit their use to avoid harm.

Hyaluronic acid injections are generally safe for repeated courses every few months. Side effects are usually mild, such as short-term swelling or discomfort.

Overall, Arthrosamid’s longer-lasting effect means fewer injections over time with a low risk of side effects, which may suit many patients seeking convenience and safety.

Choosing the Right Injection: What Works Best and at What Cost?

Choosing the most suitable injection depends on individual factors such as age, severity of osteoarthritis, lifestyle, and prior treatments.

Arthrosamid is a good option for those wanting longer-term symptom control with fewer injections. It “seems to be an efficacious and safe treatment option for knee OA, providing benefits for at least two years” (Cole et al., 2022). However, it tends to be more expensive due to its advanced formulation.

Steroid injections remain useful for fast relief during painful flare-ups but are less suitable for ongoing management because of potential risks.

Hyaluronic acid is commonly recommended for mild to moderate arthritis when patients need to improve joint function over several months without steroids.

In the UK, Arthrosamid treatments are often self-funded, but payment plans help make it more affordable. Insurance cover is limited, so checking options beforehand is important.

Patients often ask, “Which is best for long-term knee osteoarthritis pain?” Current evidence suggests Arthrosamid offers the most sustained relief, though all treatments might play a role depending on individual needs and doctor advice.

Expert Care: Professor Paul Lee and MSK Doctors

Professor Paul Lee, a leading orthopaedic surgeon, and the MSK Doctors team have extensive experience managing knee osteoarthritis and advanced injection therapies. They focus on personalised, evidence-based guidance, helping patients understand all options to make informed decisions.

MSK Doctors were among the first in the UK to introduce Arthrosamid, successfully treating hundreds with careful protocols that maximise benefits and minimise risks. Their approach emphasises clear communication and ongoing support, ensuring patients receive trustworthy, unbiased care.

Summary: Making an Informed Choice

In summary, Arthrosamid, hydrocortisone, and hyaluronic acid injections each provide benefits for managing knee osteoarthritis. Arthrosamid offers longer-lasting pain relief with a low side-effect profile, steroids deliver quick but short-term benefits, and hyaluronic acid helps with joint lubrication and moderate-term symptom control.

Individual factors influence which treatment fits best. Consulting an expert healthcare professional specialising in musculoskeletal conditions ensures recommendations are tailored to you.

For personalised medical advice, always speak with a qualified healthcare professional.

References

• Cole, A., Maulana, R. K., Whitehead, J. P., & Lee, P. Y. F. (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
• Bliddal, H., Beier, J., Hartkopp, A., Conaghan, P. G., & Henriksen, M. (2023). Polyacrylamide hydrogel for the treatment of knee osteoarthritis: 3 year follow up results of a prospective clinical study. Annals of the Rheumatic Diseases. https://doi.org/10.1136/annrheumdis-2023-eular.6038
• 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(38), e44655. https://doi.org/10.1097/md.0000000000044655