Understanding Medial-Compartment Knee Osteoarthritis and Inner-Knee Pain

Living with medial-compartment knee osteoarthritis (OA) often means coping with persistent inner-knee pain. This condition affects the inside area of the knee joint, where the thigh bone (femur) and shinbone ( tibia ) meet. Over time, the cartilage that cushions these bones wears away. As a result, bones start to rub together, leading to stiffness, swelling, and continual pain. Medial- compartment knee OA is very common, impacting nearly one in five people over the age of 45 in England. Ongoing inner- knee pain can make everyday tasks challenging and diminish quality of life, highlighting the need for effective, targeted treatments.

Many people with this condition also experience sensations of looseness or instability in the knee , which can make daily movements more difficult and further reduce confidence in their mobility.

How Arthrosamid Targets the Inner-Knee Joint: Mechanism of Action

Arthrosamid is a modern injectable therapy made from a gel called polyacrylamide hydrogel—97.5% water and 2.5% cross-linked polymer. This gel is carefully injected directly into the inner part of the knee joint , with ultrasound guidance used to make sure the treatment reaches the right spot. Inside the joint, Arthrosamid acts as an artificial cushion within the synovial cavity, restoring the natural thickness and slipperiness of the knee’s lubricating fluid. This helps reduce friction and absorb shocks during movement. By integrating with the joint lining, Arthrosamid creates a long-lasting buffer that supports the knee and relieves pain. The precise, ultrasound- guided injection means that Arthrosamid is delivered exactly where needed for optimal results in cases of inner- knee OA .

Research also shows that people with medial knee OA often subconsciously try to stabilize their knee by tensing surrounding muscles, but this can sometimes worsen joint pressure and discomfort.

Clinical Evidence: Efficacy and Safety of Arthrosamid

Scientific studies have found Arthrosamid to be both effective and safe for treating medial- compartment knee OA . Recent research has shown that Arthrosamid injections lead to significant improvement in knee pain and function, especially for people under 70 years old, with moderate OA (Kellgren-Lawrence grades 2 or 3) and a healthy body weight. Clinical trials have demonstrated that Arthrosamid provides better and longer-lasting pain relief compared to other injectable treatments such as hyaluronic acid and steroid injections—often for up to 12 months. Most side effects are mild and temporary, such as brief discomfort or swelling at the injection site. While more research is needed to fully understand which patients benefit the most, evidence shows that certain groups—especially older, non-diabetic patients with less severe OA—may see the greatest improvements. Overall, Arthrosamid is emerging as a promising option for managing stubborn inner-knee pain.

It's important to remember, however, that while stabilizing the knee to ease pain is important, trying to compensate by overusing knee muscles may increase joint pressure and, over time, could contribute to further wear and tear. A treatment that supports the joint itself, like Arthrosamid , helps address this issue directly.

Patient Selection and Administration Protocol

Arthrosamid is most suitable for people with medial-compartment knee osteoarthritis , especially those under 70, with a healthy body weight and OA severity at KL grades 2 or 3—particularly if symptoms have not improved with other treatments. Research suggests that older, non- diabetic patients with less advanced disease may benefit the most. The procedure is straightforward and usually completed during a single outpatient visit. The doctor numbs the area around the knee , provides antibiotics to minimize infection risk, and uses real-time ultrasound to guide the injection into the precise spot. This minimally invasive approach means you can go home the same day, and many patients feel relief soon after the procedure.

Supportive Expertise: Professor Paul Lee and MSK Doctors

Arthrosamid injections are performed by highly trained clinicians, such as Professor Paul Lee at MSK Doctors , who specializes in orthopaedics and rehabilitation. At MSK Doctors , patients can expect attentive, professional care in an environment that prioritizes recovery and well-being. Each patient’s treatment is tailored to their individual condition, ensuring responsible, expert guidance at every step.

Conclusion and Next Steps

Arthrosamid offers a modern, targeted approach for easing inner-knee pain caused by medial-compartment knee osteoarthritis . By restoring cushion and improving lubrication with just one minimally invasive injection , this treatment can offer lasting relief and help restore mobility. If ongoing inner- knee pain is disrupting your life, consider speaking to a specialist about whether Arthrosamid is right for you. Always seek personalized advice and treatment from a qualified healthcare professional.

References

Gao, H. C. K., Akhtar, M., Creedon, C., Nar, Ö. O., & Lee, P. Y. (2025). THE IMPACT OF PATIENT FACTORS ON THE MINIMAL CLINICALLY IMPORTANT DIFFERENCE OF ARTHROSAMID POLYACRYLAMIDE HYDROGEL INJECTION FOR KNEE OSTEOARTHRITIS: A COHORT STUDY. Journal of Osteoarthritis and Cartilage. https://doi.org/10.1016/j.joca.2025.02.648
Lewek, M. D., Ramsey, D. K., Snyder‐Mackler, L., & Rudolph, K. S. (2005). Knee stabilization in patients with medial compartment knee osteoarthritis. Arthritis & Rheumatism, 52(9), 2845-2853. https://doi.org/10.1002/art.21237