Long-Term Relief from Knee Osteoarthritis: How a Single Polyacrylamide Hydrogel Injection Can Help Over 24 Months

Introduction

Knee osteoarthritis (OA) is a widespread, persistent condition that slowly wears away the cartilage in the knee joint . This leads to ongoing pain and can significantly limit mobility. For many people, finding long-term relief is a real challenge, and current treatments often fall short. Recently, polyacrylamide hydrogel (PAAG) injections have emerged as a promising new option. In this article, we’ll explore how just one PAAG injection can reduce knee pain and improve movement for up to two years, offering renewed hope for those coping with OA.

What Are PAAG Injections—and How Are They Different?

Polyacrylamide hydrogel is a soft, gel-like material designed to cushion and lubricate the inside of the knee joint . When injected, it helps reduce friction and discomfort in areas damaged by OA. Unlike common treatments such as steroid or hyaluronic acid injections —which may only provide relief for a few months—PAAG remains in the joint and works for much longer.

Doctors use a tool called the Visual Analogue Scale (VAS) to measure pain levels over time. Studies have found that patients who receive PAAG injections experience a steady decline in pain that lasts many months. This ongoing improvement distinguishes PAAG from other, shorter- acting knee injections .

The Study: Who Participated and What Was Measured?

These results come from a 24-month study conducted at multiple clinics in the UK. Researchers enrolled people with knee OA who varied in age, body weight (measured by BMI), and the severity of their arthritis. This approach made the results more applicable for a wide range of patients.

To measure the treatment's impact, patients regularly completed questionnaires about their pain and knee function , including the Oxford Knee Score and the Lysholm score. An important measurement in this study was the "minimally clinical important difference" (MCID)—which simply means the smallest change in symptoms that genuinely makes a difference to patients.

The study found that certain factors improved the chances of significant pain and function improvement over 24 months, including older age, lower severity of arthritis , absence of diabetes, and having OA in both knees rather than just one.

What Was the 24-Month Outcome of PAAG Injections?

Over two years after a single PAAG injection , patients reported clear, lasting reductions in knee pain. Many noticed relief within weeks, which improved over several months and then remained steady—often without the need for additional injections.

This long-lasting effect sets PAAG apart from many other treatments, which may require frequent repeat injections as symptoms return. Most patients experienced no or only minor side effects, and any complications that did arise were generally mild and manageable.

Overall, the 24-month results suggest that PAAG injections can offer durable pain relief and improved knee function—providing a practical, low-maintenance treatment option for people with knee OA.

What Does This Mean for the Future of Knee Osteoarthritis Care?

In summary, a single polyacrylamide hydrogel injection has the potential to deliver significant, long-term relief from knee OA pain . The most favorable results were seen in older adults, those without diabetes , and those with less severe arthritis , highlighting the need for personalized treatment.

These findings could reshape how doctors manage knee OA , possibly reducing reliance on frequent injections or more invasive procedures like surgery. As with all new treatments, more research will help fine-tune which patients are most likely to benefit.

Looking ahead, PAAG injections represent a promising advancement in OA care—helping people regain mobility and improve their quality of life for years to come.