Intra-Articular Polyacrylamide Hydrogel Injections Improve Pain and Function in Knee Osteoarthritis (HYDRO-KNEE)

Feza Korkusuz MD

Status: Completed

Conditions: Osteoarthritis; Osteoarthritis of the Knee; Degenerative Joint Disease of the Knee; Knee Osteoarthritis

Treatments: Biological: Polyacrylamide hydrogel 2.5% intra-articular injection

Study type: Observational

Funder types: Other

Identifiers

NCT07193368

Approval No: 2025-14/3

Details and patient eligibility

About

This study is designed to evaluate the effects of intra-articular injections of polyacrylamide hydrogel (Arthrosamid®) in patients with knee osteoarthritis. A total of 387 patients (593 knees) were treated across three medical centers in Türkiye.

The purpose of the study is to determine whether this injection can reduce knee pain and improve physical function in everyday life. Pain is being measured using a Visual Analogue Scale (VAS), and function is being assessed with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).

Enrollment: 387 patients

Sex: All

Ages: 40+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age ≥ 40 years
• Radiographic diagnosis of knee osteoarthritis (Kellgren-Lawrence grade 2-4)
• Received intra-articular 2.5% polyacrylamide hydrogel injection

Exclusion criteria

• Prior knee surgery before PAAG injection
• Malignancy, local infection, or septic arthritis
• Inflammatory joint disease (e.g., rheumatoid arthritis)
• Pregnancy
• Avascular necrosis
• Advanced varus or valgus knee deformity

Trial design

387 participants in 1 patient group

Knee Osteoarthritis Patients

Description:

Patients diagnosed with knee osteoarthritis (Kellgren-Lawrence grade 2-4) who received a single intra-articular injection of 2.5% polyacrylamide hydrogel (Arthrosamid®, Contura, Denmark). Followed retrospectively for 12 months to assess pain (VAS) and function (WOMAC).

Treatment:

Biological: Polyacrylamide hydrogel 2.5% intra-articular injection