Aquamid Reconstruction for Osteoarthritis of the Knee

Osteoarthritis (OA) causes degradation and deformities of joints, including knees, hips, hands, and feet. Approximately more than 55% of populations above 45 years and more than 70% of population above 70 years will develop OA in at least one joint. The symptoms are dominated by pain but also stiffness and swelling occur. There is currently no cure for OA, and the ultimate treatment is joint replacement surgery. However, there is an unmet need to identify other treatment options that may delay or avoid surgery. Aquamid Reconstruction (AR) is a polyacrylamide hydrogel (PAAG) which is a non-degradable, highly visco-elastic synthetic gel, which is atoxic with durable effect and tissue-compatibility and well tolerated by mammal tissue by allowing in vivo vessel and fibrous in-growth. Experimental studies supported by histopathological observations have shown that AR exerts its effect via integration over time within the soft tissues, through a combination of vessel in-growth and molecular water exchange. Intra-articular injection of AR is expected to provide permanent pain relief and improve the functional ability through a cushioning or padding effect on the joint and thereby reduce symptoms and improve patients' quality of life. The purpose of this study is to obtain information of the safety and effectiveness of AR in patients with OA of the knee.

Intra-articular injection of 3 ml aquamid reconstruction (AR) to the knee. A second injection of 3 ml will take place after 1 month (+/- 2 weeks).

AR contains 2.5% polyacrylamide and 97.5% non-pyrogenic water, with a unique molecular structure that allows the normal water exchange with the surrounding tissue without losing shape or effect. AR is biocompatible, non-biodegradable, stable and sterile. The gel is provided in a sterile, pre-filled 1 ml sealed syringe. The gel is intended to be injected intra-articularly with a sterile 21G x 2 inch (0.8 x 50 mm) needle.

Change from baseline in the pain subscore of the Western Ontario and McMaster Universities Arthritis Index (WOMAC)

The WOMAC is a patient reported questionnaire that is easy to use and evaluates three domains; pain (five questions), stiffness (two questions) and physical function (17 questions), each weighted on a similar computation. The WOMAC Index is sensitive to change and is valid for elderly subjects with knee OA.

Change from baseline in all subscores of the Western Ontario and McMaster Universities Arthritis Index (WOMAC)

The WOMAC is a patient reported questionnaire that is easy to use and evaluates three domains; pain (five questions), stiffness (two questions) and physical function (17 questions), each weighted on a similar computation. The WOMAC Index is sensitive to change and is valid for elderly subjects with knee OA.

Participants will be surveyed about the current state of the treated knee. Predefined answers are: Worsened; No change; Improved; Cured.

Inclusion Criteria: Age > 18 years WOMAC pain score >/= 5 Kellgren and Lawrence radiographic scoring >/= 1 Signed informed consent form Exclusion Criteria: Other diseases affecting the joints such as rheumatoid arthritis Actual or recurrent infections requiring intravenous antibiotic treatment within the last 30 days or oral antibiotic treatment within the last 14 days before inclusion Less than 12 weeks since injection of HA or corticosteroids in study-knee joint before treatment Pregnancy or lactation Not able to comply with the requirements of the study Previous alloplasty