GEKO

BACKGROUND:

Osteoarthritis of the knee is a painful condition. Early in the disease, patients often benefit from lifestyle changes and exercises. When the knee becomes very damaged, they may require knee replacement to alleviate the pain and improve symptoms. In between these stages, pain can be a major problem with non-surgical treatments, such as pain killers and physiotherapy, becoming less effective.

A new treatment has been developed which aims to relieve pain in the knee by the controlled blocking (embolisation) of small abnormal blood vessels around the knee. This seems to offer some benefit in early studies. A study is now needed to see if the treatment is effective at reducing pain in these patients. If it works, it could help a lot of people with knee osteoarthritis who are in a “treatment gap” between simple care and complex surgery.

Objectives:

1. In patients with painful knee osteoarthritis, is genicular artery embolisation effective at reducing pain at 6 months post-randomisation, compared to a placebo intervention?
2. To investigate the mechanism of genicular artery embolisation and its relationship to pain relief in patients with osteoarthritis using medical imaging.

Methods:

This clinical study is a randomised controlled clinical trial where patients are placed into one of two groups for treatment (at random) and the benefit obtained for each treatment group is compared. One treatment is the blood vessel blocking treatment (embolisation) and the other a “pretend” or placebo treatment that looks, feels and appears like the blood vessel blocking treatment, but does not actually block the blood vessels. Patients are not aware what treatment they are undergoing (known as a blinded study).

Two hundred and sixteen people with moderate knee osteoarthritis who have presented to secondary (hospital) care with knee osteoarthritis will take part. We will only include people who have tried the treatments recommended by NICE for standard care, and who have ongoing pain despite that.

Questionnaires assessing pain and function will be used to show if any difference exists between the treatments. We will ask people about their pain and function over a 12-month period after the treatment to decide which treatment is best. At the same time we will investigate what actually happens in the knee after the procedure by using imaging techniques to focus on why patients' pain is reduced.