Genicular Artery Embolisation for Knee Osteoarthritis II

Inclusion Criteria: ALL inclusion criteria below need to be fulfilled for the patient to participate in the study. * Participant is willing and able to give informed consent for participation in the study. * Participants aged 45 years or above. * Grade 1-3 knee OA on X-ray as per Kellgren-Lawrence Grading Scale * Knee pain for at least 3 months resistant to conservative non-surgical treatment (e.g., physiotherapy, steroid injections, weight loss programs, PRP (platelet-rich plasma) injections) * Be able to lie flat for at least 6 hours-this will be assessed by asking how participants sleep (bed, chair recumbent, semi-recumbent) and assessing what prevents them from lying flat overnight (breathlessness, back pain, etc) * Minimum score of 50 on baseline 0 - 100 VAS Exclusion Criteria: The patient may not enter the study if ANY of the following apply: * Rheumatoid arthritis or infectious arthritis * Severe knee OA (grade 4 on x-ray as per Kellgren-Lawrence Grade) * Renal impairment: eGFR \<45. Assessed from medical records or a blood test if required as is part of standard clinical practice when considering a patient for a therapeutic intervention. * Patients with a bleeding diathesis, or other bleeding risk such as patients on warfarin which cannot be stopped easily (e.g., patients with metallic heart valves) assessed by asking the patient and from medical records. Uncorrectable bleeding diathesis: INR\>1.6, Platelets \<50,000 * Requires oxygen on ambulation. Assessed by asking the patient and from medical records. * Low life expectancy (\<1 year) * Communication difficulty due to language barriers * Contraindication to MRI * Known allergies to barium sulfate, 3-aminopropyltrialkoxysilane, polyphosphazene or IV radiopaque contrast agent * History of Peripheral Arterial Disease (PAD) with intermittent claudication and/or rest pain * Pregnancy or positive pregnancy test (the participant will be exposed to ionising radiation during the fluoroscopy procedure) * Any other significant disease or disorder which, in the opinion of the recruiting physician, may put the participants at risk because of participation in the study, or may influence the result of the study or the participant's ability to participate