Osteoarthritis (OA)is a painful and disabling disease, predicted to be the fourth largest cause of disability worldwide by 2020. It commonly affects the hip or knee ultimately resulting in total joint replacement. In order to assess disease progression and plan surgery, x-rays are taken as part of routine practice. However x-rays provide limited information about formation of substructures and changes occurring during progression of disease. The proposed study aims to invite patients with OA of the hip or knee to participate in detailed examinations of their pain and their painful joint through interviews, blood and urine samples taken, MRI magnetic resonance imaging)and donating their waste tissue after joint surgery (all of old joint). Informed patient consent will be sought in all cases.

The patient will be asked for permission for a clinician to access their notes for information relevant to the research, including full medical history, their sex and date of birth. Tissue obtained from joint replacement surgery at St. George's Hospital and transferred to St.George's, University of London where it will be prepared for various experiments including looking at the genes and proteins in people with osteoarthritis. The blood and urine samples will also be taken to St. George's, University of London, and prepared for studies on the genes and proteins in people with osteoarthritis. All samples provided will be anonymised with no patient details on the samples and stored in locked freezers, in locked labs. at St.George's, University of London.

Inclusion criteria:

Inclusion Criteria for OA patients:

Study participant will be recruited from rheumatology outpatient clinics and primary care:

1. fulfilling the American College of Rheumatology (ACR) criteria for the diagnosis of knee osteoarthritis
2. male or female,
3. symptomatic knee pain
4. on usual care for knee osteoarthritis including paracetamol and/or non-steroidal anti-inflammatory drugs
5. participants between 35 and 90 who will be undergoing knee replacement surgery or arthroscopy for osteoarthritis or knee surgery for fractured tibia/femur/fibula with osteoarthritis

Inclusion criteria for Early OA Patients

Study participant will be recruited from rheumatology outpatient clinics and primary care:

1. fulfilling the American College of Rheumatology (ACR) criteria for the diagnosis of knee osteoarthritis
2. male or female,
3. symptomatic knee pain
4. on usual care for knee osteoarthritis including paracetamol and/or non-steroidal anti-inflammatory drugs
5. Participants between 35 and 90 who have osteoarthritis but will not be undergoing knee surgery

Inclusion criteria for Healthy control subjects

1. Participants aged between 35 and 90 who do not have knee pain or osteoarthritis as a comparator group

People with symptomatic knee osteoarthritis who are in pain and are being considered for joint replacement surgery