Clinicians use a variety of methods to help diagnose and test for osteoarthritis.

Physical Examination
This is the most common and cost effective method to examine a patient. Clinicians will review the patient's history, palpate the joint, observe any areas of swelling or tenderness, and perform range of motion tests to help make an assessment.

Radiographs (X-Rays)
Patients complaining of joint pain will often be requested to undergo and initial X-ray so the clinician can make observations of the joint space. Narrowing of the joint space because of the degeneration of the cartilage is obvious in an OA knee. This can also be a helpful tool to assess the progression of the disease.

Arthrography
This is a method of diagnosis in which a contrast media is injected into the joint space prior to an image being taken. It is helpful to detect meniscal injuries, loose bodies, and any other local changes within the joint. Magnetic Resonance Imaging (MRI) has replaced the majority of arthrography procedures.

Ultrasound
Although ultrasonic waves cannot readily pass through bone, this diagnostic tool can help evaluate soft tissue changes in and around the joint space.

Magnetic Resonance Imaging (MRI)
MRI images give the most comprehensive picture of what is occurring at the joint. This evaluation method allows for excellent contrast between all the different tissues of the knee. Clinicians can easily observe structural changes in both soft tissue and bone.

Arthrocentesis
Using a small needle, a clinician extracts a small amount of synovial fluid, the lubricating fluid in your knee, for analysis. Higher than normal concentrations of white blood cells, increased viscosity, cartilage fragments, or increased cytokines (a biochemical marker of tissue breakdown) can help to provide information in making a diagnosis.