Patients develop osteoarthritis when the cartilage at the joints gets worn. This cartilage problem leads to weakening of nearby muscles and ligaments. Osteoarthritis causes pain, joint swelling and limited movement. MedlinePlus notes that almost everyone has signs of osteoarthritis by age 70, though it can start in middle age. Doctors use different tests as part of the diagnostic procedure.
Bone Imaging Tests
Physicians may request different imaging tests, which can show changes to the bones and joints. For example, the Mayo Clinic explains that doctors may have magnetic resonance imaging, or MRI, taken of the affected area of the body. An MRI uses a magnetic field and radio waves to produce images of both the bone and bone cartilage. Doctors use MRIs to determine the cause of pain.
Another imaging test used for osteoarthritis is an X-ray, which uses electromagnetic radiation to produce an image of the joint. An X-ray can show the breakdown of the cartilage as a narrowing space in the joint. X-rays also show bone spurs around the joint. MedlinePlus points out that in advanced cases of osteoarthritis, X-rays can show wear at the ends of the bone and bone spurs.
Physical Examinations
An important test for osteoarthritis is the physical examination, in which doctors look for signs of osteoarthritis. For example, MedlinePlus notes that doctors listen for cracking or grating sounds during joint movement. Doctors also look for joint swelling, in which the joints feel larger.
Patients with osteoarthritis have a limited range of movement and may complain that movement is painful. When doctors press the affected joint, patients may note that it feels tender.
Blood and Joint Fluid Tests
Physicians may take samples of certain bodily fluids to test for osteoarthritis. These laboratory tests may also rule out other causes of your joint pain. For example, MedlinePlus explains that blood tests do not diagnosis osteoarthritis. However, doctors can use the blood test to rule out other disorders that can cause joint pain, such as rheumatoid arthritis.
The Mayo Clinic adds that doctors may opt for a joint fluid analysis, in which they take a sample of fluid from the joint. This test shows if the joint is inflamed. The joint fluid analysis can also indicate if gout or an infection caused the inflammation.
