What's in an X-ray ?

What Does My X-ray Really Mean ?

Is there a ‘right’ time to get my joint imaged ?

It is often confusing for people to hear that X-ray imaging of your osteoarthritis is not always required in the first instance. It is possible for clinicians such as physiotherapists to diagnose osteoarthritis in the hip or knee from questions we ask you about your problem and from our physical examination. For many people it is surprising to know that even though your x-ray may demonstrate degenerative changes in the joint, there is not a good match between what you see on your x-ray and the amount of pain you have in your joint.

Facts and Myths About Imaging and Osteoarthritis

Should I get an X-ray ?

In the first instance when you present to your health professional such as a physiotherapist or GP, it is unlikely an x-ray is needed. It is not required to diagnose your osteoarthritis as experienced health professionals are able to do this from asking you some simple questions about your symptoms. There are guidelines that come from international organisations that can assist your health professional work out whether you need an x-ray to diagnose your osteoarthritis ( Refer to the UK organisation NICE for further information ).

Generally if you are over 45 years of age and have activity related pain (pain that comes on with movement ) with no morning stiffness in your joint or morning stiffness that eases within 30 minutes, it is not likely an x-ray is required in the first place. If your health professional is unsure about your diagnosis or you have other unusual symptoms, then imaging may be required.

Grading of Osteoarthritis On X-ray

How Do we See “Osteoarthritis “ on Your X-ray ?

The severity of your osteoarthritis may be reported on your x-ray. Osteoarthritis is graded in severity on an x-ray on a scale of 1-4.

Grade 1 Minimal or no osteoarthritis

Grade 2 Mild osteoarthritis

Grade 3 and 4 Moderate and severe osteoarthritis.

Moderate and severe osteoarthritis (Grade 3 and 4 ) is categorised by a progressive loss of your joint space and larger more prominent osteophytes ( or bony growths) and changes to the underlying bone. There have been many studies that show the severity of your x-ray is not a good predictor of your symptoms and should not be the only consideration for whether you require a joint replacement

Should I Get an MRI of my Joint Instead ?

There are recent studies that have looked at cartilage defects on MRI findings of knees and tried to work out whether this might be a better predictor of future joint replacement. An MRI does allow us to see your cartilage better then an x-ray. It has been suggested that full thickness cartilage loss (wearing down of the cartilage lining of your bones) which is able to be seen on MRI may be a better predictor of future knee replacement. A very recent study actually showed that a reduction of cartilage thickness in the knee joint only accounted for a small amount of worsening knee pain and that processes such as synovitis ( inflammation of the joint lining).

Despite these new study findings on MRI scans, it is still recommended that in the first instance you try all non-surgical or conservative treatments first. For those with mild osteoarthritis that is seen on an x-ray that DO NOT improve with initial conservative treatment such as exercise, weight loss and education may benefit from earlier MRI imaging. Whether you require an MRI or x-ray of your joint needs to be discussed with your health professional.