Type of scan: MRI, Ultrasound or X Rays?

doctor examining type of scans

There seems to be some confusion amongst patients when it comes to understanding which type of scan is more appropriate for the investigation of different musculoskeletal conditions.

There are various ways to look inside our body. An Xray for instance is really indicated to assess the health of the bone as it uses a certain type of radiation that will highlight only dense structures like bones. A condition that is easily diagnosed with X Rays is osteo-arthritis which will show on the images as a degenerative and erosive process affecting the joint line. When there is suspicion that tissues other than bone might be the cause for the patient’s symptoms though, other scans might prove more appropriate in order to achieve a correct diagnosis. Here is when MRI and Ultrasound scan play an important role. But what are the benefits of using one or the other?

Advantages of an MRI scan

An MRI scan uses strong magnets to create a 3D picture of a large body part. A big advantage of this is that it allows one to have a look at the whole of a joint and also pick up details of deep body structures based on the assessment of the water content in them. So if, for instance, there has been a tear of a knee ligament the excess of fluid caused by the inflammation will be picked up as well as the extent of the ligamentous damage.

Ultrasound uses high frequency sound waves to hit the tissues and reproduce an image of them on a monitor in real time. This technique can only assess one small area at a time but the precision of the resolution is very high, being therefore very useful to assess local and superficial structures.

Advantages of an Ultrasound scan

One big advantage of Ultrasound scan in the musculoskeletal field is that it allows to assess a joint dynamically which can clarify the diagnosis of conditions such as bursitis or impingement syndrome of the shoulder. It can also be used for guided steroids injections for the treatment of such conditions with the advantage of not having to use any contrast dye.

Both MRI and Ultrasound are very safe procedures as they don’t use radiations. In most cases an MRI requires patients to lie inside a big tube for about 30/45 minutes whereas an Ultrasound is performed applying a small probe on the area to scan connected to a monitor.

Physiotherapists and osteopaths are trained to advise on appropriate diagnostic imaging and to refer you accordingly to a private diagnostic centre or back to your GP for NHS referral.


If you would like to understand more about which type of scan is more appropriate, our osteopaths and physiotherapists are all on hand to help and you can contact us on 020 7735 6813 or via email on info@kenningtonosteopaths.co.uk.