Do I need an X-ray?
X-ray imaging is the most well known type of investigation for problems affecting the skeletal system. So a common question we encounter as physiotherapists is “do I need an X-ray?”
X-rays are ideal for spotting fractures, dislocations, misalignments and narrowed joint spaces but an X-ray won’t show subtle bone injuries or soft tissue injuries. And the vast majority of injuries we see as physiotherapists involve soft tissues (e.g. muscles, tendons, cartilage and nerves) and none of these structures can be visualised on X-ray. Lots of musculoskeletal conditions can cause inflammation and unfortunately X-rays cannot show this either. Whilst there are some specific reasons to get an X-ray it should not be regarded as the ‘go to’ investigation for all problems. Your physiotherapist or doctor will be able to guide you depending upon your injury.
One of the reasons why clinicians are reluctant to refer for X-rays is found in its name. The picture that is produced is created by firing X-rays into the body – and X-ray is a type of ionising radiation. Now before you get too alarmed, the amount of radiation is incredibly small.
For example, an X-ray of your chest or limbs is equivalent to a few days’ worth of background radiation and has less than a 1 in 1,000,000 chance of causing cancer. More information can be found at the UK.GOV website.
The other main reason is that for many conditions affecting your spine, joints and soft tissues there are better and more advanced imaging techniques like ultrasound, MRI and CT scans. These scans provide very detailed and more clinically useful information. However X-rays do have their place as waiting times for X-rays are generally low, your GP can usually refer you and the procedure itself is comparatively cheap.
Overall, unless you have a very specific injury or presentation, it is unlikely that you will need an X-ray. Indeed, even if you had one, it wouldn’t help in your management a great deal. Also, sometimes an X-ray or MRI can highlight anomalies that are ‘red herrings’ and not causing the pain and this can muddy the waters and create further anxiety for the patient.
Because X-rays have often been over-used in the past, a team of clinicians set out to define the conditions in which an X-ray should be used in relation to possible fractures affecting the ankle called The Ottowa Ankle Rules. This has proven to be a very effective guide. Unfortunately we don’t have such clear guidelines to assist with ordering X-rays elsewhere.
So we’ve talked about when it is best to have an X-ray as well as highlighting their limitations. Perhaps a better question to ask is ‘What Type of Imaging Do I Need?’