So what is the difference between the two? Well simply put, sciatica occurs when there is pressing or pinching of the sciatic nerve which causes shooting pain radiating down one or both legs from the lower back. On the other hand, low back pain generally is considered more of an ache, and is often localised, meaning the pain normally sits in the one area.
Unfortunately, there is no recommended form of imaging (such as MRI's or ultrasounds) for sciatica. The reason for this is because sciatica is more of a symptom rather than an actual injury. Frequently, people who have no symptoms at all have disc bulges or other changes in their spine that sometimes cause sciatica. In addition to this, patients with symptoms common of sciatica have not had anything abnormal show up on an MRI .
Is that not the craziest concept? I think that's one of the main reasons why people get caught up in the sciatica diagnosis... because they can't find anything else to explain their pain!
So how do you know if you actually have sciatica?
Despite there being no specific imaging that can determine whether someone has sciatica, there are criteria and a number of manual movement tests that your treating health professional can use to determine whether your issue may be related to your sciatic nerve rather than just low back pain. The current criteria for sciatica is as follows:
In simpler terms, the criteria for sciatica is leg pain plus one of the following:
As mentioned, there is evidence that suggests that disc bulges or herniations may irritate sciatic nerve roots  however, this is not the only cause of sciatica. Even if the diagnosis is sciatica or lumbar (lower back) related pain due to a disc bulge, 60% of people are estimated to receive a good outcome within 3 months and 55-75% of people by 1 year . I know it sounds like a long time, but unfortunately this type of pain isn't something that can be dealt with overnight. The most important part of seeing improvement in your symptoms is being consistent with your treatment, and staying confident that it will pay off in the end. This is supported by a recent study which suggested that having a positive mindset about your symptoms may help you see improvements in your pain symptoms when used alongside appropriate treatment !
Take home message
Low back pain, and specifically sciatica, can be a very tricky thing to not only diagnose, but to also treat. The best course of action for you to take when you've got low back pain is to visit your local health professional, so that they can provide you with tailored advice, and determine what the best course of action is for your specific situation!
 Goldsmith, R., Williams, N. H., & Wood, F. (2019). Understanding sciatica: illness and treatment beliefs in a lumbar radicular pain population. A qualitative interview study. BJGP Open, 3(3), bjgpopen19X101654. https://doi.org/10.3399/bjgpopen19x101654
 Konstantinou, K., Dunn, K. M., Ogollah, R., Lewis, M., van der Windt, D., & Hay, E. M. (2018). Prognosis of sciatica and back-related leg pain in primary care: the ATLAS cohort. The Spine Journal, 18(6), 1030–1040. https://doi.org/10.1016/j.spinee.2017.10.071
 Stafford, M. A., Peng, P., & Hill, D. A. (2007). Sciatica: a review of history, epidemiology, pathogenesis, and the role of epidural steroid injection in management. British Journal of Anaesthesia, 99(4), 461–473. https://doi.org/10.1093/bja/aem238
 Stynes, S., Konstantinou, K., Ogollah, R., Hay, E. M., & Dunn, K. M. (2018). Clinical diagnostic model for sciatica developed in primary care patients with low back-related leg pain. PLOS ONE, 13(4), e0191852. https://doi.org/10.1371/journal.pone.0191852
Carly Rush - Exercise Physiologist