Do I Need a Scan?
Do I Need a Scan?
Swipe through the images and read below for the answer!
Scans Rarely Show the Cause
While scans are fantastic for ruling out the most serious pathological conditions that require medical treatment, they are often over-used in the management of low back pain.
Serious pathology accounts for less than 1% of acute low back pain and is often accompanied with many identifiable red flags in a patient’s history that indicate that something more sinister may be going on.
Studies estimate that 95% of acute low back pain cases are benign and actually have no diagnosis based on scan (X-ray, MRI, CT).
Only around 5% of acute low back pain cases have a scan finding, such as significant disc herniation with nerve root impingement, that can confidently be attributed as the primary cause of their pain and disability.
Most Findings are Normal
The vast majority of ‘findings’ on a scan are normal age-related changes that are poorly associated with pain and disability.
Many studies looking at MRI scans in asymptomatic individuals show a large portion have evidence of disc degeneration, disc bulging, severe cartilage lesions and tears without any pain or disability at all – even in those as young as 20 years old!
It is worth noting however, that studies show those with back pain did have a higher prevalence of disc degeneration on MRI scan than those without back pain.
The takeaway from these studies is that while abnormalities on scans are not completely irrelevant, these changes often are not sufficient to cause pain; and in most cases do not need to be corrected to get out of pain.
Scan Findings Change
Images are a snap-shot in time. They can quickly become outdated due to the body’s amazing capacity to heal.
Studies looking at disc herniations found that around 66% had regressed or resolved on follow up scans after conservative management – with the most severe disc injuries showing the highest rates of healing.
Reliability of Scans
Imaging technology has come a long way; and depending on your budget you are able to have incredibly sensitive and detailed images of your body taken – particularly with MRI scans, often considered the gold standard of imaging.
Despite the precision of scanning technology, images are only as good as those interpreting them!
A study reported the various findings of 1 patient receiving 10 MRI scans at 10 different radiology clinics in the span of 3 weeks:
49 different findings
16 findings were unique (only reported in 1 of the 10 scans)
0 findings reported consistently across all 10 scans
Each radiologist averaged 12 errors
Besides the burgeoning cost on the medical system that we all pay for, these highly sensitive images can in some cases be detrimental to a patient’s recovery.
In trying to identify the 1% of serious pathology, imaging brings to a patient’s attention a whole bunch of nasty sounding and not-so-nice looking but NORMAL age-related changes in their body that can easily be misunderstood as the sole reason for their pain.
This misunderstanding can have a powerful effect on a person’s perception of their body and their behaviour. They can easily become anxious and worried, start adopting rigid protective postures, avoiding movement/activity that is good for them and developing muscle guarding that further stresses pain sensitive structures – in an unhelpful attempt to protect what they believe to be a ‘damaged’ back.
Another unfortunate side effect of this can be seen clearly in a study which reported that patients who received an MRI for low back pain within the first month had an 8x greater risk of undergoing surgery and 5x more medical costs than those that did not – in an attempt to treat to scan findings that possibly had little relevance to their injury onset or recovery.
When to Scan?
From your history, your health care provider will determine whether a scan is necessary to rule out a more serious underlying pathology.
Indications for a scan:
– When fracture, cancer, infection, an inflammatory disorder or severe nerve compression are suspected
– When there is severe pain and neurological deficit that is progressively worsening
– When severe pain and neurological deficit has failed to improve after >6 weeks of conservative care
Written by: David Resic (Osteopath)
Brinjikji, W, Diehn, F, Jarvik, J, Carr, C, Kallmes, D, Murad, M, Luetmer, P, (2015). MRI Findings of Disc Degeneration are More Prevalent in Adults with Low Back Pain than in Asymptomatic Controls: A Systematic Review and Meta-Analysis. AJNR AM J Neuroradiol
Brinjikji W, Luetmer PH, Comstock B, et al, (2015). Systematic literature review of imaging features of spinal degeneration in asymptomatic populations. AJNR Am J Neuroradiol
Chiu et al, (2015). The probability of spontaneous regression of lumbar herniated disc: a systematic review, Clin Rehabil
Herzog R, Elgort DR, Flanders AE, Moley PJ, (2017). Variability in diagnostic error rates of 10 MRI centers performing lumbar spine MRI examinations on the same patient within a 3-week period. Spine J.
Lateef, H., & Patel, D. (2009). What is the role of imaging in acute low back pain? Current Reviews In Musculoskeletal Medicine
Wáng YXJ, Wu AM, Ruiz Santiago F, Nogueira-Barbosa MH, (2018). Informed appropriate imaging for low back pain management: A narrative review. J Orthop Translat.
Zhong et al, (2017). Incidence of Spontaneous Resorption of Lumbar Disc Herniation: A Meta-Analysis, Pain Physician