Ask Congress To Make Your Falls Risk Assessment A Medicare-Covered Benefit!

Learn More

Physical Therapy Can Address the Challenges of Medical Imaging and False Positives for Musculoskeletal Conditions

As a physical therapist for over 14 years, it’s weekly that I encounter a patient wanting an MRI. From the perspective of the patient, imaging seems the obvious best course of action to determine their diagnosis and guide subsequent interventions. I’ve also routinely seen patients frustrated with insurance companies who refuse to authorize advanced medical imaging like MRIs without first trialing physical therapy. These patients often arrive for their evaluation despondent, as they assume physical therapy will be ineffective since there is no imaging to guide the therapist’s intervention.
It’s with caution and care that we as therapists must educate patients regarding some of the pitfalls of medical imaging, while attempting to build trust that a thorough physical exam is often more clinically effective at ruling in or out certain diagnoses.
We’ll explore some of the challenges with utilizing medical imaging for musculoskeletal conditions as well as highlight the effectiveness of the physical therapists’ musculoskeletal exam.

Medical Imaging

To be clear, medical imaging technologies such as Magnetic Resonance Imaging (MRI), Computed Tomography (CT) scans, and X-rays can serve as invaluable tools in the diagnosis of musculoskeletal disorders. These technologies allow clinicians to visualize the internal structures of the body and detect abnormalities that might explain a patient’s symptoms.
However, not all abnormalities found in imaging correlate with the patient’s pain or functional limitations. In fact, medical imaging often reveals structural changes or degenerative features in asymptomatic individuals. This phenomenon can lead to false positives, where findings on imaging suggest a problem that is actually not the cause of the patient’s symptoms. These false positives can create diagnostic dilemmas, leading to unnecessary treatments, surgeries, or interventions that ultimately do not address the true source of the patient’s symptoms.

Imaging Findings in Asymptomatic Populations

A growing body of research has demonstrated that musculoskeletal imaging findings are relatively common in asymptomatic populations. These findings challenge the notion that every abnormality seen on an MRI, CT scan, or X-ray is clinically significant. In the studies listed below, we’ll explore some commonly seen imaging findings…and how often they occur in asymptomatic populations.

1. MRI and Degenerative Disc Disease

MRI is frequently used to assess the spine, particularly in patients with complaints of low back pain. One of the most common findings is degenerative disc disease, which can include disc bulges, disc protrusions, and herniations.
However, studies have shown that these findings are prevalent in asymptomatic individuals. A study published in the American Journal of Neuroradiology found that 37% of asymptomatic individuals under the age of 40 had disc degeneration on MRI, and this number increased to 96% in individuals over 80 years old.
Furthermore, 30% of asymptomatic people in their 20s had disc bulges, and this percentage increased with age up to 84% of 80-year old.1 These findings indicate that degenerative changes are simply a part of the normal aging process and do not necessarily correlate with pain or dysfunction.

2. MRIs and Osteoarthritis

While certainly not the preferred method to evaluate knee OA, it’s worth highlighting that a 2012 study examined the prevalence of positive findings on MRI. In this study, 710 participants (some with knee pain and some without knee pain) were given MRIs of the knee. Prevalence of any abnormality (which included osteophytes, cartilage damage, and bone marrow lesions) was 89%. The study went further to highlight that “the higher the age, the higher the prevalence of all types of abnormalities detectable by MRI.” Last but not least, the prevalence of at least one type of pathology was ~87% of painless knees.2 This highlights the disconnect between imaging findings and clinical symptoms in many cases of knee pain.

3. Imaging and Rotator Cuff Tears

Patients with shoulder pain often assume the worst: a rotator cuff tear. We’ve all seen the individual wearing the big, bulky brace with their arm strapped to their side following rotator cuff repair. These patients are often in therapy for months as treatment focuses on maintaining/improving ROM and gradually strengthening the shoulder. But how common are rotator cuff tears? Several studies show they are relatively common in the population3,4 (approximately 22%). Of those with tears, studies confirm that 50 to 65% of those patients experienced no symptoms. In fact, one study even highlighted that “asymptomatic tear was twice as common as symptomatic tear.”3

4. MRI and Labral Tears

MRI is often used to assess hip pain, particularly in younger populations with suspected labral tears. Labral tears are frequently found in athletes and active individuals and are thought to be a source of hip pain. However, labral tears are also common in asymptomatic individuals. One study examined ~100 young athletes with no hip symptoms and found that 89% of those older than 16 had experienced a labral tear.5 These findings suggests that labral tears may be a normal part of an active lifestyle and not necessarily a cause of pain.

Interpretation Variability

To complicate matters further, radiologist interpretation of imaging findings can vary wildly. One study examined what happened when 1 patient (a 63-year-old woman with low back pain and L5 radicular symptoms) went to 10 different MRI centers for imaging over a 3-week period. The result: “This study found marked variability in the reported interpretive findings and a high prevalence of interpretive errors in radiologists’ reports of an MRI examination of the lumbar spine performed on the same patient at 10 different MRI centers over a short time period. As a result, the authors conclude that where a patient obtains his or her MRI examination and which radiologist interprets the examination may have a direct impact on radiological diagnosis, subsequent choice of treatment, and clinical outcome.”6

History and Physical Exam

Considering the high prevalence of false positives, along with interpretation variability between radiologists, what should a patient do to ensure they are properly addressing their musculoskeletal pain? Leverage the expertise of physical therapists!
Physical therapists are in a prime position to perform a thorough history and physical exam. Based on the findings from this in-person assessment, therapists can formulate a clinical hypothesis, and begin to intervene to address the true source of the patient’s symptoms. It’s very common that physical therapists are capable of isolating the source of symptoms during the evaluation. Treatment can then be performed to address the tissue responsible for the symptoms.
This can provide relief as early as the first visit. Not only does this have positive implications for patient buy-in, but it often calms the patient’s concerns that imaging may be needed. This can have profound implications for reducing the overall costs associated with a musculoskeletal injury, as well as reducing the need for more invasive and expensive interventions.

Imaging and Worker’s Compensation

As highlighted above, imaging has been shown to have a high false positive rate. So, what happens in cases where imaging is applied early during a worker’s compensation claim? A 2013 study highlighted that early imaging for low back pain, regardless of radiculopathy status, significantly increased costs associated with each claim.7
Furthermore, the authors of the study went further to highlight that “Providers and patients should be made aware that when early MRI is not indicated, it provides no benefits, and worse outcomes are likely.” Another study, published in the prestigious journal The Lancet highlighted similar findings, “Lumbar imaging for low-back pain without indications of serious underlying conditions does not improve clinical outcomes. Therefore, clinicians should refrain from routine, immediate lumbar imaging in patients with acute or subacute low-back pain and without features suggesting a serious underlying condition.”8

Conclusion

The widespread use of medical imaging technologies has transformed the diagnosis and treatment of musculoskeletal disorders. However, it has also led to the discovery of numerous imaging abnormalities in asymptomatic individuals, raising concerns about false positives and their potential impact on patient care.
Findings such as disc degeneration, osteoarthritis, rotator cuff tears, and labral tears are common in individuals who experience no pain or functional limitations, highlighting the need for a cautious approach to interpreting imaging results.
Healthcare providers must recognize that imaging findings do not always correlate with symptoms and should prioritize a comprehensive clinical assessment when diagnosing musculoskeletal disorders. By focusing on the patient’s history, physical examination, and functional abilities, providers can avoid overreliance on imaging results and reduce the risk of unnecessary treatments, all while improving outcomes and minimizing costs.
To learn more about how Upstream Rehabilitation and our family of brands can assist with Workers’ Compensation and how physical therapy plays an effective role in helping injured workers return to work, contact our Workers’ Compensation team today!

 

References

  1. Brinjikji, W., Luetmer, P. H., Comstock, B., Bresnahan, B. W., Chen, L. E., Deyo, R. A., … & Kallmes, D. F. (2015). Systematic literature review of imaging features of spinal degeneration in asymptomatic populations. American Journal of Neuroradiology, 36(4), 811-816.
  2. Guermazi, A., Niu, J., Hayashi, D., Roemer, F. W., Englund, M., Neogi, T., … & Felson, D. T. (2012). Prevalence of abnormalities in knees detected by MRI in adults without knee osteoarthritis: population-based observational study (Framingham Osteoarthritis Study). BMJ, 345, e5339.
  3. Minagawa H, Yamamoto N, Abe H, et al. Prevalence of symptomatic and asymptomatic rotator cuff tears in the general population: From mass-screening in one village. J Orthop. 2013;10(1):8-12. Published 2013 Feb 26. doi:10.1016/j.jor.2013.01.008
  4. Hinsley H, Ganderton C, Arden N, Carr A. (2022) Prevalence of rotator cuff tendon tears and symptoms in a Chingford general population cohort, and the resultant impact on UK health services: a cross-sectional observational study. BMJ
  5. Briggs K, Philippon M, Ho C, McNamara S (2017). Prevalence of acetabular labral tears in asymptomatic young athletes. British Journal of Sports Medicine.
  6. Herzog, R., Elgort, D. R., Flanders, A. E., & Moley, P. J. (2017). Variability in diagnostic error rates of 10 MRI centers performing lumbar spine MRI exams on the same patient within a 3-week period. The Spine Journal, 17(4), 554-561.
  7. Webster BS, Bauer AZ, Choi Y, Cifuentes M, Pransky GS. Iatrogenic consequences of early magnetic resonance imaging in acute, work-related, disabling low back pain. Spine (2013) Oct 15;38(22):1939-46. doi: 10.1097/BRS.0b013e3182a42eb6. PMID: 23883826; PMCID: PMC4235393.
  8. Chou R, Fu R, Carrino JA, Deyo RA. Imaging strategies for low-back pain: systematic review and meta-analysis. Lancet. 2009;373(9662):463-472. doi:10.1016/S0140-6736(09)60172-0
All Posts