The Science Behind Herniated Bulging Discs and MRI

How are MRIs used to help diagnose bulging and herniated discs and help healthcare providers develop effective treatment programs for individuals experiencing back pain symptoms?

Herniated Bulging Disc MRI

A herniated bulging disc is often identified during magnetic resonance imaging (MRI); however, it’s usually an incidental finding that was done for other reasons where spinal problems and/or injuries are found. A bulging disc is relatively common, even in individuals who experience no symptoms. A herniated or bulging disc in the back can be identified with an MRI test, typically recommended when someone experiences back pain symptoms for at least six weeks. (American Academy of Neurological Surgeons, 2024) Normal wear and tear and age cause changes in the spinal disc/s cushion to bulge and become misaligned with the spine. (Brinjikji W. et al., 2015) And with a herniated disc, it can press against the spinal cord and nerves. Repeated heavy lifting, practicing unhealthy postures, a history of back injuries, or underlying health conditions are common causes.

Bulging Disc

Bulging discs are common even in healthy individuals but can be difficult to interpret independently on an MRI, so other symptoms and findings are as important in diagnosis.

Causes

A bulging disc is usually considered age-related degenerative changes that cause the disc to bulge downward with gravity. (Penn Medicine, 2018)

Symptoms

Many with a bulging disc won’t have symptoms initially. (Wu P. H., Kim H. S., & Jang I. T. 2020) MRI findings are helpful but need to be evaluated alongside other symptoms (American Academy of Neurological Surgeons, 2024) (Penn Medicine, 2018)

• Back pain
• Pain in the legs and/or buttocks
• Changes in gait and/or difficulty walking
• Symptoms that affect just one side

A significant bulge is expected to cause leg pain due to irritation to the nerves going down the legs. (Amin R. M., Andrade N. S., & Neuman B. J. 2017) As the condition progresses, more than one disc can be affected, leading to other spinal conditions, including spinal stenosis.

A Bulging Disc On MRI

A disc bulge will measure over 25% of the total disc circumference. Its displacement is usually 3 millimeters or less from the normal shape and position of the disc. (Radiopaedia, 2024)

Herniated Disc

A herniated disc shifts out of its correct position and compresses nearby spinal nerves, causing pain and mobility issues.

Causes

Herniated disc causes include: (American Academy of Orthopaedic Surgeons, 2022)

• Automobile accident injuries
• Work or sports repetitive motion injuries
• Heavy lifting and/or Incorrect lifting practices
• Being overweight
• Sedentary jobs and/or lifestyles that place pressure on the spine when sitting.
• Smoking can speed up degenerative damage to the spine.

Symptoms

Symptoms include back and leg pain as well as: (American Academy of Orthopaedic Surgeons, 2022)

• Tingling sensations
• Numbness
• Burning sensations
• Muscle spasms
• Muscle weakness

Herniated Disc on MRI

Herniated discs will measure less than 25% of the total disc circumference. However, herniation is based on the type and can include: (Wei B., & Wu H. 2023)

• Disc Protrusion – the displacement is limited, and the ligaments are intact.
• Disc Extrusion – part of the disc remains connected but has slipped through the annulus or outer covering of the disc.
• Disc Sequestration – a free fragment has separated and broken off from the main disc.

Candidates For Spinal MRI

The MRI is generally safe for most, including those with implanted cardiac devices like newer-model pacemakers. (Bhuva A. N. et al., 2020) However, it’s important to ensure that the healthcare team is aware of cochlear implants or other devices so that necessary precautions can be taken. It is recommended for all individuals that symptoms be present for six weeks before an MRI. A specialist may want to see MRI results sooner, especially if symptoms include: (American Academy of Neurological Surgeons, 2024)

• A specific injury, like a fall that caused the pain
• Recent or current infection or fever with spinal symptoms
• Significant weakness in arms or legs
• Loss of pelvic sensation.
• A history of metastatic cancer.
• Loss of bladder or bowel control

An MRI may be needed if symptoms are rapidly worsening. However, many with a disc bulge don’t have symptoms at all. In most cases, an MRI is an outpatient procedure that can be completed in an hour or less but can take longer if contrast dye is used. The healthcare provider will provide specific instructions about MRI preparation.

Treatment

Treatment for a herniated or bulging disc depends on the cause and severity of symptoms.

Bulging Disc

Many disc bulges don’t require treatment; however, bulging disc pain treatment can include: (American Academy of Orthopaedic Surgeons, 2022) (American Academy of Neurological Surgeons, 2024)

• Rest
• No heavy lifting
• Limited walking
• Over-the-counter pain relief, including nonsteroidal anti-inflammatory drugs (NSAIDs).
• Physical therapy
• In rare cases that have not resolved with conservative treatment, surgery may be recommended.

Remember that the MRI findings may not identify or rule out all conditions, including muscle strains or ligament injuries, which may require different treatments, such as targeted stretches and exercises. (Brinjikji W. et al., 2015) (Fujii K. et al., 2019)

Herniated Disc

Treatment depends on the cause and severity of symptoms, if any. It can include stand-alone or a combination of physical therapy, medication, and steroid injections. Cases usually resolve in six to 12 weeks (Penn Medicine, 2018). Electrical nerve stimulation may be performed through specialized devices and/or acupuncture to help with nerve compression. (National Institute of Neurological Disorders and Stroke, 2020) Surgery may be recommended if conservative treatments fail to achieve significant pain relief and healing. (Wang S. et al., 2023)

Injury Medical Chiropractic and Functional Medicine Clinic

A healthcare provider can discuss treatment options such as pain medication, physical therapy, and surgery. Injury Medical Chiropractic and Functional Medicine Clinic works with primary healthcare providers and specialists to develop an optimal health and wellness solution. We focus on what works for you to relieve pain, restore function, and prevent injury. Regarding musculoskeletal pain, specialists like chiropractors, acupuncturists, and massage therapists can help mitigate the pain through spinal adjustments that help the body realign itself. They can also work with other medical professionals to integrate a treatment plan to resolve musculoskeletal issues.

Root Causes of Spinal Stenosis

References

American Academy of Neurological Surgeons. (2024). Herniated disc. www.aans.org/patients/conditions-treatments/herniated-disc/

Brinjikji, W., Diehn, F. E., Jarvik, J. G., Carr, C. M., Kallmes, D. F., Murad, M. H., & Luetmer, P. H. (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. American journal of neuroradiology, 36(12), 2394–2399. doi.org/10.3174/ajnr.A4498

Penn Medicine. (2018). Bulging Disc vs. Herniated Disc: What’s The Difference? Penn Musculoskeletal and Rheumatology Blog. www.pennmedicine.org/updates/blogs/musculoskeletal-and-rheumatology/2018/november/bulging-disc-vs-herniated-disc

Wu, P. H., Kim, H. S., & Jang, I. T. (2020). Intervertebral Disc Diseases PART 2: A Review of the Current Diagnostic and Treatment Strategies for Intervertebral Disc Disease. International journal of molecular sciences, 21(6), 2135. doi.org/10.3390/ijms21062135

Amin, R. M., Andrade, N. S., & Neuman, B. J. (2017). Lumbar Disc Herniation. Current reviews in musculoskeletal medicine, 10(4), 507–516. doi.org/10.1007/s12178-017-9441-4

Radiopaedia. (2024). Disc herniation. radiopaedia.org/articles/disc-herniation

American Academy of Orthopaedic Surgeons. (2022). Herniated disk in the lower back. orthoinfo.aaos.org/en/diseases–conditions/herniated-disk-in-the-lower-back/

Wei, B., & Wu, H. (2023). Study of the Distribution of Lumbar Modic Changes in Patients with Low Back Pain and Correlation with Lumbar Degeneration Diseases. Journal of pain research, 16, 3725–3733. doi.org/10.2147/JPR.S430792

Bhuva, A. N., Moralee, R., Moon, J. C., & Manisty, C. H. (2020). Making MRI available for patients with cardiac implantable electronic devices: growing need and barriers to change. European radiology, 30(3), 1378–1384. doi.org/10.1007/s00330-019-06449-5

Brinjikji, W., Luetmer, P. H., Comstock, B., Bresnahan, B. W., Chen, L. E., Deyo, R. A., Halabi, S., Turner, J. A., Avins, A. L., James, K., Wald, J. T., Kallmes, D. F., & Jarvik, J. G. (2015). Systematic literature review of imaging features of spinal degeneration in asymptomatic populations. AJNR. American journal of neuroradiology, 36(4), 811–816. doi.org/10.3174/ajnr.A4173

Fujii, K., Yamazaki, M., Kang, J. D., Risbud, M. V., Cho, S. K., Qureshi, S. A., Hecht, A. C., & Iatridis, J. C. (2019). Discogenic Back Pain: Literature Review of Definition, Diagnosis, and Treatment. JBMR plus, 3(5), e10180. doi.org/10.1002/jbm4.10180

Wang, S., Zhao, T., Han, D., Zhou, X., Wang, Y., Zhao, F., Shi, J., & Shi, G. (2023). Classification of cervical disc herniation myelopathy or radiculopathy: a magnetic resonance imaging-based analysis. Quantitative imaging in medicine and surgery, 13(8), 4984–4994. doi.org/10.21037/qims-22-1387

National Institute of Neurological Disorders and Stroke. (2020). Low back pain fact sheet. Retrieved from www.ninds.nih.gov/sites/default/files/migrate-documents/low_back_pain_20-ns-5161_march_2020_508c.pdf