Trusted medical expertise in seconds.

Access 1,000+ clinical and preclinical articles. Find answers fast with the high-powered search feature and clinical tools.

Try free for 5 days
Evidence-based content, created and peer-reviewed by physicians. Read the disclaimer.

Degenerative disk disease

Last updated: December 27, 2021

Summarytoggle arrow icon

Degenerative disk disease refers to a group of conditions in which disk material is displaced into the spinal canal. The condition can be asymptomatic or manifest as radiculopathy (due to compression of a spinal nerve root) or myelopathy (due to compression of the spinal cord). The site of nerve or cord compression can often be determined based on the patient's neurological deficits. Radiculopathy manifests with radicular pain, motor weakness, and loss of deep tendon reflexes in the dermatome and myotome territory of the compressed nerve root. Myelopathy is a medical emergency that typically manifests with motor weakness, sensory abnormalities (e.g., saddle anesthesia), and bowel and/or bladder disturbances. MRI findings consistent with physical exam findings confirm the diagnosis. Conservative management with analgesics and physiotherapy may be sufficient for isolated acute radiculopathy without severe paresis. Urgent surgical decompression is required for patients with spinal cord compression, conus medullaris syndrome, or cauda equina syndrome to prevent permanent neurological damage.

  • Age: most common at 30–50 years
  • Sex: > [1]
  • Approx. 80% of all Americans suffer from significant back pain at some point in their lives. [2]
  • Disk herniation is the cause of back pain in roughly 5% of cases.

Epidemiological data refers to the US, unless otherwise specified.

Intervertebral disks usually protrude/herniate posterolaterally, as the posterior longitudinal ligament is thinner than the anterior longitudinal ligament.

Degenerative disk disease may be asymptomatic and detected incidentally (e.g., on imaging performed for an unrelated condition). Examination findings vary depending on the location and severity of nerve root compression. [4][5]

As dermatomal territories often overlap (except in autonomous sensory zones) and muscles are often supplied by several myotomes, sensory and motor deficits may be absent or minimal if a single spinal root is compressed.

The affected nerve root is typically the one below the level of disk herniation (i.e., C4–C5 disk herniation leads to C5 radiculopathy; L4–L5 disk herniation leads to L5 radiculopathy).

Cervical radiculopathy [8]


Examination findings

May be normal or demonstrate specific motor or sensory deficits depending on the nerve root affected

Overview of cervical radiculopathies [9]
Radiculopathy Affected disk Sensory deficits Motor deficits Reduction of reflexes
C3/4 radiculopathy
  • C2–C4
  • Shoulder and neck area
  • None
C5 radiculopathy
  • C4–C5
C6 radiculopathy
  • C5–C6
  • From the upper lateral elbow over the radial forearm up to the thumb and radial side of index finger
C7 radiculopathy
  • C6–C7
  • Palmar: fingers II–IV (II ulnar half, III entirely, IV radial half)
  • Dorsal: medial forearm up to fingers II–IV
  • Triceps, wrist flexors, and finger extensors
C8 radiculopathy
  • C7–T1
  • Finger flexors
  • None

Provocative maneuvers

Lumbosacral radiculopathy [3]


Worsening of low back pain with lumbar flexion (e.g., on sitting) is suggestive of lumbar disk herniation, while improvement of pain with lumbar flexion is suggestive of lumbar spinal stenosis. [3]

Examination findings

May be normal or show specific motor or sensory deficits, depending on the affected nerve root

Overview of lumbosacral radiculopathies [9]
Radiculopathy Affected disk Sensory deficits Motor deficits Reduction of reflexes
L3 radiculopathy
  • L2–L3
  • Anterolateral area of the thigh
L4 radiculopathy
  • L3–L4
L5 radiculopathy
  • L4–L5
  • Lateral aspect of the thigh and knee, anterolateral aspect of the leg, dorsum of the foot, and the big toe
S1 radiculopathy
  • Dorsolateral aspect of thigh and leg, and the lateral aspect of the foot

S2 radiculopathy, S3 radiculopathy, S4 radiculopathy

  • None

Back pain associated with bowel or bladder dysfunction is concerning for spinal cord compression, cauda equina syndrome, and conus medullaris syndrome.

Provocative maneuvers

Leg raising maneuvers are used to screen for lumbosacral radiculopathy

The following table outlines common symptoms following compression of the spinal cord or cauda equina. Patients may also present with symptoms of incomplete spinal cord syndromes depending on the location of the herniated disk.

Overview of compressive myelopathy [12]
Spinal cord compression Conus medullaris syndrome Cauda equina syndrome
  • Damage to or compression of the cauda equina (nerve fibers L3–S5) located below L2
  • Common causes include large posteromedial disk herniation, trauma, and tumors.
  • Variable, bilateral
  • Sudden, bilateral
  • Gradual, typically unilateral
  • Localized neck or back pain
Motor symptoms
Sensory symptoms
  • Loss or reduction of all sensation below the affected level of the spinal cord
  • Symmetric bilateral perianal numbness
  • Sensory dissociation
  • Saddle anesthesia: lack of sensitivity in the dermatomes S3–S5, affecting the areas around the anus, genitalia, and inner thighs (may be asymmetric)
  • Asymmetric unilateral numbness and/or paresthesia in lower limb dermatomes
Urogenital and rectal symptoms
  • Sphincter dysfunction with urinary or bowel urgency, retention, or incontinence

Spinal cord compression, conus medullaris syndrome, and cauda equina syndrome are medical emergencies that have the potential to cause permanent neurological damage. [15]

Cauda equina syndrome typically manifests with lower motor neuron signs. Spinal cord compression and conus medullaris manifest with a combination of lower motor neuron signs (at the level of compression) and upper motor neuron signs (below the level of compression).

Degenerative disk disease is diagnosed on the basis of characteristic clinical features in conjunction with abnormal imaging.

General principles [16][17][18]

A diagnosis of degenerative disk disease should not be made based on imaging alone; up to 30% of asymptomatic individuals have abnormal disk appearances on MRI. [22]

MRI spine without IV contrast [8][16][22]

CT myelogram [16][18][23]

X-ray spine [18][23]

See “Acute back pain” for details on the distinguishing characteristics and management of the underlying etiology.

The differential diagnoses listed here are not exhaustive.


Management of symptomatic degenerative disk diseases is detailed here. Treatment of acute spinal cord compression varies based on the underlying etiology and may include decompressive surgery (e.g., for disk herniation) or IV steroids and radiation therapy (for malignant compression). See “Urgent spinal causes of acute back pain” for further information.

Conservative management [8][20][21]

About 90% of lumbar disk herniations with acute sciatica start to improve within 6 weeks and resolve by 12 weeks with conservative management. [24]

Surgery [8][21]

  1. Manfrè L, Van Goethem J. The Disc and Degenerative Disc Disease. Springer Nature ; 2020
  2. Jameson JL, Fauci AS, Kasper DL, Hauser SL, Longo DL, Loscalzo J. Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2). McGraw-Hill Education / Medical ; 2018
  3. Campbell WW. DeJong's The Neurologic Examination. Lippincott Williams & Wilkins ; 2012
  4. Anekstein Y, Blecher R, Smorgick Y, Mirovsky Y. What is the Best Way to Apply the Spurling Test for Cervical Radiculopathy?. Clin Orthop Relat Res. 2012; 470 (9): p.2566-2572. doi: 10.1007/s11999-012-2492-3 . | Open in Read by QxMD
  5. Amin RM, Andrade NS, Neuman BJ. Lumbar Disc Herniation. Curr Rev Musculoskelet Med. 2017; 10 (4): p.507-516. doi: 10.1007/s12178-017-9441-4 . | Open in Read by QxMD
  6. Ropper AE, Ropper AH. Acute Spinal Cord Compression. N Engl J Med. 2017; 376 (14): p.1358-1369. doi: 10.1056/nejmra1516539 . | Open in Read by QxMD
  7. Bhandutia AK, Winek NC, Tomycz ND, Altman DT. Traumatic Conus Medullaris Syndrome. JBJS Case Connector. 2016; 6 (2): p.e38. doi: 10.2106/ . | Open in Read by QxMD
  8. Brouwers E, van de Meent H, Curt A, Starremans B, Hosman A, Bartels R. Definitions of traumatic conus medullaris and cauda equina syndrome: a systematic literature review. Spinal Cord. 2017; 55 (10): p.886-890. doi: 10.1038/sc.2017.54 . | Open in Read by QxMD
  9. Edlow JA. Managing Nontraumatic Acute Back Pain. Ann Emerg Med. 2015; 66 (2): p.148-153. doi: 10.1016/j.annemergmed.2014.11.011 . | Open in Read by QxMD
  10. Wang Y-XJ, Griffith JF, Zeng X-J, et al. Prevalence and Sex Difference of Lumbar Disc Space Narrowing in Elderly Chinese Men and Women: Osteoporotic Fractures in Men (Hong Kong) and Osteoporotic Fractures in Women (Hong Kong) Studies. Arthritis & Rheumatism. 2013; 65 (4): p.1004-1010. doi: 10.1002/art.37857 . | Open in Read by QxMD
  11. Freburger JK, Holmes GM, Agans RP, et al. The rising prevalence of chronic low back pain. Arch Intern Med. 2009; 169 (3): p.251-8. doi: 10.1001/archinternmed.2008.543 . | Open in Read by QxMD
  12. Brinjikji W, Diehn FE, Jarvik JG, et al. MRI Findings of Disc Degeneration are More Prevalent in Adults with Low Back Pain than in Asymptomatic Controls: A Systematic Review and Meta-Analysis. American Journal of Neuroradiology. 2015; 36 (12): p.2394-2399. doi: 10.3174/ajnr.a4498 . | Open in Read by QxMD
  13. BRAZIS, Masdeu JC, PhD M, Biller J. Localization in Clinical Neurology 8. LWW ; 2021
  14. McCartney S, Baskerville R, Blagg S, McCartney D. Cervical radiculopathy and cervical myelopathy: diagnosis and management in primary care. Br J Gen Pract. 2018; 68 (666): p.44-46. doi: 10.3399/bjgp17X694361 . | Open in Read by QxMD
  15. Iyer S, Kim HJ. Cervical radiculopathy. Current reviews in musculoskeletal medicine. 2016; 9 (3): p.272-80. doi: 10.1007/s12178-016-9349-4 . | Open in Read by QxMD
  16. Expert Panel on Neurological Imaging: Agarwal V, Shah LM, et al. ACR Appropriateness Criteria® Myelopathy: 2021 Update. J Am Coll Radiol. 2021; 18 (5S): p.S73-S82. doi: 10.1016/j.jacr.2021.01.020 . | Open in Read by QxMD
  17. ACR Appropriateness Criteria Low Back Pain. Updated: March 1, 2021. Accessed: June 14, 2021.
  18. Expert Panel on Neurological Imaging: McDonald MA, Kirsch CFE, et al. ACR Appropriateness Criteria: Cervical Neck Pain or Cervical Radiculopathy. J Am Coll Radiol. 2019; 16 (5S): p.S57-S76. doi: 10.1016/j.jacr.2019.02.023 . | Open in Read by QxMD
  19. Spina bifida. Updated: August 27, 2014. Accessed: February 17, 2017.
  20. Childress MA, Becker BA. Nonoperative Management of Cervical Radiculopathy. Am Fam Physician. 2016; 93 (9): p.746-54.
  21. Berry JA, Elia C, Saini HS, Miulli DE. A Review of Lumbar Radiculopathy, Diagnosis, and Treatment. Cureus. 2019; 11 (10): p.e5934. doi: 10.7759/cureus.5934 . | Open in Read by QxMD
  22. Hasz MW. Diagnostic Testing for Degenerative Disc Disease. Adv Orthop. 2012; 2012 : p.1-7. doi: 10.1155/2012/413913 . | Open in Read by QxMD
  23. Patel ND, Broderick DF, Burns J, et al. ACR Appropriateness Criteria Low Back Pain. J Am Coll Radiol. 2016; 13 (9): p.1069-1078. doi: 10.1016/j.jacr.2016.06.008 . | Open in Read by QxMD
  24. Saal JA, Saal JS. Nonoperative treatment of herniated lumbar intervertebral disc with radiculopathy. An outcome study.. Spine. 1989; 14 (4): p.431-7. doi: 10.1097/00007632-198904000-00018 . | Open in Read by QxMD
  25. Christelis N, Simpson B, Russo M, et al. Persistent Spinal Pain Syndrome: A Proposal for Failed Back Surgery Syndrome and ICD-11. Pain Medicine. 2021; 22 (4): p.807-818. doi: 10.1093/pm/pnab015 . | Open in Read by QxMD