Can loss of disc height result in nerve compression?

Loss of Disc Height and Nerve Compression

Yes, loss of disc height can result in nerve compression, particularly in the cervical and lumbar spine, leading to radiculopathy symptoms including pain, weakness, and sensory deficits.

Mechanism of Nerve Compression Due to Disc Height Loss

• Loss of disc height is a key component of degenerative disc disease that can lead to nerve root compression through multiple mechanisms 1:

  • Reduced space between vertebrae causing foraminal narrowing
  • Bulging of the disc material into the neural foramen
  • Altered biomechanics leading to facet joint hypertrophy
  • Potential development of spondylolisthesis (vertebral slippage)

• When disc height decreases significantly (beyond 1.5 standard deviations below normal), major pathological changes occur that can compromise neural structures 2

Clinical Manifestations

• Cervical radiculopathy presents with a combination of arm pain, sensory dysfunction, and motor function loss, often with associated neck pain 3

• Nerve root compression due to loss of disc height can manifest as:

  • Radiating pain along the affected nerve distribution
  • Sensory deficits (numbness, tingling)
  • Motor weakness in specific muscle groups
  • Reduced reflexes 3, 4

Diagnostic Considerations

• MRI is the preferred imaging modality for evaluating nerve compression related to disc height loss due to its superior soft-tissue contrast and ability to visualize neural structures 5

• Loss of disc height on imaging is highly predictive of symptomatic tears extending into or beyond the outer annulus in patients with chronic pain 6

• Radiographs can identify spondylosis, degenerative disc disease, and spinal canal stenosis but have limited value in directly visualizing nerve compression 3

• CT provides good definition of bony elements and can assess neuroforaminal stenosis secondary to uncovertebral or facet hypertrophy, but is less sensitive than MRI for evaluating nerve root compression 3

Treatment Implications

• When cervical radiculopathy is present with active nerve root compression visible on diagnostic imaging, surgical decompression may be recommended if nonoperative measures have failed 3

• Anterior cervical discectomy with or without fusion (ACD/ACDF) is recommended for rapid relief (within 3-4 months) of arm/neck pain, weakness, and sensory loss compared to physical therapy or cervical collar immobilization 3

• For lumbar disc-related nerve compression, the main indication for surgical treatment should be pain rather than weakness alone 4

• Surgical options for addressing nerve compression due to loss of disc height include:

  • Decompression procedures to relieve pressure on neural elements
  • Fusion procedures to stabilize the segment and restore disc height
  • Newer techniques like uniportal endoscopic lumbar interbody fusion that aim to decompress nerve roots while restoring disc height and sagittal alignment 1

Clinical Pitfalls and Considerations

• Disc height loss alone may not always correlate with symptoms - imaging findings should be correlated with clinical presentation, as disc abnormalities are common in asymptomatic patients 5

• There appears to be a threshold effect where disc height loss beyond a certain point (approximately 1.5 standard deviations below normal) triggers major pathological changes that significantly increase the risk of nerve compression 2

• Disc bulges and protrusions may not represent discs with significantly different internal architecture based on discography findings, and both can contribute to nerve compression when associated with loss of disc height 6