Can a T11/T12 disc prolapse on the left side, with compression of the spinal cord, cause left leg pain, weakness, atrophy, and coordination problems?

T11/T12 Disc Prolapse and Left Leg Symptoms

Yes, a T11/T12 disc prolapse on the left side with compression of the spinal cord can cause left leg pain, weakness, atrophy, and coordination problems. This presentation is consistent with thoracic disc herniation causing myelopathy and/or radiculopathy affecting the left lower extremity.

Pathophysiology and Clinical Presentation

• Thoracic disc herniations with spinal cord compression can cause a variety of neurological symptoms including pain (local or radicular), weakness, sensory disturbances, and sphincter dysfunction 1.

• The T11/T12 level is at the thoracolumbar junction, where disc herniations commonly present with a mixed picture of upper and lower motor neuron signs due to the proximity to the conus medullaris 2.

• Compression at this level can affect:

  • Nerve roots exiting below the level of compression
  • The spinal cord itself (myelopathy)
  • The cauda equina in some cases 2

• Specifically for T11/T12 disc herniations:

  • Lower extremity weakness is common (75% of patients)
  • Accentuated patellar tendon reflexes may be present
  • Sensory disturbance can affect the anterolateral thigh or entire leg
  • Bowel and bladder dysfunction may occur in severe cases 2

Mechanism of Symptoms

• The left-sided disc prolapse explains the left-sided symptoms due to compression of:

  • Ipsilateral descending motor tracts in the spinal cord
  • Ipsilateral nerve roots at or below the level of compression 1, 2

• Muscle atrophy occurs due to lower motor neuron damage when nerve roots are compressed, or can develop over time with disuse from weakness 1.

• Coordination problems result from disruption of proprioceptive pathways in the posterior columns of the spinal cord, which is common in thoracic disc herniations 3.

Diagnostic Considerations

• Thoracic disc herniations can sometimes mimic lumbar disc disease, making diagnosis challenging 4.

• MRI is the preferred imaging modality for evaluating spinal cord compression and should be performed promptly when symptoms suggest myelopathy 1.

• The clinical presentation of thoracic disc herniation can vary widely, and symptoms may evolve over time from mild to severe 5.

Clinical Course and Prognosis

• If left untreated, spinal cord compression can lead to progressive neurological deterioration including worsening weakness, sensory loss, and sphincter dysfunction 1.

• The natural history of untreated spinal cord compression is often one of relentless progression 1.

• Patients with paralysis (either at presentation or after treatment) have a much shorter life expectancy than ambulatory patients 1.

• Recovery of neurologic function after treatment is largely dependent on pretreatment status - only about 30% of non-ambulatory patients regain the ability to walk 1.

Treatment Considerations

• Prompt surgical decompression is often necessary for thoracic disc herniations causing significant neurological deficits 5.

• High-dose corticosteroids (dexamethasone) may be administered prior to definitive treatment if there is significant clinical suspicion of spinal cord compression 1.

• Remarkable recovery is possible even with profound neurological deficits if adequate decompression is achieved, though earlier intervention generally leads to better outcomes 5.

Important Caveats

• The symptoms of thoracic disc herniation can be misleading, and diagnosis may be delayed until other causes have been excluded 5.

• Back pain often precedes profound myelopathy and may serve as an early warning sign 5.

• Thoracic disc herniations causing acute myelopathy are often large or giant, and may be calcified, causing significant cord compression 5.