Q 1.26. Spinal Cord Syndromes

Anatomy of the Spinal Cord:

• • The spinal cord is a cylindrical structure approximately 45 cm long and 1 cm wide.
  • It extends from the external margin of the foramen magnum (as a continuation of the medulla oblongata) down to the L2 vertebral level.
  • The spinal cord is entirely housed within the spinal meningeal layers.
  • Notably, there are two enlargements:
    • Cervical enlargement: Corresponds to the brachial plexus and spans from C4/5 to T1.
    • Lumbar enlargement: Associated with the lumbosacral plexus and lies between T11 and L1/2.
  • At L1, the spinal cord transitions into the conus medullaris (medullary cone).
  • The conus medullaris is short and at L2, it gives rise to the cauda equina (the horse’s tail), which consists of the remaining spinal nerves from L2 to Co1.

• Cervical Region:

• • Brachial Plexus Injury: Damage to the brachial plexus in the shoulder.
    • Features: Flaccid paralysis, sensory loss, Horner’s syndrome.
    • Cause: Trauma (e.g., shoulder dislocation, birth injury).

• Thoracic Region:

• • • • No specific spinal cord syndromes are commonly associated with this region.

• Lumbar Region:

• • Lumbosacral Radiculopathy: Irritation or compression of lumbar or sacral nerve roots.
    • Features: Radiating pain (sciatica), muscle weakness, reduced reflexes.
    • Cause: Disc herniation, spinal stenosis, degenerative changes.

• Sacral Region:
  • Cauda Equina Syndrome: Compression or injury of the cauda equina (nerve roots below the spinal cord termination).
    • Features: Bilateral leg weakness, saddle anesthesia, bladder/bowel dysfunction.
    • Cause: Disc herniation, trauma, tumors.
    • Gold standard: MRI (reveals spinal nerve compression and conus medullaris involvement).
    • Urgent management is essential, involving dexamethasone, followed by radiation or surgery.
    • Prognosis varies based on etiology and ambulatory status at presentation.

Anterior Cord Syndrome:

• • • Anterior spinal artery infarction affects the anterior two-thirds of the cord.
    • Motor paralysis on the same side below the lesion.
    • Loss of pain and temperature sensation on the opposite side.
    • Cause: Often related to flexion injuries, ischemia, or trauma.

Central Cord Syndrome:

• Motor weakness and sensory loss (often affecting upper limbs more than lower limbs).
• Cape-like distribution of sensory deficits.
• Cause: Commonly seen in elderly patients with cervical spondylosis or traumatic hyperextension injuries.