Spinal Cord Neuroanatomy: Structure and Function

Comprehensive vocabulary flashcards covering spinal cord anatomy, vertebral column levels, spinal tracts, dermatomes, and clinical lesion syndromes.

Foramen magnum

The cranial opening where the spinal cord exits the cranium as a continuation of the medulla oblongata.

$$L1-L2$$

The vertebral level where the spinal cord typically reaches before tapering to become the cauda equina.

Cauda equina

The bundle of spinal nerve roots extending below the end of the spinal cord ($L1-L2$).

Cervical enlargement

Expansion located at $C5-T1$ providing innervation for the upper extremities.

Lumbosacral enlargement

Expansion located at $L1-S3$ providing innervation for the lower extremities.

Epidural anesthesia at $T10$

Anesthesia level utilized for abdominal surgery or birth.

Epidural anesthesia at $L3-L5$

Anesthesia level utilized for limb surgery.

C8 spinal nerve

The specific spinal nerve that exits between the $C7$ and $T1$ vertebrae.

Anterior (ventral) horn

The portion of the spinal cord cross-section containing motor neurons for somatic innervation and voluntary motor control.

Lateral horn (Interomedial cell column)

The location of preganglionic autonomic cell bodies providing visceral innervation.

$T1-L2$ (Autonomic)

Spinal levels associated with the sympathetic nervous system for the whole body.

$S2-S4$ (Autonomic)

Spinal levels associated with the parasympathetic nervous system for the lower GI tract, bladder, and reproductive organs.

Posterior (dorsal) horn

The portion of the spinal cord cross-section containing sensory cell bodies and pseudounipolar neurons.

Fasciculus gracilis

Medially placed axons in the dorsal horn carrying sensory information from the lower extremities.

Fasciculus cuneatus

Laterally placed axons in the dorsal horn carrying sensory information from the upper extremities, beginning at level $T6$.

Spinothalamic tracts

Ascending pathways responsible for conveying pain and temperature sensation.

Spinocerebellar tracts

Ascending pathways responsible for conveying proprioception.

Lateral corticospinal tract

The primary descending motor pathway for skeletal muscle control.

Anterior column motor pathways

Includes the anterior corticospinal tract and the tectospinal, reticulospinal, and vestibulospinal tracts for posture reflexes.

Corticospinal tract (Upper Motor Neuron) lesion

Results in ipsilateral spastic paralysis and hyperreflexia below the level of the lesion.

Anterior horn cells (Lower Motor Neuron) lesion

Results in ipsilateral flaccid paralysis and decreased reflexes in a radicular distribution.

Dorsal column damage

Results in ipsilateral loss of proprioception, vibration sense, paresthesias, and the Romberg sign.

Spinal shock

A period from the first minutes to days (or a month) following a complete transection characterized by flaccid paralysis and complete absence of sensory and autonomic function.

Brown-Sequard Syndrome

A hemi-section of the spinal cord resulting in ipsilateral paralysis and vibration/proprioception loss with contralateral pain and temperature loss.

Dermatome $C6$

The sensory area clinically associated with the thumb.

Dermatome $T10$

The sensory area clinically associated with the umbilicus.

Dermatome $L5$

The sensory area clinically associated with the first toe.