spinal cord

general

· extends from brainstem to L1

· extends to L3 at birth

cross-section

· anterior fissure and posterior sulcus

Grey matter

· cell bodies

· H-shaped

· anterior and posterior horns

· central commissure

· anterior horn falls short of cord

White matter

· fibres

Dorsal columns

· ascending fibres

· transmit sensation

· pressure

· proprioception

· vibration

· lie between posterior horn and posterior sulcus

· divided into

· gracile tract (lower limb)

· cuneate tract (upper limb)

· fibres cross over in medulla

Lateral columns

· lie between posterior and anterior horns

· fibres cross over in cord

Lateral corticospinal tract

· descending fibres

· transmit voluntary motor

· lie posteriorly close to posterior horn

· arm is medial

· trunk is intermediate

· leg is lateral

Lateral spinothalamic tract

· ascending fibres

· transmit pain and temperature

· lie anteriorly close to anterior horn

· arm is medial

· trunk is intermediate

· leg is lateral

Anterior columns

· lie between anterior horns and anterior fissure

· fibres cross over in cord

Ventral corticospinal tract

· descending fibres

· transmit voluntary motor

· lie medially

Ventral spinothalamic tract

· ascending fibres

· transmit light touch

· lie anteriorly