Corpus3D

Trunk nerves (intercostal, sympathetic, vagus nerve)

Lateral fasciculus proprius

Fasciculus proprius lateralis

Origin
Thin sleeve of short fibres immediately around the grey matter, on the side of the cord between the anterior and posterior horn
Insertion
Runs up and down over a few segments and ends again in the grey matter of a neighbouring segment
Function
Largest of the three propriospinal tracts; it links the segments laterally and carries the fibres that tune trunk and limb muscles of successive levels to each other
Innervation
Intrinsic to the spinal cord
Movement & chain
Tunes the muscle activity of successive segments to each other
Palpation
Not palpable
Clinical
It lies right next to the lateral corticospinal and the spinothalamic tract, so a lateral cord lesion rarely hits this tract alone; in a hemisection (Brown-Sequard syndrome) it is lost together with those long tracts.
Segmental innervation
Along the whole length C1-Co1
In clinical practice
Relevant in rehabilitation after an incomplete cord injury, where recovery of intersegmental coordination is the basis of gait training
Region in the model
Trunk nerves (intercostal, sympathetic, vagus nerve)

Related structures