Posterior fasciculus proprius

The proper fasciculi, or spinospinal fasciculi, or propriospinal tracts,[1] are groups of short fibres, ascending and descending, and crossed and uncrossed, within the spinal cord.

These fibres are grouped into anterior, posterior, and lateral regions and make up a spinal pathway. Descending dorsal root collaterals are often included in the pathway.

There is an anterior fasciculus proprius, a lateral fasciculus proprius and the posterior fasciculus proprius.

The posterior fasciculus proprius arises from cells in the posterior column; their axons bifurcate (fork) into ascending and descending branches which occupy the ventral part of the funiculus close to the grey column.

They are intersegmental and run for varying distances sending off collaterals and terminals to the grey matter.