Revision 12 for 'Lateral corticospinal tract'All Revisions
Lateral corticospinal tract
The lateral corticospinal tract is formed at the level of the of the medullary pyramids when the majority (90%) of descending corticospinal tract fibers decussate – the majority of the remaining non-decussating 10% of fibers form the much smaller anterior corticospinal tract, with only a few non-decussated fibers entering the lateral corticospinal tract 1,2.
The lateral corticospinal tract descends along the lateral funicular and then lies anterolateral to the dorsal horn. As it descends it deviates to the dorsolateral surface of the spinal cord, with fibers synapsing with grey matter motor neurons. As it does so it commensurately diminishes in size. At approximately the fourth sacral level, it terminates entirely.
The lateral corticospinal tract mostly mediates fine-motor movement of the upper and lower limbs 3.