CORTICOSPINAL TRACT-LATERAL CS TRACT SUPPLY

SUMMARY

1. The tract lies in the lateral white column, behind the attachment of the denticulate ligaments.

2. The arm fibers cross at a higher level than the leg fibers and the tract becomes smaller as it passes down since the fibers are leaving it at all levels.

3. 98% of fibers synapse on interneurons (lamina VII & VIII) which project to alpha & gamma motor neurons of lamina IX of the anterior horn.

4. 2% of fibers synapse directly onto the motor neurons. These originate from layer V (ganglionic layer) of the cortex, giant Betz cells.

5. Cervical fibers are located more medially than fibers serving the lower extremities: explains central cord syndrome.

Reference(s)

R.M.H McMinn (1998). Last’s anatomy: regional and applied. Edinburgh: Churchill Livingstone. Get it on Amazon.
Drake, Richard L., et al. Gray's Anatomy for Students. Elsevier, 2023. Get it on Amazon.