The cauda equina contains 10 pairs of nerve roots (aka radicles, from Latin radix or root) that travel inferiorly from the spinal cord (spinalis) to the filum terminale (Latin meaning “terminal thread”). Cauda equina syndrome is a clinical syndrome of polyradiculopathy where the nerve roots are often pinched by herniated discs. Cauda equina derives its name from Latin due to its resemblance to a “horse tail” (at the opposite end of a horse from its head).