Spondylolisthesis

In simple terms, spondylolisthesis describes the displacement of a vertebrae or the vertebral column in relation to the vertebrae below. It was first described in 1782 by a Belgian obstetrician, Dr. Herbinaux.citation needed] He reported a bony prominence anterior to the sacrum that obstructed the vagina of a small number of patients. The term “spondylolisthesis” was coined in 1854, from the Greek “spondylo” for vertebrae and “olisthesis” for slip.citation needed] These "slips" occur most commonly in the lumbar spine.

A hangman's fracture is a specific type of spondylolisthesis where the C1 vertebra is displaced anteriorly relative to the C2 vertebra due to fractures of the C2 vertebra's pedicles.