A retrolisthesis is a posterior displacement of one vertebral body with respect to the subjacent vertebra to a degree less than a luxation (dislocation).

[citation needed] Pain may be experienced as a result of irritation to the sensory nerve roots by bone depending on the degree of displacement and the presence of any rotatory positioning of the individual spinal motion segments.

(3)[citation needed] Since the vertebral body in a retrolisthesis moves in a posterior direction, the grading used for spondylolistheses is of little use.

It is however useful to divide the anterior to posterior dimension of the intervertebral foramina (IVF) (4) into four equal units.

They may also involve muscles through spasm as a result of nerve malfunction due to pressure caused by the posterior displacement of the vertebra encroaching on the contents of the IVF.

The greater the posterior displacement, the more significant it is for producing a dysfunctional spinal cord or even a cauda equina syndrome.

[citation needed] Joint stability is easily evaluated by the use of flexion and extension lateral x-ray views of the spine.

If either translation or angular change is determined from flexion to extension to the degree shown in the table below, then Category IV instability is present.