Retrolisthesis:

Retrolisthesis is the relative posterior displacement of vertebra on the one below it. Retrolisthesis is the result of degenerative disc changes. Indications for surgery are based on severity and duration of symptoms and a neurologic deficit rather than on degree of slip. Also, if there is an obvious increase in deformity, surgery is indicated.

The pinch occurs due to buckling of the post longitudingal ligament and narrowing of the spinal canal as a result of displacement of the two vertebra. Treatment initially is activity modification and meds for pain control. If the pain is unrelenting despite best efforts or if a progressive neurologic deficit develops, then surgery may be indicated.