prespondylolisthesis

A condition predisposing to spondylolisthesis, consisting of a defect in the laminae of a lumbar vertebra but before development of any displacement of the vertebral body. See spondylolysis.

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pre·spon·dy·lo·lis·the·sis (pre-spon″də-lo-lis-theґsis) a congenital defect in the last lumbar vertebra consisting of a bilateral defect in the neural arches at the pedicles.