Lippincott Williams & Wilkins

Presence and progression of L5-S1 spondylolisthesis by >2 mm OR. Progressive loss of L5-S1 disc height by >2 mm based on radiographs. Symptomatic segmental degeneration defined by: Revision Cho (2009) Retrospective cohort study Presence of ASD based on modified Weiner classification161 on radiographic evaluation‡‡: ................
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