Imaging of isthmic spondylolisthesis in a 49-year-old woman. (A) Lateral radiography reveals L4-5 isthmic spondylolisthesis. (B) T2-weighted sagittal magnetic resonance imaging (MRI) reveals L4-5 spondylolisthesis without degeneration at the L5-S1 level. (C) Sagittal MRI reveals reduced slippage at the L4-5 level and no acceleration of degeneration at the L5-S1 level after minimally invasive transforaminal lumbar interbody fusion at L4-5 (5 years after surgery). (D) Seven years later, lateral radiography reveals complete interbody fusion of L4-5 and good maintenance of disc height at the L5-S1 segment.