Does the Position of Cage Affect the Clinical Outcome of Lateral Interbody Fusion in Lumbar Spinal Stenosis?

Study Design: A retrospective study. Objective: This study aims to identify the ideal cage position in lateral lumbar interbody fusion (LLIF) and to investigate if the posterior instrumentation would affect the indirect decompression. Methods: Patients underwent 2-stage surgeries: stage I was LLIF and stage II was percutaneous pedicle screws fixation after 1 week. Anterior disc height (ADH), posterior disc height (PDH), left and right foraminal height (FH), and segmental angle (SA) were measured on lateral computed tomography reconstructions. The cross-sectional area of the thecal sac (CSA) was determined by the outlined area of the thecal sac on a T2-weighted axial magnetic resonance imaging. The patients were subgroups according to the cage position: the anterior (cage located at the anterior 1/3 of disc space) and posterior groups (cage located at the posterior 2/3 of disc space). P values