Mobilization of disk space
Interbody trials / spacers are inserted bilaterally in incremental fashion to loosen the annulus and anterior longitudinal ligament to achieve indirect foramina decompression by increasing the inter vertebral hight.
The focal lumbosacral kyphosis must be corrected during this maneuver.
The Listhesis can also be corrected to improve anterior vertebral apposition however care must be taken as anatomical reduction has been associated with L5 nerve root injury.
During this maneuver the L5 nerve roots EMG's must be monitored to avoid postoperative foot drop.