ABSTRACT
Iatrogenic flat back deformity is a well-known, long-term sequela of lumbar fusion, particularly multilevel lumbar fusions performed in the remote past, when there was less sensitivity to the preservation and restoration of sagittal balance. Indications for revision surgery include pseudoarthrosis, persistent back and neck pain attributable to loss of lordosis, and inability of compensatory knee flexion and hip extension to restore sagittal balance. The goal of revision surgery is to decompress the neural elements, restore sagittal balance and lumbar lordosis, and obtain adequate fusion along the construct. Patients receive an arterial line for intraoperative monitoring. Higher levels of care postoperatively are generally reserved for patients with high blood loss, long operative times, difficulty extubating at the conclusion of the case, or multiple medical comorbidities requiring close monitoring. Scar tissue from prior surgery can complicate dissection and increase the risk of injury to anterior and posterior structures, including the iliac veins, ureters, and dura.
