Delayed postoperative neurological complication in a patient with congenital kyphoscoliosis: recovered by revision of the 4-rod instrumentation technique: case report.

The authors report a case of progressive congenital kyphoscoliosis in which the patient, a boy, originally underwent combined anterior and instrumented posterior spinal fusion at the age of 7 years and 3 months. Early proximal junctional kyphosis and implant failure mandated proximal extension of implants with 2 new rods connected to the old caudad short rods. At the 3-year follow-up, clinical and CT assessment revealed a thoracolumbar pseudarthrosis for which the patient underwent a 2-stage procedure without complication. Recordings of somatosensory evoked potentials intraoperatively were normal. Twelve hours after surgery, his neurological status started to progressively deteriorate. The patient was brought to the operating room, and the initially achieved correction was reversed by an apex-only exposure of the 4-rod system. After surgery the patient started to show progressive improvement in his neurological function. A final myelography was performed and showed free passage of the dye without evidence of obstruction. Clinically, the patient continued to improve and at his 3-month follow-up had near-complete resolution of his neurological deficits. Findings on his physical examination were normal at the final 12-year follow-up. Despite normal findings on intraoperative neuromonitoring, a delayed neurological deficit can occur after complex spine reconstruction. Preoperative risk assessment, surgical approach, and instrumentation deserve careful attention. Advantages of a 4-rod construct are discussed in this case.