Several factors may predict neurologic complications after adult spinal deformity surgery
Results presented at the North American Spine Society Annual Meeting showed several patient and surgical factors may predict neurologic complications after adult spinal deformity surgery.
Tina Raman, MD, and colleagues identified 949 adult patients who underwent multilevel complex spine fusion for adult spinal deformity. Patients were included if they had a diagnosis of either adult degenerative or idiopathic scoliosis with a curvature of the spine measuring 20° or more, a sagittal vertical axis greater than 5 cm and more than five levels fused.
Patient characteristics, surgical details
Ramen noted patients who sustained a neurologic complication were significantly older, had a higher BMI, more commonly had a history of previous spine surgery and had a higher modified frailty index.
“We also found that patients more commonly had a diagnosis of [chronic obstructive pulmonary disease] COPD and osteoporosis,” Raman said in her presentation here.
Raman noted patients who sustained a neurologic complication had significantly worse preoperative deformity. Although patients who sustained a neurologic complication continued to have worse deformity postoperatively compared with patients who did not sustain a neurologic complication, Raman noted both groups of patients had significant improvements in postoperative deformity parameters.
Patients who developed a neurologic complication had higher invasiveness index, defined by the Mirza Invasiveness Index, and higher estimated blood loss, according to Raman.
“They more commonly underwent a three-column osteotomy as part of their procedure – posterior column osteotomy, interbody fusion, multi-rod configuration – and more commonly had a use of the connectors as part of their construct,” Raman said.
Neurologic complications
Raman noted 18% of patients had radiculopathy, including 15.8% of patients with a sensory deficit and 2.2% of patients with a motor deficit. Patients had a rate of spinal cord injury of 0.7% and a rate of cauda equina of 0.1%.
“Looking at the rate of unplanned reoperation, 30 patients required an unplanned reoperation, 2.2% of these patients required unplanned reoperation for radiculopathy,” Raman said. “This was found to be due to residual stenosis in about 1.3% of cases.”
Intraoperatively, 0.4% of patients had a malpositioned interbody device or pedicle screw and researchers believed the neurologic injury was related to presumed traction retraction injury in 0.5% of patients, according to Raman.
“At 3-year follow-up, 29.6% of the patients who had a neurologic complication had complete resolution of symptoms, as well as their motor deficit,” Raman said. “Mean strength grading at final follow-up was about 4.14.”
She added 24.6% of patients who had a neurologic deficit had a partial resolution of their injury and 45.8% of patients had no resolution of the injury.
“By logistic regression analysis, we found that a history of previous spine surgery, higher BMI, undergoing a three-column osteotomy, greater age and higher preoperative pelvic tilt were independent predictors of sustaining a neurologic complication,” Raman said.
Collapse
Dinizo M, et al. Paper 234. Presented at: North American Spine Society Annual Meeting. Sept. 29 - Oct. 2, 2021; Boston (hybrid meeting).
Read more about