Postoperative changes in neurological function after 3-column osteotomy: risk factor analysis of 199 patients

OBJECTIVE The authors evaluated the neurological outcomes of adult spinal deformity patients after 3-column osteotomy (3CO), including severity and long-term improvement of neurological complications, as well as risk factors for neurological deficit at 1 year postoperatively. Although 3CO is effective for correcting rigid spinal deformity, it is associated with a high complication rate. Neurological deficits, in particular, cause disability and dissatisfaction. METHODS The authors retrospectively queried a prospective database of adult spinal deformity patients who underwent vertebral column resection or pedicle subtraction osteotomy between 2004 and 2014 by one surgeon at a tertiary care center. The authors included 199 adults with at least 1-year follow-up. The primary outcome measure was change in lower-extremity motor scores (LEMSs), which were obtained preoperatively, within 2 weeks postoperatively, and at 6 and 12 months postoperatively. To identify risk factors for persistent neurological deficit, the authors compared patient and surgical characteristics with a declined LEMS at 12-month follow-up (n =10) versus those with an improved/maintained LEMS at 12-month follow-up (n =189). RESULTS At the first postoperative assessment, the LEMS had improved in 15% and declined in 10% of patients compared with preoperative scores. At the 6-month follow-up, 6% of patients continued to have a decline in LEMS, and 16% had improvement. At 12 months, LEMS had improved in 17% and declined in 5% of patients compared with preoperative scores. The only factor significantly associated with a decline in 12-month LEMS was high-grade spondylolisthesis as an indication for surgery (OR 13, 95% CI 3.2-56). CONCLUSIONS Although the LEMS declined in 10% of patients immediately after 3CO 3 at 12 months postoperatively, only 5% of patients had neurological motor deficits. A surgical indication of high-grade spondylolisthesis was the only factor associated with neurological deficit at 12 months postoperatively.