Perioperative neurologic complications during spinal fusion surgery: incidence and trends.

BACKGROUND CONTEXT: Perioperative neurologic complications after spine surgery may increase morbidity and health-care costs related to the procedure.

PURPOSE: We estimate the national incidence of perioperative neurologic complications following anterior cervical discectomy and fusion (ACDF), posterior cervical fusion, and thoracolumbar fusion procedures using the Nationwide Inpatient Sample (NIS) data from 1999 to 2011. Additionally, we identify risk factors for developing perioperative neurologic complications and the effects of these injuries on quantifiable patient outcomes.

STUDY DESIGN: A cross-sectional study was carried out.

PATIENT SAMPLE: All patients included in the NIS databases from 1999 to 2011 comprised the sample.

OUTCOME MEASURES: The primary outcome evaluated was the incidence of new neurologic deficits following elective spine surgery. Secondary outcomes evaluated include length of hospital stay, total hospital charges, hospital mortality rate, and discharge disposition.

METHODS: A retrospective analysis of the NIS databases from the years 1999 to 2011 was conducted to identify the proportion of patients who underwent ACDFs, posterior cervical fusions, and thoracolumbar fusions who also developed perioperative neurologic complications. Statistical analyses were also conducted to identify statistically significant differences in demographics and outcomes between patients who did and did not develop perioperative neurologic complications.

RESULTS: From 1999 to 2011, the total national incidence of perioperative neurologic deficits following elective ACDFs, posterior cervical fusions, and thoracolumbar fusions was 0.82%, which equates to a total of 15,066 patients who experienced these complications. The annual incidence rate of perioperative neurologic deficits has increased 54.41%, from 0.68% in the year 1999 to 1.05% in the year 2011. Additionally, the total number of procedures performed increased from 82,167 in 1999 to 186,353 in the year 2011. Perioperative neurologic deficits were associated with longer lengths of stay (9.68 days vs. 2.59 days; p<.001), higher total charges ($110,326.23 vs. $48,695.93; p<.001), and higher in-hospital mortality (2.84% vs. 0.13%; p<.001).

CONCLUSIONS: The incidence rate of perioperative neurologic deficits associated with elective spine surgery documented in the NIS has increased over the time period from 1999 to 2011. The number of elective spine procedures performed has also increased over the same time period. Finally, outcomes data indicate that occurrence of perioperative neurologic complications is associated with increased rates of morbidity and mortality, as well as increased health-care use and cost. These trends indicate that the perioperative neurologic complications following spine surgery represent a growing problem in today's health-care system; further study is warranted to prevent and treat these complications to improve patient care and reduce health-care use and cost.