General Session: Adult Spinal Deformity-2

Presented by: A. Samuel - View Audio/Video Presentation (Members Only)

Author(s):

A. Samuel(1), M. Fu(2), N. Anandasivam(1), A. Lukasiewicz(1), M. Webb(1), H.J. Kim(2), J. Grauer(1)

(1) Yale University School of Medicine, New Haven, CT, United States
(2) Hospital for Special Surgery, New York City, NY, United States

Abstract

Introduction: Morbidity is high after long posterior fusions for adult spinal deformity. While previous reports have demonstrated an association with perioperative outcomes and the extent of spinal fusion, no study has analyzed the independent effect of extent of spinal fusion and surgical invasiveness (number of levels, surgical approach, pelvic fixation) after controlling for operative time. With modern surgical techniques that minimize the risk of acute intraoperative errors, operative time (and the associated effects of longer anesthesia time and bleeding) may be the leading driver of postoperative complications.

Methods: All patients, age 40 or older, undergoing long posterior spinal fusion (7 levels or more) for spinal deformity were identified in the 2010 - 2013 National Surgical Quality Improvement Program (NSQIP) database. The rates of short-term complications were determined. Multivariate analysis was then used to determine the independent effect of operative timing, surgical invasiveness (number of levels fused, combined anterior-posterior fusions, pelvic fixation, osteotomies, perioperative transfusion) , and other patient factors on perioperative outcomes.

Results: A total of 1,066 patients undergoing posterior spinal fusion for adult spinal deformity were identified. The overall rate of complications was 16.23%, while the rate of serious complications was 6.10%. In multivariate analysis age 50 years and older (odds ratio [95% C.I.]: 2.91 [1.32 - 6.41] for ages 50 - 59), ASA class of IV and above (4.07 [1.96 - 8.44]), and operative timing of 420 minutes and longer (2.43 [1.07 - 5.52] for 420 - 479 minutes; Figure 1) were predictive of any complication while the number of levels fused, anterior fusion, osteotomies, pelvic fixation, and perioperative transfusion were not statistically significant risk factors. Age 80 years and older (7.39 [1.79 - 30.50]), ASA class of IV and above (3.37 [1.18 - 9.63]), and operative timing of 480 minutes and longer (9.46 [1.79 - 49.95] for 480 - 549 minutes) were predictive of serious complications while the number of levels fused, anterior fusion, osteotomies, pelvic fixation, and perioperative transfusion were not statistically significant risk factors.

Conclusions: Operative time is a better predictor of perioperative complications than surgical invasiveness. Rather than avoidance of more invasive surgical procedures, such as longer posterior fusions, combined anterior and posterior fusions, and pelvic fixation, which have been shown to improve stability and long-term outcomes, it may be that emphasis should be place on reduction of overall operative time while still performing adequate deformity correction.

Figure 1