Predictors for Postoperative Loss of Lumbar Lordosis After Long Fusions Arthrodesis in Patients with Adult Scoliosis

BACKGROUND Loss of lumbar lordosis (LL) is closely related to clinical symptoms and operative complications, however, few studies have identified its predictors. The purpose of our study was to identify the predictors for loss of LL in patients with adult scoliosis and provided evidence for surgical decision-making. MATERIAL AND METHODS There were 69 patients with adult scoliosis who underwent long fusions arthrodesis from January 2006 to March 2015 included in this retrospectively study. The patients were divided into two cohorts according the average loss of LL: cohort LL (loss of LL below the average) and cohort GL (loss of LL above the average). Multivariate logistic regression analysis and the receiver operating characteristic curve were used to identify the predictors. RESULTS There were statistically significant differences between the two cohorts in preoperative LL (p=0.002), postoperative LL (p=0.036), last follow-up LL (p<0.001), postoperative loss LL (p<0.001), preoperative SVA (p=0.007), last follow-up SVA (p=0.018), and pelvic incidence (p=0.016). Preoperative LL <23.5 (OR=0.920, 95% CI=0.870-0.973, p=0.003) and preoperative sagittal vertical axis >4.28 (OR=1.199, 95% CI=1.007-1.429, p=0.041) had good accuracy to predict postoperative loss of LL. CONCLUSIONS Loss of LL commonly occurred after long fusions arthrodesis in patients with adult scoliosis. Postoperative deteriorated sagittal balance was more frequently than deteriorated coronal balance. Preoperative LL <23.5 and preoperative SVA >4.28 were the predictors for postoperative greater loss of LL in patients after long fusions arthrodesis. More attention should be paid to how to maintain the LL in patients with preoperative predictors, especially if both the identified predictors are present.