Evaluation of Rod Breakage After Three-Column Osteotomy

Abstract

Objective: To identify the incidence and possible risk factors associated with rod breakage in patients who underwent vertebral column resection (VCR) or pedicle subtraction osteotomy (PSO) to treat complex deformities of the spine. Methods: Retrospective analysis of a series of 32 patients operated from 2014 to 2018 in a single center. The patients were analyzed for demographic (sex, age), biometric (BMI), radiographical (pre-and postoperative angular variations), and surgical (arthrodesed and osteotomized levels) characteristics. Descriptive analyses were performed for the numerical variables (mean, standard deviation, maximum, median, and minimum) and frequency analysis was performed for the categorical variables. Logistic regression analysis was performed for the dependent variable "rod breakage", using a stepwise technique to select the variables for the best model, assuming statistical significance of 0.05. Results: Of the 32 patients selected, rod breakage occurred in 34.4%. Mean age was 36.6 years (± 19.8), ranging from 10 to 74 years, and the mean BMI was 25.1 (±6.0). Most patients were subjected to VCR (75.0%), were males (56.2%) and did not smoke (90.6%). Logistic regression analysis showed that "arthrodesed levels" were was positively associated with rod breakage (OR 1.72; CI95%: 1.13-3.10; p<0.05). The other factors were not associated with breakage. Conclusion: Rod breakage is a frequent complication after three-column osteotomy, especially in long constructions. Level of evidence III; Retrospective Study.