Risk Factors for Cement Leakage in Cement-Augmented Pedicle Screw Fixation: A Multicenter Study of 140 Patients and 650 Screws.

Abstract

Study DesignMulticenter retrospective cohort study.ObjectivesCement-augmented pedicle screws (CAPS) enhance fixation in osteoporotic patients, but carry a risk of cement leakage (CL), potentially leading to pulmonary embolism and neurological deficits. This study aimed to investigate the incidence and classification of CL and identify risk factor.MethodsWe included 140 patients undergoing thoracic or lumbar spinal fusion with CAPS at 7 institutions. CL was assessed by postoperative CT and classified as type S (segmental vein), type B (basivertebral vein), or type I (malpositioned screws). Multivariate logistic regression was performed to identify independent risk factors for intravenous CL.ResultsCL was observed in 88/140 patients (62.9%) and 190/650 screws (29.2%). Type S leakage was most common (77.9%), followed by type B (11.6%) and type I (7.9%). No symptomatic pulmonary cement embolism occurred; however, 1 patient experienced CL-related nerve root injury. Lower femoral neck T-score (aOR: 0.61; <i>P</i> = 0.009) was an independent risk factor for intravenous CL, while diffuse idiopathic skeletal hyperostosis was protective (aOR: 0.24; <i>P</i> = 0.009). Type S leakage was associated with shorter distance from the cement hole to the vertebral sidewall (aOR: 0.77; <i>P</i> < 0.001) and smaller vertebral body cross-sectional area (aOR: 0.87; <i>P</i> = 0.030). Type B leakage was associated with shorter distance to the vertebral posterior wall (aOR: 0.71; <i>P</i> < 0.001) and lower pedicle Hounsfield units (aOR: 0.99; <i>P</i> = 0.041).ConclusionsAsymptomatic CL was frequently observed following CAPS fixation. Preoperative imaging assessments and precise screw placement may reduce the CL risk.