Establishment of Scoring to Predict Severe Complication After Pyogenic Spondylodiscitis Surgery

Study Design: Retrospective cohort study using prospective database. Objective: This study aimed to establish a risk-scoring system for predicting severe complications after pyogenic spondylodiscitis surgery. Summary of Background data: Pyogenic spondylodiscitis surgery can cause severe complications. Methods: Grades III, IV, and V complications in the CD classification were defined as severe complications. A predictive scoring system for severe complications was developed using 7 risk factors identified from a cohort of 143 PS surgery patients from January 2013 to December 2017 described in a previous study. External validation used a separate cohort of 70 patients from 9 institutions identified from January 2018 to December 2021. Results: This first study proposed a risk predictive scoring system for severe complications [updated Charlson comorbidity index (≥3), 2; chronic pulmonary disease, 3; diabetes, 1; Gram-negative bacteria, 3; pyogenic osteoarthritis, 3; preoperative white blood count (≥1.0×10 4 /μL), 2; preoperative platelet count (≤2.4×10 5 /μL), 2]. The scoring system could well predict severe complications [area under the receiver operating curve (AUROC) value of 0.851]. There was classification into 3 risk groups: low–moderate risk (≤4), high risk (5 or 6), and very high risk (≥7), further simplified by the scoring system. Complication rates were 5.2% (low–moderate), 40.1% (high), and 84.2% (very high). In addition, external validation showed a very good AUROC value of 0.820. Conclusions: We developed a simple, externally validated scoring system for predicting severe complications after pyogenic spondylodiscitis surgery that will be helpful for clinicians involved in informed consent and intensive care unit management of high-risk patients.