Utility of the ACS‐NSQIP surgical risk calculator in predicting postoperative complications in patients undergoing oncologic proximal femoral replacement

Introduction Proximal femur replacement (PFR) in the setting of tumor resection is associated with a high rate of postoperative complication. The online American College of Surgeons‐National Surgical Quality Improvement Program (ACS‐NSQIP) surgical risk calculator is approved by the Center of Medicare and Medicaid services to estimate 30‐day postoperative complications. This study was to determine if the ACS‐NSQIP can predict postoperative complications following PFR. Methods We reviewed 103 (61 male and 42 female) patients undergoing PFR using the Current Procedural Terminology (CPT) codes available in the calculator: 27125 (hemiarthroplasty), 27130 (total hip), 27132 (conversion to total hip), 27134 (revision total hip), 27137 (revision acetabulum), 27138 (revision femur), and 27365 (excision tumor hip). The predicted rates of complications were compared with the observed rates. Results Complications occurred in 54 (52%) of patients, with the predicted risk based on CPT codes: 27125 (21.5%); 27130 (7.8%); 27132 (16.6%), 27134 (17.8%), 27137 (14.4%), 274138 (22.7%), and 27365 (16.2%). The calculator was a poor predictor of complications (27125, area under the curve [AUC] 0.576); (27130, AUC 0.489); (27132, AUC 0.490); (27134, AUC 00.489); (27137, AUC 0.489); (27138, AUC 0.471); and (27365, AUC 0.538). Conclusion Oncologic PFR is known for complications. The ACS‐NSQIP does not adequately predict the incidence of complications, and therefore cannot reliably be used in their shared decision‐making process preoperative.