Purpose: The skeleton is the third most common site of cancer metastases. Approximately 10 % of patients with bone metastases will develop a pathologic fracture, with significant associated morbidity and mortality. The purpose of this study was to identify risk factors for same-admission mortality after pathologic fractures secondary to metastatic cancer.
Methods: The Nationwide Inpatient Sample database was queried from 2002 to 2013 for hospitalized patients with diagnoses of pathologic fracture and a primary cancer at high risk for skeletal metastasis. Univariate and multivariate analyses were performed to determine risk factors associated with same-admission mortality after fracture.
Results: A total of 371,163 patients were identified. The spine was the most common site of pathologic fracture (68.0 %) followed by lower extremity (25.0 %) and upper extremity (8.7 %). The following factors were independently associated with increased mortality (p < 0.001): cancer of lung or unspecified location; fracture of upper or lower extremity; male gender; age ≥65; non-Medicare insurance; coexisting congestive heart failure, chronic pulmonary disease, renal failure, or liver disease; and postoperative surgical site infection, acute myocardial infarction, pulmonary embolism, or pneumonia. Closed reductions were associated (p < 0.001) with increased mortality while open or percutaneous surgical treatments were protective (p < 0.001) against mortality.
Conclusions: Pathologic fractures are a devastating consequence of metastatic bone disease, contributing significantly to morbidity and mortality. Numerous demographic and medical factors are associated with increased same-admission mortality. This data is useful for counseling patients with skeletal metastatic disease and should be taken into consideration when conducting routine skeletal surveillance in patients with metastatic cancer.
Keywords: Musculoskeletal oncology; NIS; National Inpatient Sample; Neoplasm metastasis; Orthopedics; Spontaneous fractures.