Chest CT imaging utility for radiographically occult rib fractures in elderly fall-injured patients

BACKGROUND Previous studies demonstrate an association between rib fractures and morbidity and mortality in trauma. This relationship in low-mechanism injuries such as ground-level fall is less clearly defined. Furthermore, computed tomography (CT) has increased sensitivity for rib fractures compared with chest x-ray (CXR); its utility in elderly fall patients is unknown. We sought to determine whether CT-diagnosed rib fractures in elderly fall patients with a normal CXR were associated with increased in-hospital resource utilization or mortality.
METHODS Retrospective analysis of emergency department patients presenting over a 3-year period.
INCLUSION CRITERIA age ≥ 65, chief complaint including mechanical fall, and both CXR and CT obtained. We quantified rib fractures on CXR and CT and reported operating characteristics for both. Outcomes of interest included hospital admission/length-of-stay (LOS), ICU admission/LOS, endotracheal intubation, tube thoracostomy, loco-regional anesthesia, pneumonia, in-hospital mortality.
RESULTS We identified 330 patients, mean age 84 years (±SD 9.4); 269/330 (82%) admitted. There were 96 (29%) patients with CT-diagnosed rib fracture, 56 (17%) by CT only. Compared to CT, CXR had a sensitivity of 40% (95% CI 30-50%) and specificity of 99% (95% CI 97-100%) for rib fracture. A median of 2 additional radiographically occult rib fractures were identified on CT. Despite an increased hospital admission rate (91% vs 78%) p=0.02, there was no difference between patients with and without radiographically occult (CT+ CXR-) rib fracture(s) for: median LOS (4 [IQR 2-7] vs 4 [2-8]) p=0.92, ICU admission (28% vs 27%) p=0.62, median ICU LOS (2 [1-8] vs 3 [1-5]) p=0.54, or in-hospital mortality (10.3% vs 7.3%) p=0.45.
CONCLUSIONS Among elderly fall patients, CT-identified rib fractures were associated with increased hospital admissions. However, there was no difference in procedural interventions, ICU admission, hospital/ICU LOS or mortality for patients with and without radiographically occult fractures.
LEVEL OF EVIDENCE Level III, Diagnostic Tests or Criteria.

as reported in: J Trauma Acute Care Surg. 2019 Jan 23 [Epub ahead of print]