Are We Underestimating the Morbidity of Single Rib Fractures?

Previous studies suggest that patients with multiple rib fractures have poor outcomes, but it is unknown how isolated single rib fractures (SRF) are associated with morbidity or mortality. We hypothesized that patients with poor outcomes after SRF can be identified by demographics and comorbidities. The purpose of this study was to model adverse outcome after single rib fractures.

We used the 2016 National Inpatient Sample to identify patients with SRF associated with blunt trauma using ICD-10 coding. Comorbidities and abbreviated injury score (AIS) were also extracted. Patients with non-chest trauma were excluded. The primary outcome was an adverse composite outcome of death, pneumonia, tracheostomy, or hospitalization longer than twelve days. One-third of the cohort was reserved for validation. Backward selection multivariable modeling identified factors associated with adverse composite outcome. The model was used to create a nomogram to predict adverse composite outcome. The nomogram was then tested using the validation cohort.

2,398 patients with isolated SRF were divided into training (n = 1,598) and validation sets (n = 800). The average age was 69 and the majority were male (66%) and received care at academic institutions (61.6%). The adverse composite outcome occurred in 20.8%: 61 deaths (2.5%), 67 tracheostomies (2.8%), 319 pneumonias (13.3%), and 165 patients with hospital length of stay greater than twelve days (6.9%). Results of stepwise multivariable modeling had a C-statistic of 0.700. The multivariable model was used to create a nomogram which had a c-statistic of 0.672 in the validation cohort.

20% of isolated SRF patients had an adverse outcome. Demographics and comorbidities can be used to identify and triage high-risk patients for specialized care and proper counseling.