Detection of Costal Cartilage Fractures on CT Images With Computer-aided Detection System for Rib Fractures

Costal cartilage fractures are associated with poor prognosis in patients with blunt chest trauma. A Computer-Aided Detection (CAD) system for detecting rib fractures has been used in practice, but it is unclear whether this system recognizes costal cartilage fractures. This study investigated whether the CAD system for rib fracture can detect costal cartilage fractures.

A total of 89 patients with costal cartilage fractures from participating hospitals over an 18-year period were included in the study. The presence of a costal cartilage fracture was determined by three radiologists. We reviewed fracture location, cartilage calcification, dislocation, and callus formation. The percentage of agreement between the radiologists and the CAD system (Rib fracture CAD, Fujifilm Medical Co., Ltd) was assessed.

We detected 246 costal cartilage fractures in 89 patients. The costal cartilage of rib 7 was injured most frequently. Costal cartilage fractures were categorized as either mid-chondral, costochondral, or chondro-sternal. The CAD system detected 33 lesions; 16 were consistent with the costal cartilage fractures determined by the radiologists (costochondral junction 13, mid-chondral 2, chondro-sternal 1).

The CAD system for rib fracture can detect costal cartilage fractures at the costochondral junction but is not sufficiently sensitive to detect costal cartilage fractures without calcification. The CAD system for rib fracture needs further development before it can be used to detect rib cartilage fractures.