Purpose: To examine the morphologic alterations of fractures of the lateral and anterior rib arcs and costochondral junction (CCJ) to better understand the factors that influence radiographic visualization and to gain insight into the mechanism of injury in rib fractures of abused infants.
Materials and methods: Thirty-one infants (average age, 3 months) who died with inflicted skeletal injuries were studied with high-detail, pre- or postmortem skeletal surveys, or both, and radiography of specimens, with histologic analysis. The distribution and number of fractures were determined for each technique, and dating was performed on the basis of radiographic and histologic criteria. The radiologic features were correlated with the pathologic findings in comparable histologic sections.
Results: Of 165 fractures, 84 (51%) involved the ribs. Only 30 rib fractures (36%) were visible with skeletal survey examination. Lateral and anterior arc fractures tended to impact along the inner cortex of the rib. CCJ fractures tended to involve the inner aspect of the osteochondral interface with an associated osseous fragment.
Conclusion: Acute and healing rib fractures are common in infants who died with inflicted injury; detection is technique-dependent. Use of high-detail skeletal radiography to identify these injuries in live and deceased infants appears justified.