What, if any, is the location of the abnormality? A) no acute abnormality B) pneumothorax C) aortic injury D) pulmonary contusion E) none of the above
E) None of the above. There is no pneumo- or hematothorax, no mediastinal widening, no evidence of pulmonary contusion. However, the left paraspinal line bulges laterally near the diaphragm, caused by hematoma adjacent to T12. In the context of trauma, this finding makes a vertebral fracture very likely.
What is the left paraspinal line?
The left paraspinal line is formed by the interface between the paravertebral soft tissues (pleura with the posterior mediastinal fat, left paraspinal muscles and adjacent soft tissues) and the adjacent left lung. Associated with a positive Mach band phenomenon, its appearance on any frontal CXR is that of a line etched in white.
Please name further direct or indirect fracture signs that can be encountered on the AP view.
Abnormal widening of the distance between the pedicles and fracture(s) of transverse process(es) are other important things to look for on the AP view.
The soft tissue shadow of the left paraspinal line bulges near the diaphragm. Following trauma this finding is consistent with localized hematoma i.e. an indirect sign of a vertebral fracture.
No mediastinal widening, no evidence of pulmonary contusion, pneumo- or hematothorax, no further evidence of fracture or dislocation.
Conclusion
Lower thoracic vertebral fracture probable.