Background
Pathologic features | Role of MRI |
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Ligamentous injury | • Higher sensitivity for detection compared to CT. • Complete tear (seen as discontinuity of ligaments) or partial tear (seen as abnormal signal) can be differentiated. • Helpful in guiding management by differentiating stable from unstable injuries. |
Disc damages and herniations | • Detection of abnormal disc signal related to traumatic herniations. • Important to diagnose this before closed reduction as undetected disc herniations can cause worsening cord injury. |
Extra medullary hemorrhage | • MRI shows extent of hematoma to help in surgical planning. • Extradural hematoma is commonly encountered and can lead to cord compression. |
Vascular injuries | • Enable detection of arterial injuries, which include an intimal flap, pseudoaneurysm, complete occlusion or active extravasation. • Undetected vascular injuries can cause spinal cord infarctions. |
Cord injuries | • Detection of hemorrhagic and non-hemorrhagic cord injuries. • This is the single most important role of MRI in spinal trauma evaluation. • Visualized as abnormal cord signal with hemorrhage best seen on gradient recalled echo (GRE) type sequences. • Presence of hemorrhage is the most important poor prognostic factor. |
Acute vs old vertebral fracture | • Age-indeterminate fractures identified on radiography and CT can be classified into acute and old fractures based on the presence or absence of bone marrow edema, respectively. |
Benign vs malignant fracture | • Differentiation of benign and malignant fractures. • Benign fractures show horizontal band of marrow edema, concave appearance of posterior vertebral margin and lack of soft tissue mass. • Malignant fractures show almost complete involvement of vertebral body, convex posterior margin and associated soft tissue mass. |