Table 4.
Proposed Definitions, Accuracy, and Reliability of Computed Tomography Findings of Thoracolumbar Posterior Ligamentous Complex Injury.
| CT criteria | Definition | Best imaging plane/Additional | PPV | NPV | Interobserver K |
Pearls /pitfalls |
|---|---|---|---|---|---|---|
| Vertebral body translation | Relative listhesis of a vertebra compared to infreadjacent vertebra in the sagittal or coronal plane. 39 | Midsagittal /coronal | 100 40 | 79 | .623 sagittal translation, .612 coronal translation 10 | Distinguish between translation and retropulsion fragment involving inferior endplate look at the facet management |
| Facet joint Malalignment | Unilateral or bilateral Facet (s) that were perched, dislocated, or fractured.12,24 | All planes | 94 12 | 76 | .656 dislocation, 10 .57 12 | Must be reviewed in all imaging planes. |
| Facet joint widening | Unilateral or bilateral widening ≥ 3 mm in the axial CT with no evidence of facet malalignment12,24 | Axial | 36 12 | 67 | .49 axial, .36 sagittal, 10 .45 12 | It should be distinguished as it has little predictive value for PLC injury |
| Horizontal laminar fracture | Horizontally-oriented fracture (in the coronal plane) of the lamina, pars /or pedicles, whether unilateral or bilateral 35 | Coronal | 91 12 | 81 | .76 34 | Distinguish between horizontal and vertical laminar fracture best in coronal view |
| Vertical laminar fracture | Vertically oriented fracture (in the coronal plane) of the lamina located between the medial borders of both pedicles, with or with or without spinous process involvement.35,41 | Coronal | 29 12 | 65 | .91 35 | Sometimes vertical split involves the base of the spinous process: this should not be considered a spinous process fracture |
| Spinous process fracture | Avulsion or transverse fracture of the spinous process12,24 | Midsagittal/coronal | 86 12 | 81 | .89 12 | Avoid missing a tiny avulsion fracture |
| Interspinous widening | Widening of interspinous distance > 4 mm compared to the adjacent levels.12,24 | Midsagittal | 59 12 | 78 | .303, 10 .63 12 | In case of coronal plane deformity, measure it in the coronal plane |
Abbreviations: CT, Computed tomography; PPV, Positive predictive value; NPV, Negative predictive value; K, Kappa Coefficient.