Normal Cervical Wedge Compression Fracture Size on X-Ray & CT
A cervical wedge compression fracture occurs when axial loading or flexion forces reduce the anterior vertebral body height relative to the posterior height. Accurate measurement of this height difference on lateral imaging is essential for distinguishing a true compression fracture from normal developmental or positional variation. Prompt identification guides triage decisions, immobilization, and surgical planning in both pediatric and adult trauma patients.
Normal Reference Values
| Orientation | Location | Measurement |
|---|---|---|
| Lateral | Difference Between Posterior And Anterior Vertebral Height | <3 mm |
Clinical Significance
A difference between posterior and anterior vertebral body height of 3 mm or more on lateral projection raises concern for a pathological wedge compression fracture. In children, mild anterior wedging can be a normal developmental variant—particularly at C3–C5—making correlation with clinical findings and mechanism of injury critical before labeling a finding as traumatic.
When the threshold is exceeded, further cross-sectional imaging with CT is warranted to evaluate posterior element integrity, retropulsion of fragments, and canal compromise. MRI adds value in assessing posterior ligamentous complex disruption, which influences stability classification.
- Traumatic wedge compression fracture (flexion-distraction mechanism)
- Pathological fracture (metastatic disease, multiple myeloma, osteoporosis)
- Normal developmental anterior wedging in pediatric cervical spine
- Scheuermann-like changes with end-plate irregularity
- Pseudo-subluxation at C2–C3 or C3–C4 mimicking instability
Reference: Benson M, Fixsen J. Children’s Orthopaedics and Fractures. Springer Verlag. (2010).
Imaging Notes
On lateral radiography, the anterior and posterior vertebral body heights are measured at the mid-coronal plane of the affected level. Ensure the film is taken in neutral position with adequate cervical extension to avoid positional pseudo-wedging. A true lateral projection—without rotation—is mandatory, as obliquity artificially alters measured heights.
On CT, sagittal multiplanar reconstructions (MPRs) with bone kernel provide the most reliable measurements. Thin-slice acquisitions (≤1 mm) allow precise delineation of end-plate cortex. CT also identifies associated posterior column fractures, facet involvement, and fragment retropulsion that plain radiographs may underestimate, particularly in the lower cervical spine where overlying shoulders can degrade radiographic quality.