Article Figures & Data
Figures
- Fig 1.
For the L2 vertebral body, the facet joint signal-change score (0–16) is the sum of the facet joint signal-change grades of each of the 4 associated facet joints (0–4). Anatomically, the L2 vertebral body–associated facet joints are shared with the adjacent vertebral bodies. Therefore, the L2-associated facet joints could be subject to stress from compression fractures of the L2 or adjacent L1 and L3 vertebral bodies. For the L2 level, the above facet joint signal-change score for the L1/L2 and L2/L3 facet joints of patients with an acute/subacute compression fracture of L1, L2, and/or L3 was compared with the facet joint signal-change score for the L1/L2 and L2/L3 facet joints of patients without an acute/subacute compression fracture at L1, L2, or L3. This same method was then applied to the remaining lumbar vertebrae.
- Fig 2.
Level-by-level distribution of acute/subacute vertebral body compression fractures, chronic compression fractures, and prior vertebral augmentation.
- Fig 3.
Facet joint inflammatory changes are more prevalent at levels of acute/subacute compression fracture than in levels without such fracture. A 66-year-old woman presented with an acute/subacute L4 compression fracture. Sagittal fat-saturated T2-weighted images demonstrate facet edema of the left (A) and right (B) L3/L4 and L4/5 facet joints. There was no facet joint inflammatory change associated with the remaining lumbar facet joints (images not shown).
- Fig 4.
Level-by-level distribution of the degree of vertebral body height loss.
Tables
- Table 1:
Grading of facet joint inflammation using fat-saturated MRI signal characteristicsa
Grade 0 No signal abnormality 1 Signal abnormality limited to joint capsule 2 Periarticular signal abnormality involving <50% of the facet joint perimeterb 3 Periarticular signal abnormality involving >50% of the facet joint perimeter 4 Grade 3 with additional signal abnormality within the neural foramen, pedicle, ligamentum flavum, transverse process, or vertebral bodyc ↵a Grading scale adapted from Czervionke and Fenton.6
↵b Periarticular signal abnormality includes T2 hyperintensity or gadolinium enhancement on T1-weighted images.
↵c Signal abnormality within the pedicle must be continuous with other perifacet signal abnormalities and cannot represent posterior extension of vertebral body edema.
- Table 2:
Facet joint signal-change scores of acute/subacute lumbar levels compared with other levels
Facet Joint Signal-ChangeScorea Acute/subacute (mean) (SD) 2.2 (3.3) 2.6 (3.3) 3.7 (3.7) 4.6 (5.2) 4.8 (5.3) Other (mean) (SD)b 0.0 (0.0) 0.3 (0.9) 1.0 (2.3) 1.2 (2.5) 0.4 (0.9) P valuec <.01 .01 <.01 <.01 <.01 ↵a A vertebral body was considered influenced by an acute or subacute fracture if either the body of interest or an adjacent vertebral body was fractured.
↵b “Other” is used to denote the complement to this case, namely vertebral bodies with no fracture or nearby fracture. Vertebral bodies with a chronic compression fracture could be considered “other” if there were no adjacent acute/subacute fractures.
↵c Wilcoxon rank sum test.
- Table 3:
Facet joint signal-change score versus degree of height loss for patients with acute/subacute fractures
L1 (n = 75) L2 (n = 75) L3 (n = 75) L4 (n = 75) L5 (n = 75) Spearman rank correlation (ρ) 0.41 0.15 0.02 0.22 0.14 P value <.01 .21 .84 .05 .22
