Table 6.
Associations between MRI finding in the SIJ and the diagnosis of AS and IBP
| MRI findings | Sensitivity of MRI findings (95% CI) |
Specificity of MRI findings (95% CI) |
Cases, number | Controls, number | ||
|---|---|---|---|---|---|---|
| AS | IBP | NLSBP | No LBP | |||
| BMO | 0.85 (0.76-0.92) | 0.93 (0.84-0.97) | 75 | 59 | ||
| Erosions | 0.91 (0.82-0.95) | 0.98 (0.91-1.00) | 75 | 59 | ||
| Fat infiltration | 0.91 (0.82-0.95) | 0.86 (0.76-0.93) | 75 | 59 | ||
| Ankylosis | 0.27 (0.18-0.38) | 1.00 (0.94-1.00) | 75 | 59 | ||
| Global assessment | 0.99 | 0.96 | 75 | 59 | ||
| BMO | 0.85 (0.76-0.92) | 0.77 (0.58-0.89) | 75 | 26 | ||
| Erosions | 0.91 (0.82-0.95) | 0.96 (0.81-0.99) | 75 | 26 | ||
| Fat infiltration | 0.91 (0.82-0.95) | 0.85 (0.67-0.94) | 75 | 26 | ||
| Ankylosis | 0.26 (0.18-0.38) | 1.00 (0.87-1.00) | 75 | 26 | ||
| Global assessment | 0.99 | 0.92 | 75 | 26 | ||
| BMO | 0.67 (0.48-0.81) | 0.93 (0.84-0.97) | 27 | 59 | ||
| Erosions | 0.48 (0.31-0.66) | 0.98 (0.91-1.00) | 27 | 59 | ||
| Fat infiltration | 0.37 (0.22-0.56) | 0.86 (0.76-0.93) | 27 | 59 | ||
| Global assessment | 0.52 | 0.96 | 27 | 59 | ||
| BMO | 0.67 (0.48-0.81) | 0.77 (0.58-0.89) | 27 | 26 | ||
| Erosions | 0.48 (0.31-0.66) | 0.96 (0.81-0.99) | 27 | 26 | ||
| Fat infiltration | 0.37 (0.22-0.56) | 0.85 (0.67-0.94) | 27 | 26 | ||
| Global assessment | 0.52 | 0.92 | 27 | 26 | ||
Results from Weber et al. (2010). Sensitivity and specificity based on concordant observations of a minimum of two of five readers. 95% CI calculated from raw data. MRI, magnetic resonance imaging; SIJ, sacroiliac joint; AS, ankylosing spondylitis; IBP, inflammatory back pain; CI, confidence interval; NSLBP, nonspecific low-back pain; BMO, bone marrow edema; global assessments, 95% CI not possible to calculate, because of no raw data.