Table 5.
Performance of MRI in various degrees of ligamentous injury.
| Degree of injury | Ligament | Sensitivity/% (95% CI) | Specificity/% (95% CI) | PPV (95% CI) | NPV (95% CI) | Accuracy |
|---|---|---|---|---|---|---|
| Normal | ATFL | 0 (0–94) | 86 (77–93) | 0 (0–32) | 99 (91–100) | 85 |
| CFL | 85 (65–91) | 56 (42–69) | 49 (34–64) | 89 (72–96) | 66 | |
| Partial tear | ATFL | 64 (49–78) | 86 (70–95) | 85 (68–94) | 67 (51–79) | 74 |
| CFL | 41 (25–58) | 87 (73–94) | 71 (48–88) | 64 (51–76) | 66 | |
| Complete tear | ATFL | 78 (60–89) | 80 (66–90) | 76 (58–88) | 82 (67–91) | 79 |
| CFL | 61 (36–81) | 95 (86–99) | 79 (49–94) | 90 (79–95) | 88 |
ATFL = anterior talofibular ligament; CFL = calcaneofibular ligament; CI = confidence interval; MRI = magnetic resonance imaging; NPV = negative predictive value; PPV = positive predictive value.