Trauma characteristics and associations with the predictive values for MRI abnormalities in patients aged 18–45 years and recent knee trauma seen in primary care, N = 174
| Trauma characteristics | Yes/No | n | ACL rupture | Traumatic meniscal tear | Positive MRI finding(s)a | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| n= 38 (22%) | n= 26 (15%) | n= 67 (39%) | |||||||||
| OR (95% CI) | NPV | PPV | OR (95% CI) | NPV | PPV | OR (95% CI) | NPV | PPV | |||
| Sports-related trauma | yes | 105 | 3.7 (1.5 to 9.0) | 90 | 30 | 3.2 (1.1 to 8.9) | 93 | 20 | 4.6 (2.2 to 9.3) | 81 | 51 |
| no | 69 | ||||||||||
| Rotational trauma | yes | 70 | 1.1 (0.5 to 2.3) | 79 | 23 | 1.9 (0.8 to 4.4) | 88 | 20 | 2.0 (1.1 to 3.8) | 68 | 49 |
| no | 104 | ||||||||||
| Popping sound | yes | 64 | 3.1 (1.5 to 6.5) | 85 | 34 | 3.3 (1.4 to 7.9) | 91 | 25 | 2.1 (1.1 to 4.0) | 68 | 50 |
| no | 113 | ||||||||||
| Direct pain | yes | 127 | 3.9 (1.3 to 11.8) | 91 | 26 | 2.3 (0.7 to 6.9) | 91 | 17 | 3.0 (1.4 to 6.6) | 79 | 45 |
| no | 47 | ||||||||||
| Direct swelling | yes | 43 | 1.6 (0.7 to 3.5) | 80 | 28 | 1.1 (0.4 to 2.9) | 85 | 16 | 2.0 (1.0 to 4.0) | 66 | 51 |
| no | 131 | ||||||||||
| Inability to continue activity | yes | 124 | 2.6 (1.0 to 6.6) | 88 | 26 | 1.4 (0.5 to 3.8) | 88 | 16 | 2.5 (1.2 to 5.3) | 76 | 44 |
| no | 50 | ||||||||||
| Combinations | |||||||||||
| Popping sound and direct swelling | yes | 17 | 2.8 (1.0 to 8.1) | 80 | 41 | 3.7 (1.2 to 11.2) | 87 | 35 | 3.3 (1.2 to 9.4) | 64 | 65 |
| no | 157 | ||||||||||
| Rotational trauma and direct swelling | yes | 21 | 1.5 (0.5 to 4.2) | 79 | 29 | 0.6 (0.4 to 4.6) | 86 | 19 | 3.0 (1.2 to 7.6) | 65 | 62 |
| no | 153 | ||||||||||
↵a Positive MRI findings: trabecular fracture, traumatic meniscal tear, cruciate ligament rupture, complete rupture collateral ligament and/or a full thickness cartilage defect. ACL = anterior cruciate ligament. OR = odds ratio. NPV = negative predictive value. PPV = positive predictive value, both expressed in percentages.