Radiologic findings per vertebral level
| Variable | L1-L2 | L2-L3 | L3-L4 | L4-L5 | L5-S1 |
|---|---|---|---|---|---|
| CTF nomenclature | |||||
| Intravertebral herniation (yes)a | 64 (24.2) | 60 (22.6) | 58 (21.9) | 53 (20.0) | 56 (21.1) |
| Disk contoura | |||||
| Normal | 225 (84.9) | 183 (69.1) | 137 (51.7) | 64 (24.2) | 112 (42.3) |
| Bulging (>50%) | 30 (11.3) | 67 (25.3) | 108 (40.8) | 136 (51.3) | 72 (27.2) |
| Protrusion focal (<25%) | 8 (3.0) | 6 (2.3) | 16 (6.0) | 53 (20.0) | 47 (17.7) |
| Protrusion broad-based (25%–50%) | 2 (0.8) | 5 (1.9) | 4 (1.5) | 5 (1.9) | 22 (8.3) |
| Extrusion | 0 (0.0) | 4 (1.5) | 0 (0.0) | 7 (2.6) | 12 (4.5) |
| Nordic nomenclature | |||||
| Intravertebral herniation (yes)a | 50 (18.9) | 46 (17.4) | 52 (19.6) | 36 (13.6) | 24 (9.1) |
| Disk contoura | |||||
| Normal | 217 (81.9) | 204 (77.0) | 160 (60.4) | 84 (31.7) | 104 (39.2) |
| Bulging | 45 (17.0) | 46 (17.4) | 97 (36.6) | 137 (51.7) | 98 (37.0) |
| Protrusion | 3 (1.1) | 11 (4.2) | 8 (3.0) | 39 (14.7) | 60 (22.6) |
| Extrusion | 0 (0.0) | 4 (1.5) | 0 (0.0) | 5 (1.9) | 3 (1.1) |
a No. (%). All of the percentages are calculated over a total of 265 images (53 images seen by the 5 radiologists).