Lumbar Spine Demographic.
| DRG Size (mm) | Left | Right | ||||||||
| L1 | L2 | L3 | L4 | L5 | L1 | L2 | L3 | L4 | L5 | |
| Width: mean | 3.2 | 4.3 | 4.9 | 6.1 | 6.5 | 3.2 | 4.3 | 4.9 | 6.1 | 6.5 |
| Width: sem | 0.7 | 0.4 | 0.3 | 0.4 | 0.5 | 0.7 | 0.4 | 0.3 | 0.4 | 0.5 |
| DRG Region | Left | Right | ||||||||
| L1 | L2 | L3 | L4 | L5 | L1 | L2 | L3 | L4 | L5 | |
| Zone: mean | 3.0 | 3.0 | 3.5 | 3.9 | 4.3 | 3.0 | 3.1 | 3.5 | 3.8 | 4.2 |
| Zone: sem | 0.3 | 0.1 | 0.1 | 0.1 | 0.1 | 0.3 | 0.2 | 0.1 | 0.1 | 0.1 |
| Intervertebral Foramina Size (mm) | Left | Right | ||||||||
| L1 | L2 | L3 | L4 | L5 | L1 | L2 | L3 | L4 | L5 | |
| AP: mean | 6.6 | 7.4 | 7.6 | 8.4 | 8.7 | 6.8 | 7.2 | 7.4 | 8.5 | 8.6 |
| AP: sem | 0.2 | 0.2 | 0.3 | 0.4 | 0.4 | 0.4 | 0.2 | 0.3 | 0.2 | 0.4 |
| PP: mean | 7.2 | 8.1 | 9.4 | 10.1 | 10.1 | 7.3 | 8.5 | 9.4 | 10.4 | 10.3 |
| PP: sem | 1.8 | 0.7 | 0.8 | 0.8 | 0.7 | 1.8 | 0.7 | 0.8 | 0.8 | 0.7 |
| Pedicle width (medial to lateral) (mm) | Left | Right | ||||||||
| L1 | L2 | L3 | L4 | L5 | L1 | L2 | L3 | L4 | L5 | |
| Width: mean | 7.0 | 7.0 | 7.8 | 8.7 | 9.7 | 6.7 | 7.1 | 7.9 | 8.9 | 9.7 |
| Width: sem | 0.3 | 0.3 | 0.2 | 0.3 | 0.4 | 0.2 | 0.3 | 0.2 | 0.4 | 0.4 |
| Nerve Root Angle | Left | Right | ||||||||
| L1 | L2 | L3 | L4 | L5 | L1 | L2 | L3 | L4 | L5 | |
| Angle (rounded to nearest 10th) | 50.5 | 52.2 | 55.2 | 57.4 | 58.8 | 50.5 | 52.2 | 55.2 | 57.2 | 56.3 |
Key: DRG Region zone 1 and 2: intraspinal; zone 3: medial neuroforamina; zone 4: lateral neuroforamina; zone 5: extraforaminal space. Intervertebral Foraminal Size. Anteriorposterior (AP): maximal distance from posterior body/disk to facet joint. Pedicle to pedicle (PP) distance: inferior border of upper to superior border of lower pedicle. SEM: standard error of the mean. Angle determined via sin(O) = right/diagonal.