Published online Jan 18, 2022. doi: 10.5312/wjo.v13.i1.87
Peer-review started: June 14, 2021
First decision: October 18, 2021
Revised: November 2, 2021
Accepted: January 5, 2022
Article in press: January 5, 2021
Published online: January 18, 2022
Processing time: 216 Days and 19.2 Hours
The response to axial physiological pressure due to load transfer to the lumbar spine structures is among the various back pain mechanisms. Understanding the spine adaptation to cumulative compressive forces can influence the choice of personalized treatment strategies.
To analyze the impact of axial load on the spinal canal’s size, intervertebral foramina, ligamenta flava and lumbosacral alignment.
We assessed 90 patients using three-dimensional isotropic magnetic resonance imaging acquisition in a supine position with or without applying an axial compression load. Anatomical structures were measured in the lumbosacral region from L1 to S1 in lying and axially-loaded magnetic resonance images. A paired t test at α = 0.05 was used to calculate the observed differences.
After axial loading, the dural sac area decreased significantly, by 5.2% on average (4.1%, 6.2%, P < 0.001). The intervertebral foramina decreased by 3.4% (2.7%, 4.1%, P < 0.001), except for L5-S1. Ligamenta flava increased by 3.8% (2.5%, 5.2%, P < 0.001), and the lumbosacral angle increased.
Axial load exacerbates the narrowing of the spinal canal and intervertebral foramina from L1-L2 to L4-L5. Cumulative compressive forces thicken ligamenta flava and exaggerate lumbar lordosis.
Core Tip: In this study, a statistically proven correlation was made between the axial loading and lumbar spinal stenosis, thickening of the ligamenta flava, narrowing of the intervertebral foramina from L1-L2 to L4-L5 and lumbar lordosis exaggeration. A novel aspect of this study was a simultaneous comparison of the dural sac size, ligamenta flava thickness, foraminal dimensions and lumbar sagittal alignment between axial loaded and recumbent three-dimensional high-resolution magnetic resonance imaging in an extensive group of lower back pain patients. This was done to conduct a detailed evaluation for better spinal surgery decision-making and spinal injections.