Fig 1.
The location of a needle in the intervertebral disc was evaluated using micro-computed tomography scanning.
(a) The punctured region was confirmed by multiplanar reconstruction views. (b) The punctured region was defined as the ventral (V), central (C), or dorsal (D) region.
Fig 2.
The novel proposed histological grading score.
Arrows indicate the serpentine findings in the annulus fibrosus.
Fig 3.
The flowchart of the experiment indicating the time course and the case number.
V, ventral region; C, central region; D, dorsal region.
Fig 4.
The comparison of the histological classifications.
The distribution of scores in each classification. Red brackets indicate the minimum ranges that include 50% of the data. The red and black dots of the classification score of Nishimura et al.[22] indicate the outliers.
Fig 5.
Correlation analysis between our histological score and MRI index.
The blue, black, and red dots indicate the ventral, dorsal, and central region cases, respectively. Ovals indicate 50% confidence ellipse with bivariate normal distribution of each region.
Table 1.
Multiple regression analysis to identify significant variable for the degenerative intervertebral discs.
Table 2.
Punctured region and intervertebral disc degeneration compared to the control.
Fig 6.
Punctured region and intervertebral disc degeneration.
Representative magnetic resonance imaging and histological images at four weeks after puncturing with 35- and 33-gauge needles.
Fig 7.
The mid-sagittal slice of the lumbar intervertebral disc (IVD).
The nucleus pulposus (NP) center was deviated dorsally relative to the IVD center. In 77 intact mouse lumbar IVDs, the width of ventral annulus fibrosus (AF), the dorsal deviation of the NP center relative to the IVD center, and the width of dorsal AF were calculated as proportion relative to the major axis of the IVD. The average amount of NP deviation (7%) corresponded to the difference in width between the average ventral (28%) and the average dorsal AF (15%): the ventral site of AF is thicker compared to the dorsal site.
Table 3.
Intervertebral disc degeneration and needle size.
Table 4.
Intervertebral disc degeneration and needle size.