Table 3.
Association between intradiscal vacuum phenomena (VPs) and lumbar spinal stenosis
| A: Shape | MRI classification of lumbar spinal stenosis | Total | ||||
| A | B | C | D | |||
| VP (−) | Count (% raw) |
171 *
(81.8%) |
9 (4.3%) |
22 (10.5%) |
7 *
(3.3%) |
209 |
| Exp. Count | 147.5 | 13.1 | 31.3 | 17.1 | ||
| Corrected P-value |
< 0.0001 | 0.07 | 0.006 | < 0.0001 | ||
| Spot | Count (% raw) |
21 (61.8%) |
3 (8.8%) |
7 (20.6%) |
3 (8.8%) |
34 |
| Exp. Count | 24.0 | 2.1 | 5.1 | 2.8 | ||
| Corrected P-value |
0.23 | 0.51 | 0.34 | 0.89 | ||
| Linear | Count (% raw) |
21 (55.3%) |
4 (10.5%) |
5 (13.2%) |
8 *
(21.1%) |
38 |
| Exp. Count | 26.8 | 2.4 | 5.7 | 3.1 | ||
| Corrected P-value |
0.03 | 0.35 | 0.74 | 0.0022 | ||
| Island | Count (% raw) |
46 *
(53.5%) |
7 (8.1%) |
21 (24.4%) |
12 (14.0%) |
86 |
| Exp. Count | 60.7 | 5.4 | 12.9 | 7.0 | ||
| Corrected P-value |
0.0001 | 0.41 | 0.005 | 0.025 | ||
| B: Distribution | MRI classification of lumbar spinal stenosis | Total | ||||
| A | B | C | D | |||
| VP (−) | Count (% raw) |
171
#
(81.8%) |
9 (4.3%) |
22 (10.5%) |
7
#
(3.3%) |
209 |
| Exp. Count | 147.5 | 13.1 | 31.3 | 17.1 | ||
| Corrected P-value |
< 0.0001 | 0.07 | 0.006 | < 0.0001 | ||
| A-N | Count (% raw) |
41 (63.1%) |
5 (7.7%) |
9 (13.8%) |
10 (15.4%) |
65 |
| Exp. Count | 45.9 | 4.1 | 9.7 | 5.3 | ||
| Corrected P-value |
0.14 | 0.60 | 0.77 | 0.02 | ||
| N | Count (% raw) |
26 (53.1%) |
7 (14.3%) |
9 (18.4%) |
7 (14.3%) |
49 |
| Exp. Count | 34.6 | 3.1 | 7.3 | 4.0 | ||
| Corrected P-value |
0.0039 | 0.013 | 0.48 | 0.09 | ||
| N-P | Count (% raw) |
12
#
(44.4%) |
2 (7.4%) |
7 (25.9%) |
6 (22.2%) |
27 |
| Exp. Count | 19.1 | 1.7 | 4.0 | 2.2 | ||
| Corrected P-value |
0.0019 | 0.07 | 0.005 | 0.0001 | ||
| A-N-P | Count (% raw) |
9 (52.9%) |
0 (0%) |
8
#
(47.1%) |
0 (0%) |
17 |
| Exp. Count | 12.0 | 1.1 | 2.5 | 1.4 | ||
| Corrected P-value |
0.1 | 0.27 | 0.00015 | 0.21 | ||
The results of a contingency-table test are presented. A: VP shape analysis. B: VP distribution analysis. Percentages of the raw marginal total (% raw) are in parentheses. Exp. Count: expected count; VP (−): non-ruptured group; Nucleus pulposus: N; anterior annulus fibrosus: A; and posterior annulus fibrosus: P. *P < 0.0025, #P < 0.002 (by Bonferroni correction). The cells with counts above or below the expected count with statistical significance are shown in bold