Table 2.
Structural properties of lumbar and coccygeal intervertebral discs from young and old mice
| Compression-Tension |
Creep |
||||||||
|---|---|---|---|---|---|---|---|---|---|
| Age and Region | ROM, mm | STEN, N/mm | SCOM, N/mm | SNZ, N/mm | Deform, mm | S1, N/mm | S2, N/mm | η1, N·s/mm | η2, N·s/mm |
| Lumbar | |||||||||
| Young | 0.12 ± 0.05 | 18 ± 8 | 26 ± 11 | 4 ± 2 | 0.11 ± 0.03 | 26 ± 7 | 8 ± 2 | 1,483 ± 633 | 6,090 ± 2,259 |
| Old | 0.19 ± 0.05* | 10 ± 4* | 21 ± 7 | 2 ± 2 | 0.12 ± 0.04 | 29 ± 16 | 9 ± 5 | 890 ± 301* | 6,460 ± 5,165 |
| Coccygeal | |||||||||
| Young | 0.23 ± 0.07 | 25 ± 8 | 43 ± 11 | 2 ± 2 | 0.23 ± 0.03 | 30 ± 10 | 9 ± 3 | 2,047 ± 751 | 6,598 ± 2,337 |
| Old | 0.23 ± 0.05 | 35 ± 12* | 44 ± 17 | 3 ± 3 | 0.18 ± 0.07 | 45 ± 22* | 14 ± 7 | 3,150 ± 1,451* | 11,200 ± 7,975 |
Values are means ± SD. ROM, range of motion; STEN, tensile stiffness; SCOM, compression stiffness; SNZ, neutral zone stiffness; S1 and S2, elastic coefficients at early and late creep displacement, respectively; η1 and η2, viscous coefficients at early and late creep displacement, respectively.
*
Young vs. old, P < 0.05.