Table 1.
Unconfined compression equilibrium properties and relaxation for NP and potential replacement materials
| Material | Toe modulus (kPa) | Linear modulus (kPa) | Poisson’s ratio | Relaxation (%) |
|---|---|---|---|---|
| Human NP | 3.25 (1.56) | 5.39 (2.56) | 0.62 (0.15) | 65.77 (11.30) |
| Hydrogel A | 2.82 (1.19) | 6.97 (2.10) | 0.48 (0.24) | 19.86 (6.38)* |
| Hydrogel B | 7.91 (4.21)* | 21.90 (4.82)* | 0.59 (0.16) | 13.89 (4.71)* |
| Hydrogel C | 8.37 (1.61)* | 14.47 (0.63)* | 0.56 (0.13) | 30.67 (5.90)* |
| 1.2% lv alginate | n/a | 3.11 (1.73) | 0.43 (0.10)* | 98.23 (0.95)* |
| 1.0% mv alginate | 1.49 (0.64) | 5.45 (0.70) | 0.35 (0.07)* | 83.95 (1.72)* |
| 1.2% mv alginate | 6.72 (0.44) | 8.60 (2.29) | 0.33 (0.07)* | 86.58 (9.96)* |
| 2.0% mv alginate | 3.42 (1.89) | 7.46 (2.31) | 0.22 (0.04)* | 83.39 (4.72)* |
| 3.0% mv alginate | 5.02 (4.82) | 7.88 (5.15) | 0.15 (0.07)* | 78.14 (3.11)* |
| 4.0% mv alginate | 4.41 (1.05) | 13.02 (4.31)* | 0.17 (0.04)* | 82.95 (0.93)* |
| 2.0% mv agarose | n/a | 13.45 (1.53)* | 0.12 (0.03)* | 79.88 (2.12)* |
All values reported mean (SD)
lv low viscosity, mv medium viscosity
*Significantly different than human NP (P < 0.05)