Table 2.
Polynomial equations describing the relationship between independent variables and tendon stiffness or Young's modulus (YM)
| Dependent variable (Y) | Population | Independent variable (x) | Equation | R2 |
|---|---|---|---|---|
| StiffnessREL | Children | Age | Y = 18.172x − 10.514 | 0.37 |
| Mass | Y = 6.0391x − 30.084 | 0.58 | ||
| Force | Y = 0.0602x + 41.367 | 0.51 | ||
| All ages | Age | Y = −0.4852x2 + 23.681x − 22.739 | 0.70 | |
| Mass | Y = −0.0587x2 + 8.7774x − 59.307 | 0.75 | ||
| Force | Y = −7E − 06x2 + 0.0843x + 23.419 | 0.76 | ||
| StiffnessABS | Children | Age | Y = 10.165x + 45.648 | 0.15 |
| Mass | Y = 3.1554x + 40.987 | 0.21 | ||
| Force | Y = 0.0323x + 77.088 | 0.19 | ||
| All ages | Age | Y = −0.3346x2 + 16.13x + 20.275 | 0.46 | |
| Mass | Y = −0.0246x2 + 4.4102x + 25.927 | 0.48 | ||
| Force | Y = −3E − 07x2 + 0.0306x + 79.44 | 0.53 | ||
| YMREL | Children | Age | Y = 64.303x − 1.553 | 0.31 |
| Mass | Y = 16.021x + 76.986 | 0.27 | ||
| Stress | Y = 8.7919x + 146.96 | 0.32 | ||
| All ages | Age | Y = −2.6421x2 + 107.75x − 172.15 | 0.52 | |
| Mass | Y = −0.1282x2 + 20.33x + 56.477 | 0.47 | ||
| Stress | Y = −0.0492x2 + 13.857x + 41.519 | 0.51 | ||
| YMABS | Children | Age | Y = 46.032x + 127.55 | 0.17 |
| Mass | Y = 10.093 + 222.81 | 0.12 | ||
| Stress | Y = 7.68673x + 175.09 | 0.26 | ||
| All ages | Age | Y = −2.2546x2 + 86.812x − 47.289 | 0.30 | |
| Mass | Y = −0.0513x2 + 9.6423x + 270.95 | 0.23 | ||
| Stress | Y = −0.0542x2 + 12.463x + 82.278 | 0.40 |