Table 4.
FH patient xanthoma subgroup analysis of Achilles tendon MRI characteristics and biomechanical outcomes
| Outcome | Xanthoma | No-xanthoma | p-value | Statistic | Effect size |
|---|---|---|---|---|---|
| Participants (female/male) | 8 (4/4) | 25 (12/13) | |||
| CSA (mm2) | 117 ± 29 [93–141] | 75.7 ± 20 [68–84] | 0.004 | t=-3.767 | 1.85 |
| Tendon thickness (mm) | 8.4 ± 1.8 [6.9–9.9] | 6.7 ± 1.7 [5.9–7.4] | 0.034 | t=-2.434 | 0.99 |
| Total lipid content (AU) | 5.4 ± 2.7 [3.1–7.7] | 3.2 ± 1.0 [2.8–3.7] | 0.062 | t=-2.184 | 1.08 |
| Total water content (AU) | 7.4 ± 2.6 [5.2–9.5] | 4.7 ± 1.8 [3.9–5.4] | 0.02 | t=-2.8 | 1.21 |
| Stiffness (N/mm) | 344 ± 93 [266–423] | 384 ± 91 [346–422] | 0.314 | t = 1.053 | 0.44 |
| Young’s mod. (MPa) | 657 ± 258 [442–873] | 1128 ± 340 [988–1270] | 0.001 | t = 4.145 | 1.46 |
| Peak strain (%) | 7.9 ± 1.9 [6.3–9.5] | 6.0 ± 1.7 [5.3–6.7] | 0.029 | t=-2.606 | 1.09 |
| Peak tendon force (N) | 3880 ± 550 [3421–4340] | 3456 ± 693 [3170–3742] | 0.096 | t=-1.778 | 0.64 |
| Peak stress (N/mm2) | 39.4 ± 8.5 [32.3–46.7] | 52.5 ± 14 [46.7–58.3] | 0.005 | t = 2.462 | 1.01 |
| RFD (N/sec) | 1600 ± 613 [1088–2113] | 1330 ± 599 [1083–1577] | 0.297 | t=-1.092 | 0.62 |
Group descriptives displayed as mean ± SD [95% CI]. p-values and test statistic obtained through Welch’s t-tests. Effect size calculated as Cohen’s d. CSA = cross-sectional area; AU = arbitrary units; RFD = rate of force development