Table 1 The COF shift, Pmax, Pmean and the lateral joint pressure ratio change in response to the series of tibial varus
From: Ankle joint pressure change in varus malalignment of the tibia
0° varus | 2° varus | 4° varus | 6° varus | 8° varus | 10° varus | 12° varus | 14° varus | 16° varus | 18° varus | 20° varus | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
The COF shift (Medial) | Mean(SD)(mm) | 0(0) | 0.33(0.60) | 2.44(1.08) | 2.76(1.46) | 2.76(1.62) | 0.65(0.98) | 0.81(0.97) | 0.33(0.92) | −0.65(1.39) | − 1.46(1.46) | −1.46(1.08) |
0° varus | p value | 0.17 | 0 | 0.001 | 0.002 | – | – | – | – | – | – | |
8° varus | p value | – | – | – | – | 0.048 | 0.02 | 0.002 | 0.003 | 0 | 0.001 | |
The COF shift (Lateral) | Mean(SD)(mm) | 0(0) | 0.33(0.60) | 0.98(0.92) | 1.46(0.83) | 1.79(1.54) | 1.79(0.67) | 2.11(1.19) | 1.63(1.15) | 0.65(0.69) | 1.63(1.15) | 0.65(0.69) |
0° varus | p value | 0.17 | 0.02 | 0.002 | 0.014 | 0 | 0.002 | – | – | – | – | |
12° varus | p value | – | – | – | – | – | – | 0.285 | 0.026 | 0.197 | 0.026 | |
The Pmax (Medial) | Mean(SD)(kPa) | 5303.4(1105.1) | 4973.9(986.0) | 4883.5(841.7) | 4939.4(959.7) | 4751.8(741.5) | 4708.8(898.2) | 4710.9(959.7) | 4615.8(791.3) | 4464.1(884.4) | 4268.9(752.2) | 4432.1(948.6) |
0° varus | p value | 0.032 | 0.219 | 0.179 | 0.148 | 0.148 | 0.209 | 0.102 | 0.081 | 0.039 | 0.045 | |
The Pmax (Lateral) | Mean(SD)(kPa) | 5135.5(1095.3) | 4754.7(1205.3) | 4727.8(694.9) | 4940.1(804.1) | 5000.8(761.1) | 4844.5(756.7) | 4412.6(581.9) | 4478.0(238.0) | 4525.5(525.6) | 4324.1(866.8) | 4279.4(666.9) |
0° varus | p value | 0.022 | 0.087 | 0.362 | 0.691 | 0.439 | 0.085 | 0.096 | 0.18 | 0.13 | 0.116 | |
The Pmean (Medial) | Mean(SD)(kPa) | 2266.4(672.7) | 2107.6(654.9) | 2064.8(632.7) | 2064.4(624.5) | 2027.6(632.9) | 1891.2(563.9) | 1895.4(499.5) | 1802.2(481.1) | 1742.5(314.6) | 1587.1(453.6) | 1618.7(421.5) |
0° varus | p value | 0.021 | 0.072 | 0.056 | 0.089 | 0.007 | 0.018 | 0.004 | 0.10 | 0.007 | 0.006 | |
The Pmean (Lateral) | Mean(SD)(kPa) | 2103.8(625.1) | 2059.7(465.6) | 2109.3(510.8) | 2183.7(581.3) | 2295.3(589.7) | 2280.7(519.3) | 2043.6(456.3) | 2053.0(416.6) | 1972.1(481.0) | 1864.5(449.2) | 1748.9(467.2) |
0° varus | p value | 0.555 | 0.952 | 0.499 | 0.047 | – | – | – | – | – | – | |
8° varus | p value | – | – | – | – | 0.776 | 0.014 | 0.015 | 0.012 | 0.01 | 0.002 | |
The lateral joint pressure ratio | Mean(SD) | 0.481(0.12) | 0.499(0.11) | 0.508(0.11) | 0.515(0.11) | 0.531(0.11) | 0.548(0.11) | 0.519(0.10) | 0.534(0.10) | 0.527(0.09) | 0.540(0.10) | 0.517(0.10) |
0° varus | p value | 0.11 | 0.122 | 0.088 | 0.011 | 0.002 | – | – | – | – | – | |
10° varus | p value | – | – | – | – | – | 0.014 | 0.191 | 0.096 | 0.405 | 0.002 | |