Table 2.

Longitudinal migration

		Follow-up time
	3 months	6 months	1 year	2 years	2 year mean 95% CI
Tibial spherical tip, EGS
n	19	21	20	18
MTPM (mm)	0.46 (0.21–1.17)	0.70 (0.13–1.33)	0.88 (0.12–1.81)	0.90 (0.17–2.28)
X: posterior–anterior (mm)	0.06 (0.20)	0.08 (0.28)	0.13 (0.31)	0.16 (0.33)	–0.08 to 0.33
Y: inferior–superior (mm)	0.42 (0.27)	0.56 (0.32)	0.66 (0.36)	0.80 (0.46)	0.58 to 1.03
Z: lateral–medial (mm)	–0.02 (0.23)	–0.04 (0.32)	–0.05 (0.42)	–0.16 (0.44)	–0.38 to 0.06
Tibial component, MBRSA
n	19	21	20	18
MTPM (mm)	1.68 (0.28–2.66)	1.67 (0.60–2.71)	1.80 (0.31–3.30)	1.89 (0.41–5.49)
X: posterior–anterior (mm)	0.04 (0.62)	–0.13 (0.52)	–0.06 (0.71)	–0.18 (0.87)	–0.61 to 0.26
Y: inferior–superior (mm)	0.40 (0.27)	0.56 (0.31)	0.65 (0.38)	0.77 (0.47)	0.54 to 1.01
Z: lateral–medial (mm)	0.11 (0.22)	0.13 (0.26)	0.05 (0.23)	0.03 (0.30)	–0.12 to 0.18
Rx: valgus–varus (°)	–0.4 (1.1)	–0.2 (1.2)	–0.3 (1.3)	–0.4 (1.4)	–1.1 to 0.3
Ry: external–internal rotation (°)	–0.6 (2.6)	–0.9 (2.2)	–0.4 (2.3)	–1.8 (2.8)	–3.2 to –0.4
Rx: dorsiflexion–plantarflexion (°)	0.6 (0.8)	0.6 (1.1)	1.0 (1.2)	0.8 (1.4)	0.1 to 1.5
Talar component, MBRSA
n	16	18	17	15
MTPM (mm)	0.50 (0.12–1.26)	0.61 (0.09–2.03)	0.85 (0.17–2.85)	1.19 (0.39–1.95)
X: posterior–anterior (mm)	0.05 (0.22)	0.08 (0.40)	0.11 (0.39)	0.00 (0.18)	–0.10 to 0.10
Y: inferior–superior (mm)	–0.13 (0.14)	–0.25 (0.24)	–0.43 (0.30)	–0.41 (0.33)	–0.59 to –0.23
Z: lateral–medial (mm)	–0.01 (0.13)	–0.01 (0.16)	–0.01 (0.25)	–0.10 (0.19)	–0.21 to 0.00
Rx: valgus–varus (°)	0.1 (0.5)	0.1 (0.5)	0.5 (0.9)	0.3 (0.9)	–0.2 to 0.8
Ry: external–internal rotation (°)	–0.3 (0.9)	–0.3 (0.7)	–0.4 (1.2)	–0.0 (1.1)	–0.6 to 0.6
Rx: dorsiflexion–plantarflexion (°)	0.5 (0.7)	0.6 (1.3)	0.7 (1.3)	0.2 (1.5)	–0.6 to 1.0

The values are given as mean (SD), except for MTPM which is given as median (range)