Table 1 Demographic data for the three groups

Age (years)

69 ± 8.9

70.4 ± 7.3

70.4 ± 8.2

0.412

1

0.296

Sex (male:female)

59:26

60:54

8:63

BMI

24 ± 3.8

23.9 ± 3.7

22.8 ± 4.1

1

0.024*

0.026*

CE (degrees)

26.9 ± 7.9

27.9 ± 7.6

26.5 ± 8.1

0.56

0.3

1

Sharp (degrees)

41.2 ± 4

41 ± 4.1

42.3 ± 5.2

1

0.022*

0.141

Limb length discrepancy (mm)

3.2 ± 3.4

3.1 ± 2.6

3.3 ± 2.5

1

1

1

Sacral fusion

0 / 167

18 / 225

112/138

Number of fusion levels

0

1.4 ± 0.6

10 ± 3.0

 < 0.001*

 < 0.001*

 < 0.001*

Follow up period (months)

35.8 ± 11.9

43.5 ± 15.4

48.9 ± 22.3

 < 0.001*

0.008*

 < 0.001*