Table 3 Pre and post-operative data in group 1 and 2 and the changes between the groups

Knee flexion contracture (degrees)

4.6 (5.3)

2.1 (8.3)

2.5 (7.4)

0.071

17.2 (4.9)

9.6 (9.3)

8.2 (8.8)

0.001*

5.7 (1.5–9.9)

0.009*

Gait Deviation Index

66 (19)

74 (15)

8 (13)

0.004*

60 (13)

69 (15)

9 (12)

0.001*

1 (5–8)

0.675

Knee flexion at initial contact (degrees)

47.6 (13.4)

range 30–91

39.1 (12.1)

range 12–69

8.5 (13.4)

0.002*

52.2 (9.4)

range 30–72

42.4 (10.4)

range 32–75

9.8 (13.0)

0.001*

1.3 (−5.6–8.1)

0.716

Minimal knee flexion in stance (degrees)

21.4 (16.1)

range 21–75

12.1 (16.0)

range 12–61

9.3 (14.7)

0.002*

32.2 (14.2)

range 18–69

17.0 (15.9)

range

8–74

15.2 (16.3)

0.001*

5,9 (− 2.1–13.9)

0.148

Walking speed (cm/s)

79 (27)

78 (30)

−0.3 (22,8)

0.786

55 (30)

67 (35)

11.5 (25.1)

0.018*

−11,8 (0.6–24.2)

0.062

Step length (cm)

40.8 (10.0)

43.9 (10.0)

3.1 (6.4)

0.017*

33.9 (13.2)

39.3 (14.9)

5.4 (10.5)

0.008*

−2.3 (−2.3–7.0)

0.316

GMFM-D (points)

23.3 (8.0)

24.2 (9.5)

−1.9 (8.2)

0.553

16.5 (10.1)

22.1 (9.3)

3.1 (6.7)

0.001*

−5.0 (1.1–8.8)

0.014*

Popliteal angle (degrees)

59.0 (12.4)

49.1 (17.0)

9.9 (15.1)

0.001*

71.9 (12.2)

55.7 (13.0)

16.2 (18.5)

< 0.05*

6.2 (−2.6–15.1)

0.163

Hamstring spasticity (points)

1.3 (0.8)

0.9 (0.5)

0.4 (0.8)

0.013*

1.6 (0.7)

0.9 (0.5)

0.7 (0.8)

< 0.05*

0.2 (−0.2–0.6)

0.358