Table 2 Range of motion and Harris Hip Scores for all recruited patients preoperatively and postoperatively of both two groups

Flexion (°)

88 ± 25

113 ± 7

91 ± 16

116 ± 5

t = − 5.86, p < .001*

t = − 9.97, p < .001*

T = − 0.55, p = .59

T = − 1.37, p = .18

Extension (°)

− 1 ± 3

0 ± 0

− 2 ± 3

0 ± 0

t = − 1.75, p = .095

t = − 2.30, p = .031*

T = 0.26, p = .54

–

Abduction (°)

20 ± 11

38 ± 4

23 ± 6

36 ± 3

t = − 10.29, p < .001*

t = − 12.88, p < .001*

T = − 1.08, p = .29

T = 1.58, p = .12

HHS

38 ± 6

87 ± 6

40 ± 4

89 ± 6

t = − 65.35, p < .001*

t = − 77.36, p < .001*

T = − 1.24, p = .22

T = − 1.36, p = .18