Table 4 Spinal motion reliability and measurement error in the frontal and horizontal planes for LBP patients divided into subgroups

Number of subjects

89

130

146

73

161

58

87

132

148

71

Frontal plane:

ROM lateral flexion

ICC(1,1)

0.75

0.63

0.55

0.81

0.68

0.67

0.65

0.69

0.64

0.74

95 % CI

[0.66-0.84]

[0.53-0.73]

[0.44-0.67]

[0.74-0.89]

[0.60-0.77]

[0.53-0.81]

[0.52-0.77]

[0.6-0.78]

[0.55-0.74]

[0.64-0.85]

LOA_LL(degree)

−14

−16.2

−17

−11.9

−14.1

−18.8

−15

−15.8

−16.4

−13.3

LOA_UL(degree)

12.2

17.1

16.6

12

14.5

16.9

14.4

15.8

15.9

13.7

Mean velocity lateral flexion

ICC(1,1)

0.7

0.71

0.69

0.73

0.75

0.58

0.74

0.68

0.68

0.76

95 % CI

[0.59-0.8]

[0.63-0.8]

[0.61-0.78]

[0.62-0.84]

[0.68-0.81]

[0.4-0.75]

[0.65-0.84]

[0.58-0.77]

[0.59-0.76]

[0.66-0.86]

LOA_LL(ratio)

−10.1

−9.3

−10.1

−8.9

−9.4

−10.3

−9

−10.1

−9.7

−9.6

LOA_UL(ratio)

7.6

8.9

9.1

7

7.8

10.1

7.8

8.8

8.7

7.8

Phase-plot Area lateral flexion

ICC(1,1)

0.74

0.67

0.67

0.75

0.72

0.65

0.72

0.68

0.68

0.73

95 % CI

[0.65-0.84]

[0.58-0.77]

[0.58-0.76]

[0.65-0.85]

[0.65-0.8]

[0.5-0.8]

[0.62-0.82]

[0.59-0.77]

[0.6-0.77]

[0.63-0.84]

LOA_LL(ratio)

−2265

−2381

−2472

−2127

−2253

−2679

−1982

−2598

−2358

−2398

LOA_UL(ratio)

1538

2460

2253

1641

1943

2375

1706

2269

2112

1961

Jerk index lateral flexion

ICC(1,1)

0.73

0.73

0.75

0.69

0.74

0.69

0.80

0.60

0.76

0.61

95 % CI

[0.63-0.82]

[0.64-0.81]

[0.67-0.81]

[0.57-0.81]

[0.67-0.81]

[0.56-0.83]

[0.73-0.88]

[0.5-0.71]

[0.69-0.83]

[0.47-0.76]

LOA_LL(ratio)

−6.5

−7.35

−7.28

−6.56

−6.19

−9.08

−7.27

−6.95

−7.39

−6.24

LOA_UL(ratio)

8.83

7.47

7.78

8.64

7.96

8.03

8.39

7.91

7.71

8.72

Horizontal plane:

ROM rotation

ICC(1,1)

0.69

0.28

0.36

0.56

0.44

0.41

0.45

0.43

0.35

0.63

95 % CI

[0.57-0.8]

[0.12-0.44]

[0.21-0.5]

[0.4-0.72]

[0.32-0.57]

[0.19-0.62]

[0.28-0.61]

[0.3-0.57]

[0.21-0.49]

[0.49-0.77]

LOA_LL(degree)

−18.8

−29

−26.6

−22.8

−24.9

−26.3

−26.5

−24.6

−27.8

−19.3

LOA_UL(degree)

14.2

23.3

20.8

18.6

20.9

17.6

20.7

19.7

21.7

15.9

Mean velocity rotation

ICC(1,1)

0.56

0.51

0.51

0.57

0.53

0.52

0.54

0.52

0.5

0.59

95 % CI

[0.42-0.71]

[0.38-0.63]

[0.39-0.63]

[0.41-0.72]

[0.42-0.64]

[0.33-0.71]

[0.4-0.69]

[0.39-0.64]

[0.37-0.62]

[0.44-0.74]

LOA_LL(ratio)

−10.8

−12.4

−12.6

−10

−11.7

−12.3

−11.8

−11.9

−12

−11.3

LOA_UL(ratio)

7.4

9.6

9.3

7.5

8.8

8.8

9.1

8.6

8.6

9.2

Phase-plot Area rotation

ICC(1,1)

0.68

0.4

0.45

0.6

0.47

0.57

0.50

0.5

0.45

0.6

95 % CI

[0.57-0.79]

[0.26-0.55]

[0.32-0.58]

[0.45-0.75]

[0.35-0.59]

[0.39-0.74]

[0.34-0.66]

[0.37-0.63]

[0.32-0.58]

[0.44-0.75]

LOA_LL(ratio)

−1847

−2789

−2673

−1970

−2460

−2434

−2289

−2566

−2524

−2311

LOA_UL(ratio)

1254

2253

2014

1612

1989

1629

1760

1987

1863

1963

Jerk index rotation

ICC(1,1)

0.58

0.58

0.65

0.37

0.59

0.53

0.66

0.44

0.6

0.49

95 % CI

[0.44-0.72]

[0.46-0.69]

[0.55-0.74]

[0.17-0.57]

[0.49-0.69]

[0.35-0.72]

[0.54-0.78]

[0.31-0.58]

[0.5-0.7]

[0.31-0.67]

LOA_LL(ratio)

−7.8

−7.96

−7.99

−7.73

−7.92

−7.97

−9.09

−7.1

−8.33

−7.1

LOA_UL(ratio)

9.7

8.14

8.28

9.75

9.01

8.24

8.95

8.63

8.98

8.41