Table 4.  Comparison of intraclass correlation coefficients for back extensor musculature between groups.

%HAT

 

Left
ULES

Right ULES

Left
LLES

Right LLES

Left
BF

Right BF

Mean

p

100

Control

.80

.88

.94

.93

.94

.91

.90

.037*

 

LBP

.74

.88

.85

.81

.72

.88

.81

 

110

Control

.81

.74

.92

.90

.95

.93

.88

.044*

 

LBP

.60

.79

.75

.72

.83

.86

.76

 

120

Control

.88

.93

.97

.95

.98

.96

.95

.005*

 

LBP

.57

.80

.73

.74

.88

.88

.77

 

130

Control

.85

.91

.96

.94

.98

.93

.93

.008*

 

LBP

.37

.71

.63

.68

.86

.84

.68

 

140

Control

.89

.92

.96

.94

.98

.95

.94

.006*

 

LBP

.46

.72

.57

.64

.89

.88

.69

 

150

Control

.89

.92

.97

.94

.98

.97

.95

.011*

 

LBP

.03

.61

.33

.44

.88

.86

.53

 

160

Control

.87

.90

.90

.87

.98

.80

.89

.019*

 

LBP

.21

.67

.67

.62

.66

.90

.62

 

170

Control

.84

.90

.95

.91

.98

.95

.92

.025*

 

LBP

.45

.31

.67

.65

.92

.92

.65

 

MVIA

Control

.92

.96

.96

.93

.99

.96

.95

.021*

 

LBP

.36

.52

.72

.72

.93

.94

.70

 

p

 

< .0001†

.002†

< .0001†

< .0001†

.001†

.043†

   
HAT: head, arms, trunk segment. LBP: Low back pain. ULES: Upper lumbar erector spinae. LLES: Lower lumbar erector spinae. BF: biceps femoris  * p ≤ 0.05 between LBP and Controls Groups for each % HAT. † p ≤ 0.05 between LBP and Controls Groups for the specific muscle group in that column