Table 4 Function regression (dependent variable was gait speed test)

All subjects:

Knee extension

-5.013

2.555

0.051

Age

-8.306

1.695

< 0.001

Knee flexion

3.374

1.180

0.005

Sex

-80.966

34.717

0.021

Opioid medications

-2.489

1.083

0.023

Pain duration

38.014

18.334

0.040

Pain catastrophizing

-3.294

1.644

0.047

BMI

-4.283

2.393

0.075

Heat pain threshold

10.090

5.278

0.058

F value

Significance

Model fit

Overall model

9.062

< 0.001

R² = 0.345

Women:

Age

-9.749

1.802

< 0.001

Knee flexion

3.170

1.094

0.004

Opioid medications

-2.829

1.097

0.011

Pain catastrophizing

-3.538

1.847

0.058

BMI

-4.525

2.625

0.087

Women only model

10.630

< 0.001

R² = 0.312

Men:

Knee extension

-13.302

5.159

0.012

Age

-4.755

2.830

0.098

Men only model

4.358

0.017

R² = 0.129