Table 2 Mediation by osteophytes on the associations between total cartilage defects and changes in knee symptoms

 Indirect effect

0.84 (− 0.94, 2.81)

0.36

1.74 (0.15, 3.44)

0.03

1.95 (0.70, 3.32)

< 0.01

 Direct effect

2.68 (− 0.80, 6.27)

0.13

1.78 (− 1.40, 4.93)

0.28

1.58 (− 1.45, 4.76)

0.30

 Total effect

3.53 (0.53, 6.66)

0.02

3.53 (0.52, 6.34)

0.02

3.53 (0.60, 6.55)

0.02

 Proportion mediated %

NA

49%

55%

 Indirect effect

0.62 (− 0.60, 1.91)

0.29

1.26 (0.24, 2.36)

0.02

1.24 (0.45, 2.16)

< 0.01

 Direct effect

1.43 (− 0.72, 3.53)

0.19

0.79 (− 1.38, 2.98)

0.49

0.81 (− 1.11, 2.71)

0.41

 Total effect

2.05 (0.08, 4.06)

0.04

2.05 (0.14, 4.12)

0.04

2.05 (0.09, 3.99)

0.04

 Proportion mediated %

NA

62%

61%

 Indirect effect

0.22 (− 0.56, 1.04)

0.56

0.48 (− 0.28, 1.26)

0.22

0.70 (0.12, 1.35)

0.01

 Direct effect

1.29 (− 0.23, 2.84)

0.10

1.03 (− 0.50, 2.52)

0.15

0.81 (− 0.41, 2.06)

0.21

 Total effect

1.51 (0.26, 2.89)

0.02

1.51 (0.23, 2.81)

0.02

1.51 (0.36, 2.74)

0.01

 Proportion mediated %

NA

NA

46%

 Indirect effect

0.35 (− 0.40, 1.11)

0.36

1.17 (0.35, 2.09)

< 0.01

0.81 (0.26, 1.51)

< 0.01

 Direct effect

0.17 (− 1.35, 1.75)

0.82

− 0.65 (− 2.25, 0.80)

0.39

− 0.30 (− 1.80, 1.11)

0.67

 Total effect

0.52 (− 0.86, 1.93)

0.45

0.52 (− 0.80, 1.88)

0.46

0.52 (− 0.90, 1.91)

0.50

 Proportion mediated %

NA

NA

NA

 Indirect effect

4.22 (− 0.90, 9.55)

0.10

6.63 (1.17, 11.90)

0.02

5.19 (1.46, 9.91)

< 0.01

 Direct effect

2.74 (− 6.08, 11.64)

0.56

0.33 (− 8.07, 9.99)

0.92

1.77 (− 6.74, 10.03)

0.69

 Total effect

6.96 (− 1.78, 15.72)

0.11

6.96 (− 0.72, 16.12)

0.09

6.96 (− 1.22, 15.71)

0.10

 Proportion mediated %

NA

NA

NA