Table 4 Association of rod fracture risk with postoperative characteristics

Postoperative sagittal imbalance

≥50 mm

3

22

1.5 (0.3; 8.1)

>0.5

<50 mm

3

33

Postoperative coronal imbalance

≥30 mm

2

16

1.2 (0.2; 7.1)

>0.5

<30 mm

4

38

Postoperative lumbar lordosis (LL)

<49°

4

21

2.5 (0.5; 12.4)

0.3

≥49°

3

40

Postoperative thoracic kyphosis

≥40°

3

33

0.5 (0.1; 2.6)

0.5

<40°

4

23

Postoperative pelvic incidence (PI)

<42°

2

11

1.8 (0.3; 11.0)

>0.5

≥42°

4

39

Postoperative PI-LL

>10°

1

16

0.4 (0.04; 3.3)

0.4

≤10°

5

28

Postoperative pelvic tilt

≤20

4

27

1.9 (0.3; 11.4)

0.5

>20

2

26

Postoperative coronal Cobb angle

<25°

7

54

N/A

0.4

≥25°

0

14

Pseudarthrosis at ≥1 year follow-up

Yes

4

3

28.9 (4.4; 191.7)

<0.001

No

3

65