Table 1 Comparison of clinical characteristics, surgical factors, and radiographic parameters of the Subsidence and Non-subsidence groups

No. of patients

39

63

Clinical characteristics

Age (years)

62.10 ± 9.60

58.09 ± 8.82

Sex (male/female)

17/22

32/31

BMI (kg/m²)

25.11 ± 2.97

25.03 ± 3.07

Age-adjusted CCI

2.15 ± 1.29

1.67 ± 1.34

Hypertension (Yes/No)

11/28

21/42

Smoking history (Yes/No)

2/37

9/54

Drinking history (Yes/No)

4/35

11/52

Glucocorticoid use > 6 months

2/37

7/56

Diagnosis

 Lumbar spondylolisthesis

22

43

 Lumbar instability

16

15

 Disk herniation

1

5

Antiosteoporotic drug treatment (Yes/No)

10/29

6/57

Follow-up time (months)

20.03 ± 4.12

20.10 ± 4.31

Surgical factors

Level

 L2–3

2

2

 L3–4

8

17

 L4–5

29

34

Cage height (mm)

10.77 ± 1.27

10.73 ± 1.61

Cage length (mm)

48.85 ± 2.68

49.29 ± 3.46

Cage position

22.72 ± 7.69

24.56 ± 6.76

Radiographic parameters

Preop disk height in %

44.26 ± 11.83

48.01 ± 11.66

Immediate postop disk height in %

64.04 ± 9.66

64.09 ± 9.95

Change in disk height (mm)

3.51 ± 1.14

2.99 ± 1.05

Superior endplate morphology (Flat/Concave)

2/37

16/47

Inferior endplate morphology (Flat/Concave)

1/38

14/49

Fusion at final follow-up (Yes/No)

8/31

11/52

Cage subsidence at follow-up(mm)

3.59 ± 1.22

1.13 ± 0.56

VBQ score

3.83 ± 0.82

2.98 ± 0.39

Average lumbar DEXA T-score

 − 1.76 ± 0.98

 − 1.02 ± 1.08