Table 3 Comparison between cases without cervical surgery and those with cervical surgery

Case, no

174

28

Sex, female/male, o

83/91

13/15

Decompression/posterior fusion, no

67/107

23/5

One-stage/two-stage additional operation

–

11/17

Period between cervical and lumbar surgery, average, years

–

1.0 ± 1.3 (0–5)

Age, average (range)

72.2 ± 8.5 (32–89)

70.8 ± 10.6 (43–92)

NS

YAM, average (range)

92.4 ± 17.8 (48–137)

93.8 ± 17.4 (69–127)

NS

Operative time, average (range), min

221.4 ± 108.5 (44–749)

201.6 ± 107.4 (70–572)

NS

Blood loss, average (range), mL

381.5 ± 493.1 (6–4150)

315.5 ± 366.5 (70–1450)

NS

Pre lumbar operative L-JOA score, average (range), points

14.3 ± 4.5 (− 2–24)

13.2 ± 5.4 (− 2–22)

NS

Pre cervical operative L-JOA score, average (range), points

–

14.8 ± 7.3 (3–26)

Postoperative L-JOA score, average (range), points

23.5 ± 4.3 (9–29)*

19.9 ± 5.0 (11–29)

0.0005

Recovery rate of L-JOA score, average (range), %

62.8 ± 25.8 (− 8.3–100)*

39.8 ± 35.5 (− 57.1–100)

0.0003

Preoperative C-JOA score, average (range), points

–

10.3 ± 2.8 (5–15)

Postoperative C-JOA score, average (range), points

–

12.1 ± 3.0 (6.5–17)

Recovery rate of C-JOA score, average (range), %

–

28.5 ± 31.3 (0–100)

Symptomatic cervical stenosis, no

30 (17.2%)

28 (100%)

Revisions, no

24 (13.8%)

0 (0%)

C-OPLL, no

17 (9.8%)

6 (21.4%)

NS

HT, no

97 (55.7%)

15 (53.6%)

NS

HL, no

26 (14.9%)

8 (28.6%)

NS

DM, no

40 (23.0%)

8 (29.3%)

NS

Smoking, no

57 (32.8%)

6 (21.4%)

NS

IHD, no

31 (17.8%)

4 (14.3%)

NS

HD, no

12 (6.9%)

4 (14.3%)

NS

Collagen disease, no

15 (8.6%)

1 (3.6%)

NS

Obesity, BMI > 25, no

71 (40.8%)

12 (42.9%)

NS

Artificial joint, TKA or THA, no

10 (5.7%)

1 (3.6%)

NS

Osteoporosis, YAM < 70%, no

23 (13.2%)

0 (0%)