Table 3 Comparison of the screw pull-out group and the normal group
Variable | Non-pull-out group | Pull-out group | P-value |
|---|---|---|---|
Patients | 50 (65.8%) | 26 (34.2%) | |
Age, years | 65.2 ±13.7 | 76.9 ± 12.5 | P = 0.0001* |
Sex | |||
Male | 33 | 14 | |
Female | 17 | 12 | P = 0.33 |
Body mass index | 22.1 ± 3.7 | 21.8 ± 2.8 | P = 0.80 |
Operating time, min | 161.3 ± 76.8 | 199.3 ± 97.4 | P = 0.10 |
Estimated blood loss, g | 229.1 ± 269.4 | 217.9 ± 197.1 | P = 0.87 |
Disease | |||
Injury | 35 | 20 | P = 0.60 |
Metastasis | 11 | 4 | P = 0.56 |
Spondylitis | 4 | 2 | P = 1.00 |
Fused segments, n | 4.6 ± 1.3 | 5.3 ± 1.0 | P = 0.0031* |
Surgical procedure | |||
PPS | 38 | 19 | |
Open | 12 | 7 | P = 0.79 |
Use of a hook system | 2 | 4 | P = 0.17 |
Preoperative complications | |||
DISH | 12 | 16 | P = 0.0023* |
Osteoporosis | 15 | 17 | P = 0.0038* |
Rheumatoid arthritis | 1 | 1 | P = 1.00 |
Diabetes | 9 | 7 | P = 0.39 |
Asthma | 6 | 0 | P = 1.00 |
Requirement for dialysis | 2 | 1 | P = 1.00 |
Smoking | 11 | 1 | P = 1.00 |
Type of rods | |||
Titanium | 39 | 21 | |
Cobalt chrome | 11 | 5 | P = 1.00 |
Screw designs | |||
Mixed thread | 11 | 4 | |
Dual thread | 39 | 22 | P = 1.00 |
Degree of sagittal alignment between the UIV and LIV (kyphotic angle) | |||
Intraoperative CBCT, deg | 6.5 ± 24.3 | 5.3 ± 22.3 | P = 0.81 |
Postoperative CT, deg | 5.9 ± 24.3 | 5.7 ± 22.5 | P = 0.97 |
Alignment change in the sagittal plane from CBCT to CT, deg | 2.2 ± 1.6 | 1.9 ± 1.3 | P = 0.55 |
Screw density, screws/level | 1.69 ± 0.24 | 1.70 ± 0.21 | P = 0.41 |