Table 1 Baseline data of included patients
Characteristics | UPSF group | BPSF group | X2/t | p |
|---|---|---|---|---|
Age (year), mean ± SD | 63.29 ± 6.97 | 64.10 ± 6.69 | 0.444 | 0.659 |
Gender (n, %) | 27 | 30 | 0.198 | 0.656 |
 Male | 5(18.5%) | 7(23.3%) |  |  |
 Female | 22(81.5%) | 23(76.7%) |  |  |
BMI (kg/m2), mean ± SD | 25.93 ± 2.97 | 25.87 ± 2.70 | 0.073 | 0.942 |
ASA (n, %) | Â | Â | 1.721 | 0.613 |
 Grade 1 | 26(96.3%) | 26(86.7%) |  |  |
 Grade 2 | 1(3.7%) | 3(10%) |  |  |
 Grade 3 | 0 | 1(1.8%) |  |  |
Operative site(n, %) | Â | Â | 1.417 | 0.234 |
 L3/4 | 21(77.8%) | 19(63.3%) |  |  |
 L4/5 | 6(22.2%) | 11(36.7%) |  |  |
Follow-up time (months) | 29.15 ± 3.91 | 27.87 ± 3.00 | 1.396 | 0.168 |