Table 1 Baseline patient characteristics according to the presence of obesity before and after case-control matching
Characteristic | Before matching | After matching | ||||
|---|---|---|---|---|---|---|
Non-obese (n = 181) | Obese (n = 30) | p-value | Non-obese (n = 86) | Obese (n = 29) | p-value | |
Age (years) | 53.5 ± 15.0 | 43.3 ± 16.5 | < 0.001 | 46.6 ± 15.5 | 44.1 ± 16.2 | 0.45 |
Male/Female (%) | 98/83 (54.1/45.9) | 15/15 (50.0/50.0) | 0.67 | 41/45 (47.7/52.3) | 14/15 (48.3/51.7) | 0.96 |
BMI (kg/m2) | 24.2 ± 2.7 | 33.0 ± 3.2 | < 0.001 | 24.3 ± 2.7 | 33.0 ± 3.3 | < 0.001 |
CCI score | 0.37 ± 0.74 | 0.57 ± 1.45 | 0.26 | 0.29 ± 0.68 | 0.59 ± 1.48 | 0.15 |
ASA score (%) | 0.58 | 0.51 | ||||
1 | 47 (26.1) | 6 (20.0) | 27 (31.4) | 6 (20.7) | ||
2 | 105 (58.3) | 22 (73.3) | 50 (58.1) | 21 (72.4) | ||
3 | 25 (13.9) | 2 (6.7) | 7 (8.1) | 2 (6.9) | ||
4 | 1 (0.6) | 0 (0.0) | 0 (0.0) | 0 (0.0) | ||
5 | 2 (1.1) | 0 (0.0%) | 2 (2.3) | 0 (0.0) | ||
Smoking status | 0.53 | 0.68 | ||||
Non-smoker | 134 (74.0) | 20 (66.7) | 63 (73.3) | 19 (65.5) | ||
Ex-smoker | 18 (9.9) | 5 (16.7) | 10 (11.6) | 5 (17.2) | ||
Current smoker | 29 (16.0) | 5 (16.7) | 13 (15.1) | 5 (17.2) | ||
VAS for back pain | 4.91 ± 2.76 | 5.06 ± 2.66 | 0.83 | 5.06 ± 2.88 | 5.06 ± 2.66 | > 0.99 |
VAS for leg pain | 6.87 ± 2.40 | 6.71 ± 2.42 | 0.80 | 7.04 ± 2.33 | 6.71 ± 2.42 | 0.61 |
ODI | 53.2 ± 21.2 | 50.5 ± 13.2 | 0.62 | 54.9 ± 21.0 | 50.5 ± 13.2 | 0.43 |
EQ-5D | 0.438 ± 0.200 | 0.340 ± 0.150 | 0.21 | 0.439 ± 0.200 | 0.340 ± 0.150 | 0.22 |
HIVD type | 0.62 | 0.72 | ||||
Protrusion | 7 (3.9) | 0 (0.0) | 3 (3.5) | 0 (0.0) | ||
Extrusion | 123 (68.0) | 23 (76.7) | 60 (69.8) | 22 (75.9) | ||
Sequestration | 5 (2.8) | 1 (3.3) | 2 (2.3) | 1 (3.4) | ||
Migration | 46 (25.4) | 6 (20.0) | 21 (24.4) | 6 (20.7) | ||
HIVD containment | 93 (51.4) | 11 (36.7) | 0.14 | 44 (51.2) | 10 (34.5) | 0.12 |
HIVD canal compromise | 0.09 | 0.29 | ||||
Mild (less than 1/3) | 76 (42.0) | 7 (23.3) | 28 (32.6) | 7 (24.1) | ||
Moderate | 57 (31.5) | 10 (33.3) | 33 (38.4) | 9 (31.0) | ||
Severe (over 2/3) | 48 (26.5) | 13 (43.3) | 25 (29.1) | 13 (44.8) | ||
HIVD zone | 0.35 | 0.51 | ||||
Central | 28 (15.5) | 7 (23.3) | 19 (22.1) | 7 (24.1) | ||
Paracentral | 130 (71.8) | 19 (63.3) | 58 (67.4) | 18 (62.1) | ||
Foraminal | 15 (8.3) | 4 (13.3) | 6 (7.0) | 4 (13.8) | ||
Extraforaminal | 8 (4.4) | 0 (0.0) | 3 (3.5) | 0 (0.0) | ||
HIVD location | 0.19 | 0.19 | ||||
Disc level | 96 (53.0) | 22 (73.3) | 43 (50.0) | 21 (72.4) | ||
Infrapedicle level | 24 (13.3) | 3 (10.0) | 13 (15.1) | 3 (10.3) | ||
Pedicle level | 27 (14.9) | 3 (10.0) | 14 (16.3) | 3 (10.3) | ||
Suprapedicle level | 34 (18.8) | 2 (6.7) | 16 (18.6) | 2 (6.9) | ||
HIVD calcification | 22 (12.2) | 5 (16.7) | 0.49 | 6 (7.0) | 5 (17.2) | 0.10 |
HIVD side | 0.80 | 0.55 | ||||
Right | 89 (49.2) | 14 (46.7) | 36 (41.9) | 14 (48.3) | ||
Left | 92 (50.8) | 16 (53.3) | 50 (58.1) | 15 (51.7) | ||
Operation level | 0.81 | 0.87 | ||||
L2–3 | 5 (2.8) | 1 (3.3) | 1 (1.2) | 1 (3.4) | ||
L3–4 | 23 (12.7) | 2 (6.7) | 5 (5.8) | 2 (6.9) | ||
L4–5 | 99 (54.7) | 18 (60.0) | 52 (60.5) | 17 (58.6) | ||
L5–S1 | 54 (29.8) | 9 (30.0) | 28 (32.6) | 9 (31.0) | ||