Is vertebral bone quality an independent predictor of total blood loss in transforaminal lumbar interbody fusion?

Table 1 Demographic information of all patients, mean ± SD

	Total	1 level	2 levels	≥ 3 levels	P value
n	247	172	60	15
Male/female	93/154	70/102	17/43	6/9	0.231
Age (year)	59.59 ± 9.09	59.58 ± 9.45	60.03 ± 8.75	57.93 ± 5.82	0.727
Hospital stays (day)	14.23 ± 3.81	14.07 ± 3.07	14.23 ± 4.45	16.13 ± 4.53	0.133
BMI (kg/m2)	25.85 ± 3.31	25.57 ± 3.14	26.61 ± 3.76	27.57 ± 2.86	0.049
Fixation segments	1.37 ± 0.62	1	2	3.13 ± 0.35
Hb (preoperative, g/L)	135.64 ± 14.93	136.39 ± 15.81	133.85 ± 11.91	134.13 ± 15.57	0.486
HCT (preoperative, %)	40.18 ± 3.85	40.34 ± 4.08	39.72 ± 3.08	40.10 ± 3.96	0.556
ESR (mm/hour)	14.27 ± 11.87	14.03 ± 10.69	15.02 ± 15.24	14.00 ± 9.79	0.855
PT (second)	11.34 ± 0.84	11.45 ± 0.89	11.12 ± 0.65	11.09 ± 0.69	0.014
APTT (second)	27.51 ± 4.30	26.99 ± 4.19	28.80 ± 4.17	28.29 ± 5.04	0.014
INR	0.98 ± 0.08	0.98 ± 0.08	0.97 ± 0.07	0.95 ± 0.53	0.352
TT (second)	16.84 ± 2.30	17.12 ± 2.29	16.19 ± 2.16	16.34 ± 2.42	0.017
FIB (g/L)	2.81 ± 0.70	2.78 ± 0.67	2.85 ± 0.77	3.01 ± 0.68	0.422
D-dimer (mg/L)	0.49 ± 0.83	0.53 ± 0.94	0.37 ± 0.33	0.58 ± 0.79	0.405
PLT (109/L)	235.16 ± 59.11	232.73 ± 57.07	243.65 ± 67.26	229.00 ± 45.98	0.431
TBL (mL)	796.95 ± 569.94	761.26 ± 640.40	827.04 ± 323.71	1085.84 ± 384.73	0.095
VBQ (L1-4 median)	3.50 ± 0.70	3.58 ± 0.72	3.39 ± 0.67	3.15 ± 0.44	0.025
VBQ (L1-4 average)	3.49 ± 0.67	3.55 ± 0.69	3.40 ± 0.66	3.14 ± 0.41	0.039
VBQ (S1)	3.19 ± 0.72	3.21 ± 0.73	3.21 ± 0.71	2.87 ± 0.49	0.197
VBQ (fixation levels)	3.42 ± 0.71	3.46 ± 0.73	3.37 ± 0.69	3.08 ± 0.41	0.120

BMI: Body mass index; Hb: Hemoglobin; HCT: Hematocrit; ESR: Erythrocyte sedimentation rate; PT: Prothrombin time; APTT: Activated partial thromboplastin time; INR: International normalized ratio; TT: Thrombin time; FIB: Fibrinogen; PLT: Platelet count; TBL: Total blood loss; VBQ: Vertebral bone quality.