Low Body Mass Index and Blood Loss in Primary Total Hip Arthroplasty: Results from 236 Consecutive Ankylosing Spondylitis Patients

Table 2

Preoperative baseline characteristics of 236 AS patients.

	Underweight group	Normal weight group	𝑃
Disease duration (y)*	13 (4)	12 (6)	0.100
BASDAI*	5.2 (0.8)	5.3 (0.8)	0.334
BASFI	5.5 (0.7)	5.0 (0.8)	<0.001
BASRI-hip 4/3	56/35	87/58	0.841^†
Osteoporosis/nonosteoporosis	15/91	10/145	0.020^†
TT (S)*	13.1 (0.6)	13.1 (0.8)	0.876
APTT (S)*	36.8 (2.9)	36.9 (3.3)	0.808
Hb-pre (g/L)*	127 (16)	128 (15)	0.227
HCT-pre (%)*	38 (4)	39 (4)	0.090
PLT (×10^9/L)*	252 (62)	248 (59)	0.527
ALB (g/L)*	37 (4)	37 (3)	0.073

∗Mean (SD). ^†Chi-square test.
BASDAI: Bath Ankylosing Spondylitis Disease Activity Index; BASFI: Bath Ankylosing Spondylitis Functional Index; BASRI-hip: Bath Ankylosing Spondylitis Radiology Hip Index; TT: thromboplastin time; APTT: activated partial thromboplastin time; Hb-pre: preoperative hemoglobin; HCT: hematocrit; PLT: platelet; ALB: albumin.