Table 2.

Baseline characteristics of study population.

	Both centers	UMCU (n=41)	UMCG (n=127)	p-value
Age (median (IQR))	54 (40-64)	58 (47-63)	54 (38-64)	0.27
Age at onset (median (IQR))	51 (36-59)	53 (45-59)	51 (36-62)	0.26
Sex
Male	115 (68.5%)	26 (63.4%)	89 (70.1%)	0.44
Comorbidities
Diabetes mellitus	13 (7.7%)	5 (12.2%)	8 (6.3%)	0.31
Psychiatric disorder	11 (6.5)	2 (4.9%)	9 (7.1%)	0.47
Obesity	21 (12.5%)	2 (4.9%)	19 (15.0%)	0.11
Osteoporosis	5 (3.0%)	5 (12.2%)	0 (0%)	0.35
Hypothyroidism	3 (1.8%)	1 (2.4%)	2 (1.6%)	0.57
Risk factors
Smoking	63 (37.5%)	14 (34.1%)	49 (38.6%)	0.71
NSAIDs	31 (18.5%)	5 (12.2%)	26 (20.5%)	0.26
Soft drugs	6 (3.6%)	2 (4.9%)	4 (3.1%)	0.64
Hard drugs	6 (3.6%)	2 (4.9%)	4 (3.1%)	0.64
Alcohol abuse	7 (4.2%)	2 (4.9%)	5 (3.9%)	0.68
ASA classification				0.40
I	58 (35.5%)	14 (34.1%)	44 (39.3%)
II	72 (42.9%)	20 (48.8%)	52 (46.4%)
III	20 (11.9%)	4 (9.8%)	16 (14.3%)
IV	1 (0.6%)	1 (2.4%)	0 (0.0%)
Unknown	17 (10.1%)	2 (4.9%)	15 (11.8%)
BMI, n = 150 (mean (SD))	28,18 (5.38)	26.91 (4.68)	28,77 (5.54)	0.06
Unknown (n= )	18 (10.7%)	1 (2.4%)	17 (13.4%)
ISS				<0.001
<16	114 (67.9%)	16 (39.0%)	99 (78.0%)
>16	39 (23.2%)	18 (43.9%)	21 (16.5%)
Unknown	15 (8.9%)	7 (17.1%)	7 (5.5%)
Fracture location				0.002
Upper extremity	18 (10.7%)	1 (2.4%)	17 (13.4%)
Lower extremity	140 (83.3%)	33 (80.5%)	107 (84.3%)
Spine	7 (4.2%)	5 (12.2%)	2 (1.6%)
Pelvis	3 (1.8%)	2 (4.9%)	1 (0.8%)
Fracture type				0.85
Open	80 (47,6%)	18 (43.9%)	62 (48.8%)
Closed	79 (47.0%)	16 (39.0%)	63 (49.6%)
Unknown	9 (5.4%)	7 (17.1%)	2 (1.6%)
Gustilo-Anderson Classification (32)				0.04
Grade 1	16 (9.5%)	3 (7.3%)	13 (10.2%)
Grade 2	12 (7.1%)	0 (0.0%)	12 (9.4%)
Grade 3	43 (19.7%)	11 (26.8%)	22 (17.4%)
Unknown	19 (11.3%)	4 (9.8%)	15 (11.8%)