An underlying diagnosis of osteonecrosis of bone is associated with worse outcomes than osteoarthritis after total hip arthroplasty

Table 2 Crude incidence of outcomes by primary diagnosis at total hip arthroplasty surgery

	Osteoarthritis		Osteonecrosis
	n	%	n	%
Death, 90 days	138	0.3	15	0.7
Surgical site infection, any	367	0.8	27	1.2
Deep, 1-year^a	230	0.5	13	0.6
Superficial, 30-days^b	137	0.3	14	0.6
Venous thromboembolism, 90-days	551	1.2	31	1.4
Deep vein thrombosis^c	323	0.7	18	0.8
Pulmonary embolism^d	228	0.5	13	0.6
Readmission, 90 days unplanned^e	846	5.2	64	9.6
Revision, ever^f	1,075	2.4	70	3.1

^aDeep surgical site infection excluded patient who died or left the system within 1 year without deep SSI (1549, 3.3%), n = 45974 (96.7%)
^bSuperficial surgical site infection excluded patient who died or left the system within 30 days without superficial SSI (138, 0.3%), n = 47385 (99.7%)
^cDeep vein thrombosis (DVT) excluded patient who died or left the system within 90 days without DVT (376, 0.8%), n = 47147 (99.2%)
^dPulmonary embolism (PE) excluded patient who died or left the system within 90 days without PE (374, 0.8%), n = 47149 (99.2%)
^eReadmissions includes limited sample (operative years 2009–2012 and 3 geographical regions), n = 17179. Excluded patient who died or left the system within 90 days without readmission (85, 0.5%), final n = 17094 (99.5%)
^fThe median follow-up for revision outcome was 3.2 years (inter-quartile range, 1.4–5.8 years)