Increasing but levelling out risk of revision due to infection after total hip arthroplasty: a study on 108,854 primary THAs in the Norwegian Arthroplasty Register from 2005 to 2019

Figures & data

Figure 1. Relationship between year of primary surgery and risk of revision due to deep infection (with 95% confidence interval) for all THAs, adjusted for sex, age, ASA class, indication for primary THA, duration of surgery, surgical approach, and modularity of the THA. The broken line represents the HRR in 2005 (HRR = 1).

Figure 2. Curves of adjusted revision-percentage due to deep infection, for all THAs, for cemented THAs, uncemented THAs, reverse hybrid THAs, and hybrid THAs, for 3 periods of primary surgery, adjusted for sex, age, ASA class, indication for primary THA, duration of surgery, surgical approach, and modularity of the THA.

Table 1. Absolute annual number of primary THAs and revisions due to infection for the period 2005–2019

Year of primary	Number of THAs revised due to infection					Number of primary
	0–30	31–90	91 days	1–5
THA	days	days	–1 year	years	Total (%)	THAs
2005	6	4	8	15	46 (0.9)	5,849
2006	10	6	6	23	55 (1.2)	5,816
2007	23	9	4	22	74 (1.2)	6,099
2008	30	10	10	17	78 (1.4)	6,327
2009	34	12	13	17	95 (1.5)	6,577
2010	53	11	10	18	98 (1.6)	6,722
2011	71	8	7	17	111 (1.3)	6,783
2012	54	10	13	16	98 (1.3)	7,272
2013	58	11	11	14	96 (1.3)	7,228
2014	47	14	11	11	84 (1.1)	7,333
2015	60	17	14	n.a.	n.a.	7,705
2016	65	18	17	n.a.	n.a.	8,247
2017	64	15	20	n.a.	n.a.	8,539
2018	72	16	12	n.a.	n.a.	9,053
2019	n.a.	n.a.	n.a.	n.a.	n.a.	9,304

n.a. = not applicable due to incomplete follow-up

Figure 3. The relationship between HRR of revision due to infection and time­span postoperatively after primary THAs for the period 2010–2014 (red line) and 2015–2019 (green line) compared with 2005–2009 (blue lines). Smoothed Schoenfeld residuals adjusted for sex, age, ASA class, indication for primary THA, duration of surgery, surgical approach, and modularity of the THA (solid lines) with 95% confidence intervals (broken lines).