Erratum:

The original version of this article unfortunately contained a mistake in the section entitled “Revision surgery”. The corrected text is given below:

Corrected text:

(Page 5: Results - Revision surgery)

Revision surgery of either hip after the second THA surgery was slightly more common in simultaneously operated patients compared to the patients operated with a staged procedure (Simultaneous surgeries 240 [7.1 %], surgeries within6 months n 495 [5.1 %], surgeries between 7 and 12 months n 828 [5.3 %] and second surgery after >12 months n 3,573 [6.4 %]).

The unadjusted risk of revision for the simultaneously operated patients compared to the patients operated with staged procedure was [HR 1.6, CI 1.3-1.9] (surgeries within 6 months [HR 1.2, CI 1.1-1.4], surgeries between 7 and 12 months [HR 1.1, CI 1.0-1.3] with second surgery after >12 months as the reference group). When adjusting for sex, age, diagnosis and type of prosthesis fixation this difference in the risk estimates disappeared (simultaneous bilateral [HR 1.1, CI 0.9-1.4], surgeries within 6 months [HR 1.1, CI 1.0-1.3], surgeries between 7 and 12 months [HR 1.1, CI 1.0-1.2] with second surgery after >12 months as the reference group).