Approximately 20,000 patients are diagnosed with septic arthritis annually, with 15%
specifically affecting the hip joint. These cases exacerbate arthritic changes, often
warranting a total hip arthroplasty (THA). Given their prior history of infection,
these patients are predisposed to subsequent periprosthetic joint infections (PJIs).
Multiple studies suggest delaying THA after a native septic hip, but no study utilizing
a large cohort examined the specific timing to mitigate post-THA PJI risk within a
short (<1-year) quiescent period after septic arthritis. We sought to compare patients
who were diagnosed with septic hip arthritis at time intervals (0 to 6, or 6 to 12
months) prior to an ipsilateral primary THA to a cohort of THA patients who never
had a septic hip history. Specifically, we assessed: 90-day to 2-year (1) revisions
due to PJI and (2) associated risk factors for PJI at 2-years.
A national, all-payer database was queried to identify all patients who underwent
a primary THA between 2010 to 2021 and patients who had prior ipsilateral septic hip
arthritis were characterized using International Classification of Disease and Current
Practice Terminology codes (n = 1,052). A randomized sample of patients who never
had a history of septic arthritis prior to undergoing THA was used as a non-septic
group comparison (n = 5,000). The incidences of PJI at 90 days through two years were
then identified and compared using bivariate chi-square analyses. Risk factors for post-THA PJIs were then analyzed using multivariate
The septic arthritis cohorts were more likely to require revisions due to PJIs, as
compared to the non-septic group at 90-days, 1-year and 2-years (all p<0.0001). Patients
who were diagnosed with septic arthritis between 0 to 6 months prior to THA were at
greater PJI risk at both one-year (odds ratio (OR) of 43.1 versus 29.6, p<0.0001) and two-years (OR of 38.3 versus 22.1, p<0.0001) compared to patients who had diagnoses between 6 to 12 months. Diabetes mellitus,
obesity, and tobacco use were associated risk factors for PJIs at 2-years in the septic
hip cohort in comparison to the cohort without a septic hip history.
Less than 1-year quiescent period after septic arthritis is associated with at 38
times increased risk and 22 times risk for post-THA PJI, at 0 and 6 months and 6 and
12 months, respectively. Though patients who undergo THA greater than 6 months after
their septic arthritis treatment have a decreased risk compared to those between 0
and 6 months the risks are still high. Orthopaedic surgeons should be aware of the
increased risks of PJIs when consider performing a THA in patients with a history
of septic arthritis.