Risk factors and a prognostic model of hip periprosthetic infection recurrence after surgical treatment using articulating and non-articulating spacers.

PURPOSE

The purpose of this study was evaluation of the efficacy of the first step of a two-stage procedure for treatment of hip prosthetic joint infection (PJI) using articulating and non-articulating spacers as well as development of a prediction model and prognostic score for infection recurrence.

METHODS

In a cohort of 217 patients treated for PJI of the hip, demographic characteristics, clinical symptoms, body temperature, body mass index (BMI), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), white blood cell count (WBC), microbiological cultures and the type of the spacer used were retrospectively analyzed for association with the recurrence of PJI.

RESULTS

Patients with infection recurrence had increased levels of ESR and CRP (P < 0.001) together with higher BMI and shorter infection manifestation period after previous surgery (P < 0.05). Among these patients, there was no significant difference of clinical characteristics between subjects with articulating and non-articulating spacers. Microbial associations were more often identified in patients with recurrent infection (50 %, P < 0.01) where Gram-negative bacteria were predominant (61.5 %, P < 0.01). These patients had higher percentage of Acinetobacter sp. and P. aeruginosa isolates (28.2 %, P < 0.01).

CONCLUSIONS

Efficacy of the first step of two-stage revision was 64.1 %. Placement of either articulating or non-articulating spacers did not influence recovery from PJI. Laboratory values of ESR, CRP, BMI and the type of previous surgery were identified as main factors that affect outcomes of the two-stage procedure. A prognostic model with the calculation of a total risk score for PJI recurrence was developed.