Aseptic Loosening of Total Hip Arthroplasty: Infection Always Should be Ruled Out

Abstract

Background It is believed that some cases of aseptic failure of THA may be attributable to occult infections. However, it is unclear whether preoperative erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are more likely elevated in these patients than those without overt infection. Questions/purposes We asked whether some patients with aseptic THA failures have abnormal serologic indicators of periprosthetic joint infection (PJI) at the time of revision, namely ESR and/or CRP. Methods Three hundred twenty-three revision THAs for aseptic loosening from 2004 to 2007 were retrospectively evaluated. We categorized all cases into two groups:(1) those with overt PJI (n = 14) plus patients who had a positive intraoperative culture during the index revision (n = 13) and (2) those who did not require rerevision (n = 276) or required surgery for noninfected causes (n = 20). Mean and frequency of abnormal ESR and CRP were compared between the two groups. The minimum followup was 11 months (average, 35 months; range, 11-54 months). Results The mean and frequency of abnormal CRP in first group (n = 27) at 2.1 mg/dL and 48% respectively, were greater than those of the uninfected (n = 296) at 1.2 mg/dL and 27%, respectively. However, there were no differences between two groups regarding mean or frequency of abnormal ESR.

The Routine Use of Atypical Cultures in Presumed Aseptic Revisions Is Unnecessary

“…Before every hip and knee arthroplasty revision, Parvizi et al [15] recommended patients be evaluated for the presence of infection. However, a negative preoperative workup does not completely eliminate the possibility of occult infection [6,13,14,19,20].…”

Swab Cultures Are Not As Effective As Tissue Cultures for Diagnosis of Periprosthetic Joint Infection

“…However, we opted to grow cultures from aseptic cases for less than 2 weeks due to concerns of contaminant growth and thus overly inflated false-positive results. Second, several studies [11,17,20] have recently debated categorizing all aseptic revisions as truly aseptic, especially if there is positive intraoperative culture growth and subsequent need for rerevision due to infection. Although it is Table 3.…”

Successful Identification of Pathogens by Polymerase Chain Reaction (PCR)-Based Electron Spray Ionization Time-of-Flight Mass Spectrometry (ESI-TOF-MS) in Culture-Negative Periprosthetic Joint Infection

“…These results suggest that our ability to detect bacteria associated with a joint is not always indicative of overt disease. In attempting to make clinical sense of these findings, we note that several studies have suggested that subclinical infections may progress very slowly, without the production of standard inflammatory markers or culturable bacteria, yet may still result in pathology that requires joint replacement [27][28][29][30] . Ince et al attempted to use PCR and conventional culture to establish the presence of such ''subclinical'' infection in patients in whom an acetabular cup underwent revision for an apparently aseptic cause; however, an organism could be identified in only one of twenty-four cases 31 .…”

“…It remains possible that some of the patients in the ostensibly uninfected group in our cohort in fact had long-standing occult infections 30 . At least one of these patients (in whom the Ibis identified both the mecA gene and Staphylococcus species) required an irrigation and debridement for periprosthetic joint infection six months after her first revision arthroplasty.…”