Aseptic versus septic revision total knee arthroplasty: Patient satisfaction, outcome and quality of life improvement

Abstract

We prospectively compared the clinical outcomes and patient satisfaction rates of aseptic (n = 30) versus septic revision TKA (n = 15) at a mean follow-up of 40 months. We hypothesized that the clinical results of septic revision TKA would be inferior to aseptic revision TKA. The indication for revision in aseptic group was stiffness in 11 patients, aseptic loosening in 13, patellar loosening or maltracking in 6 patients. Patients operated for infection had better post-operative Knee Society Scores (KSS), Function Scores and SF-36 Mental Scores than aseptic group but there were no significant differences in the satisfaction rates. Patients operated for infection had more improvement in their KSS (p = 0.004) and Function Scores (p = 0.02) than patients revised for stiffness. Moreover, patients operated on for patellar problems had higher satisfaction rates than patients revised for stiffness (p = 0.01) or aseptic loosening (p = 0.01). Thus, patients undergoing septic revision TKA had better outcomes compared to those with aseptic revision TKA. However, in the aseptic group, revision TKA for stiffness was associated with the poorest outcomes. The indication for aseptic revision is an important variable when discussing treatment and outcome with patients.

Introduction

Primary total knee arthroplasty has consistently demonstrated good clinical results with survivorship of 90% at 15–20 years follow-up [1], [2], [3], [4]. There has been significant increase in the number of primary total knee arthroplasties [TKA] and this is expected to continue in the future [5]. With this scenario, the number of revision total knee arthroplasties will inevitably increase [5], [6]. Revision total knee arthroplasty presents challenging clinical situations, and the clinical outcome is less satisfactory compared to primary TKA [7], [8], [9], [10].

Revision TKA includes septic and aseptic etiologies. Infection after total knee arthroplasty has been one of the most feared complications. Infection after total knee arthroplasty must be managed expeditiously and involves two components: a] eradication of infection and b] subsequent implantation of a stable and functional implant. The various treatment options for the management of infected total knee arthroplasty include antibiotic suppression, operative debridement with or without polyethylene exchange, exchange arthroplasty, arthrodesis or resection arthroplasty. Two-stage exchange arthroplasty is the gold standard for management of infection after TKA [11], [12], [13], [14], [15], [16], [17], [18]. This procedure is highly successful in controlling infection and restoring function. The results of septic revisions may be influenced by the chronicity of infection or whether infection occurred after primary knee arthroplasty following multiple previous knee operations (arthroscopy, osteotomy), or revision total knee arthroplasty [13].

Aseptic TKA revisions are commonly performed for loosening of the components, wear and osteolysis, stiffness and instability. The outcome of aseptic revision TKA has been variable (48% to 92% success rate) in most series [7], [8], [9], [19], [20], [21], [22]. Hanssen et al. reported less favorable outcome for aseptic revision TKA than for primary TKA [19]. In another study, Friedman et al. concluded that although there was improvement in function and pain after aseptic revision TKA, these improvements were significantly less than that after primary TKA [9]. The clinical results of septic revision TKAs have been observed to be inferior to aseptic revision TKAs in several studies [23], [24], [25].

The purpose of this study was to compare the clinical outcome, patient satisfaction and improvement in the quality of life after septic and aseptic revision total knee arthroplasty. We hypothesized that the clinical results of septic revision TKA would be inferior to those for aseptic revision TKA.