Can neutrophil-to-lymphocyte, platelet-to-lymphocyte and monocyte-to-lymphocyte ratios be useful to the diagnosis of aseptic loosening after total knee arthroplasty?

ABSTRACT

BACKGROUND: The aim of this study is to determine the role of hematological parameters - neutrophil/lymphocyte, platelet/lymphocyte, and monocyte/lymphocyte ratios - in the diagnosis of aseptic loosening after total knee arthroplasty. METHODS: This study retrospectively analyzed the data of 244 patients who had primary total knee arthroplasty and 66 patients with aseptic loosening developed after total knee arthroplasty. The white blood cell counts, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, monocyte/lymphocyte ratio and c-reactive protein levels in both groups were determined using the results of venous blood samples collected during preoperative preparation and compared between the groups. RESULTS: Our study findings reveal that the monocyte/lymphocyte ratio of the group with aseptic loosening was statistically significantly different from that of the patient group who had primary total knee arthroplasty (p=0.02). Furthermore, although c-reactive protein levels are not high enough to suggest systemic inflammation, the difference between the groups is statistically significant (p=0.01). CONCLUSIONS: No hematological parameter that could be used in the diagnosis of aseptic loosening has been defined in the literature so far. This study demonstrated that the monocyte/lymphocyte ratio could be a helpful parameter in the diagnosis of aseptic loosening (Tab. 1, Fig. 1, Ref. 28).