Patient suffering from pain and color change in her knee 10 years after a total knee replacement diagnosed as metallosis due to failed total knee replacement (TKR).  Beginning: prosthesis fail and implant wearing is a well known and good identified subjects in arthroplasty surgeries. Polyethylene wearing is a common issue but metal wearing and metallosis are rare cases. 

Objective: Recent reports indicate that neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR),mean platelet volume (MPV), and C-reactive protein (CRP) are key markers of systemic inflammation. These markershave also been shown to be significantly increased in patients with psoriasis vulgaris compared to control subjects. Inthis study, we aimed to evaluate the relationship between serum levels of NLR, PLR, MPV, and CRP and nailinvolvement, presence of arthritis, duration of disease, and Psoriasis Area and Severity Index (PASI) scores in patientswith psoriasis vulgaris.Methods: The study included 133 patients with psoriasis vulgaris that had no systemic, infectious, or autoimmunediseases and a control group of 107 healthy volunteers. The patients were divided into two groups based on theirPASI scores: (I) mild (PASI<10) and (II) moderate-severe (PASI≥10).Results: NLR, MPV, and CRP values were significantly higher in the patient group compared to the control group(p=0.001, 0.003, <0.001, respectively). PLR values were lower in the patient group compared to the control groupalthough no significant difference was found (p=0.074). In the patient group, the MPV and CRP values weresignificantly higher in the patients with moderate-severe psoriasis vulgaris compared to the patients with psoriasisvulgaris (p=0.017 and <0.001, respectively). No significant relationship was found between the MPV and CRP valuesand presence of arthritis, nail involvement, and duration of disease (p>0.05). Similarly, no significant relationship wasfound between the NLR and PLR values and PASI score, presence of arthritis, nail involvement, and duration ofdisease (p>0.05).Conclusion: NLR and CRP can be useful markers of inflammation in patients with psoriasis vulgaris; however, theabsence of a correlation between NLR and the severity of disease may lead to a limitation in the clinical use of NLR.MPV can be a better marker of inflammation compared to PLR and NLR since it was significantly higher in the patientswith psoriasis vulgaris compared to the healthy subjects and also correlated with the PASI score.