Functional performance of mobile versus fixed bearing total knee prostheses: a randomised controlled trial

PURPOSE: The primary goal of this study was to assess the difference in active flexion between patients with a mobile versus a fixed bearing, cruciate retaining, and total knee arthroplasty. The study was designed as a randomised controlled multi-centre trial. METHODS: Participants were assigned to interventions by using block-stratified, random allocation. Outcome parameters were active flexion, passive flexion, and Knee Society Score (KSS). Outcome parameters were assessed preoperatively and at 3, 6, and 12 months postoperatively by an independent nurse. RESULTS: Ninety-two patients from one centre were included, 46 in each group. Active flexion was comparable for the two groups, 99.9° for the mobile bearing group and 101° for the fixed bearing group with a baseline controlled difference of 1.0 (95% CI −3.9 to 5.8, n.s.). The Clinical KSS was comparable between the two bearing groups (Mobile 90.0 vs. fixed 92.4, n.s.). The functional KSS showed a difference that was attributable to the stair climbing subscore, which showed a difference in favour of the fixed bearing design between preoperative and 3 months (7.3 point difference; 95% CI 2.3–12.5; P = 0.005) as well as 12 months (4.8 point difference; 95% CI 0.1–9.6; P = 0.045). CONCLUSIONS: There were no short-term differences in active flexion between fixed bearing and mobile bearing total knee arthroplasty. LEVEL OF EVIDENCE: I

Increasing the information provided by probabilistic sensitivity analysis:The relative density plot

Background Results of probabilistic sensitivity analyses (PSA) are frequently visualized as a scatterplot, which is limited through overdrawing and a lack of insight in relative density. To overcome these limitations, we have developed the Relative Density plot (PSA-ReD). Methods The PSA-ReD combines a density plot and a contour plot to visualize and quantify PSA results. Relative density, depicted using a color gradient, is transformed to a cumulative probability. Contours are then plotted over regions with a specific cumulative probability. We use two real-world case studies to demonstrate the value of the PSA-ReD plot. Results The PSA-ReD method demonstrates proof-of-concept and feasibility. In the real-world case-studies, PSA-ReD provided additional visual information that could not be understood from the traditional scatterplot. High density areas were identified by color-coding and the contour plot allowed for quantification of PSA iterations within areas of the cost-effectiveness plane, diminishing overdrawing and putting infrequent iterations in perspective. Critically, the PSA-ReD plot informs modellers about non-linearities within their model. Conclusions The PSA-ReD plot is easy to implement, presents more of the information enclosed in PSA data, and prevents inappropriate interpretation of PSA results. It gives modelers additional insight in model functioning and the distribution of uncertainty around the cost-effectiveness estimate

Inhibition of dendritic cell activation and modulation of T cell polarization by the platelet secretome

Platelet transfusions are a frequently administered therapy for especially hemato-oncological patients with thrombocytopenia. Next to their primary function in hemostasis, currently there is increased attention for the capacity of platelets to affect the function of various cells of the immune system. Here, we investigate the capacity of platelets to immuno-modulate monocyte-derived dendritic cells (moDC) as well as primary dendritic cells and effects on subsequent T cell responses. Platelets significantly inhibited pro-inflammatory (IL-12, IL-6, TNF alpha) and increased anti-inflammatory (IL-10) cytokine production of moDCs primed with toll-like receptor (TLR)-dependent and TLR-independent stimuli. Transwell assays and ultracentrifugation revealed that a soluble factor secreted by platelets, but not microvesicles, inhibited DC activation. Interestingly, platelet-derived soluble mediators also inhibited cytokine production by human ex vivo stimulated myeloid CD1c+ conventional DC2. Moreover, platelets and platelet-derived soluble mediators inhibited T cell priming and T helper differentiation toward an IFN gamma+ Th1 phenotype by moDCs. Overall, these results show that platelets are able to inhibit the pro-inflammatory properties of DCs, and may even induce an anti-inflammatory DC phenotype, with decreased T cell priming capacity by the DC. The results of this study provide more insight in the potential role of platelets in immune modulation, especially in the context of platelet transfusions.Immunobiology of allogeneic stem cell transplantation and immunotherapy of hematological disease

Storage-Induced Platelet Apoptosis Is a Potential Risk Factor for Alloimmunization Upon Platelet Transfusion

Stemcel biology/Regenerative medicine (incl. bloodtransfusion