A matched comparison of the patient-reported outcome measures of 38,716 total and unicompartmental knee replacements:an analysis of linked data from the National Joint Registry of England, Northern Ireland and Isle of Man and England’s National PROM collection programme

Background and purpose — The surgical treatment options for severe knee osteoarthritis are unicompartmental (UKR) and total knee replacement (TKR). For patients, functional outcomes are more important than revision rate. We compared the patient-reported outcome measures (PROMs) of both implant types using a large PROMs dataset. Patients and methods — We analysed a propensity-matched comparison of 38,716 knee replacements (19,358 UKRs and 19,358 TKRs) enrolled in the National Joint Registry and the English National PROM collection programme. Subgroup analyses were performed in different age groups. Results — 6-month postoperative Oxford Knee Score (OKS) for UKR and TKR were 38 (SD 9.4) and 36 (SD 9.4) respectively. A higher proportion of UKRs had an excellent OKS (≥ 41) compared with TKR (47% vs 36%) and a lower proportion of poor OKS (< 27) scores (13% vs. 16%). The 6-month OKS was higher in all age groups for UKR compared with TKR, with the difference increasing in older age groups. The mean 6-month EQ-5D score was 0.78 (SD 0.25) and 0.75 (SD 0.25) respectively. The improvement in EQ-5D resulting from surgery was higher for UKR than TKR both overall and in all age groups. All comparisons were statistically significant (p < 0.05). Interpretation — UKR had a greater proportion of excellent OKS scores and lower proportion of poor scores than TKR. Additionally, the quality of life was higher for UKR compared with TKR. These factors should be balanced against the higher revision rate for UKR when choosing which procedure to perform

A matched comparison of the patient-reported outcome measures of cemented and cementless total knee replacements, based on the National Joint Registry of England, Wales, Northern Ireland, and Isle of Man and England’s National PROM collection programme

BACKGROUND AND PURPOSE: Total knee replacement (TKR) can be implanted with or without bone cement. It is currently unknown how the functional outcomes compare. Therefore, we compared the patient-reported outcome measures (PROMS) of both fixation methods. PATIENTS AND METHODS: We performed a propensity-matched comparison of 14,404 TKRs (7,202 cemented and 7,202 cementless) enrolled in the National Joint Registry and the English National PROMs collection programme. Subgroup analyses were performed in different age groups (1) < 55 years; (2) 55–64 years; (3) 65–74 years; (4) ≥ 75 years. RESULTS: The 6-month postoperative Oxford Knee Score (OKS) was significantly (p < 0.001) higher for cemented TKR (35, SD 9.7) than cementless TKR (34, SD 9.9). The OKS was also significantly higher for the cemented TKR in all age groups, except the 55–64-year group. A significantly higher proportion of cemented TKRs had an excellent OKS (≥ 41) compared with cementless (32% vs. 28%, p < 0.001) and a lower proportion of poor (< 27) scores (19% vs. 22%, p = 0.001). This was also observed for all age subgroups. There were no significant differences in EQ-5D points gained postoperatively between the groups respectively (0.31 vs. 0.30, p = 0.1). INTERPRETATION: Cemented TKRs had a greater proportion of excellent OKS scores and lower proportion of poor scores both overall and across all age groups. However, the absolute differences are small and below the minimally clinically important difference, making both fixation types acceptable. Currently the vast majority of TKRs are cemented and the results from this study suggest that this is appropriate

A matched comparison of cementless unicompartmental and total knee replacement outcomes based on the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man

BACKGROUND AND PURPOSE: The main treatments for severe medial compartment knee arthritis are unicompartmental (UKR) and total knee replacement (TKR). UKRs have higher revision rates, particularly for aseptic loosening, therefore the cementless version was introduced. We compared the outcomes of matched cementless UKRs and TKRs. PATIENTS AND METHODS: The National Joint Registry was linked to the English Hospital Episode Statistics and Patient Reported Outcome Measures (PROMs) databases. 10,552 cementless UKRs and 10,552 TKRs were propensity matched and regression analysis used to compare revision/reoperation risks. 6-month PROMs were compared. UKR results were stratified by surgeon caseload into low- (< 10 UKRs/year), medium- (10 to < 30 UKRs/year), and high-volume (≥ 30 UKRs/year). RESULTS: 8-year cementless UKR revision survival for the 3 respective caseloads were 90% (95% CI 87–93), 93% (CI 91–95), and 96% (CI 94–97). 8-year reoperation survivals were 76% (CI 71–80), 81% (CI 78–85), and 84% (CI 82–86) respectively. For TKR the 8-year implant survivals for revision and reoperation were 96% (CI 95–97) and 81% (CI 80–83). The HRs for the 3 caseload groups compared with TKR for revision were 2.0 (CI 1.3–2.9), 2.0 (CI 1.6–2.7), and 1.0 (CI 0.8–1.3) and for reoperation were 1.2 (CI 1.0–1.4), 0.9 (CI 0.8–1.0), and 0.6 (CI 0.5–0.7). 6-month Oxford Knee Score (OKS) (39 vs. 37) and EQ-5D (0.80 vs. 0.77) were higher (p < 0.001) for the cementless UKR. INTERPRETATION: Cementless UKRs have higher revision and reoperation rates than TKR for low-volume UKR surgeons, similar reoperation but higher revision rates for mid-volume surgeons, and lower reoperation and similar revision rates for high-volume surgeons. Cementless UKR also had better PROMs

BEM-FEM of Coupling for Prosthetic Socket

In this study, the investigating of the mechanical interaction between the residual limb and its prosthetic socket, and in computer-aided design and computer-aided manufacturing of prosthetic sockets is solving numerically by using FEM-BEM coupling approach. This work tried to improve the deflection of the loading of Socket. The BEM techniques has been used to estimate a deflection at each distance for the main part of loading  that applied on Socket .In addition, a simplified stiffener has been added to optimize a moment of inertia of this main part thereby the deflection will be better , for this purpose a case study has been considered according to international standard for the Socket specification that investigated to illustrate the goal of this work Moreover, a physical problem governed by a linear elliptic partial deferential equation but with a socket (where this paper approximate Socket to shell ) discontinuity in the domain cannot be efficiently solved using the traditional boundary element method. This paper also shows how the Laplace equation can be solved in an interior region containing shell discontinuities by recasting it as an integral equation known as a boundary and shell integral equation and applying collocation to derive a method termed the boundary and Socket element method. Direct and indirect methods are derived and applied to a test problem.  The results show that using stabilized method enables us to get stable and accurate numerical approximations consistent with the physical configuration of the problem over rough mesh by using ANSYS Workbench 14.0 ,AutoCAD and COMSOL 5.2. Keywords: Finite element model; boundary element method; discontinuity; Socke

Computer-aided approaches reveal trihydroxychroman and pyrazolone derivatives as potential inhibitors of SARS-CoV-2 virus main protease

COVID-19 was declared a pandemic by the World Health Organization (WHO) in March 2020. The disease is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The aim of this study is to target the SARS-CoV-2 virus main protease (Mpro) via structure-based virtual screening. Consequently, > 580,000 ligands were processed via several filtration and docking steps, then the top 21 compounds were analysed extensively via MM-GBSA scoring and molecular dynamic simulations. Interestingly, the top compounds showed favorable binding energies and binding patterns to the protease enzyme, forming interactions with several key residues. Trihydroxychroman and pyrazolone derivatives, SN02 and SN18 ligands, exhibited very promising binding modes along with the best MM-GBSA scoring of –40.9 and –41.2 kcal mol–1, resp. Hence, MD simulations for the ligand-protein complexes of SN02 and SN18 affirmed the previously attained results of the potential inhibition activity of these two ligands. These potential inhibitors can be the starting point for further studies to pave way for the discovery of new antiviral drugs for SARS-CoV-2

The effect of surgeon caseload on the relative revision rate of cemented and cementless Unicompartmental Knee Replacements:An analysis from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man

Background: Unicompartmental knee replacement (UKR) offers substantial benefits compared with total knee replacement (TKR) but is associated with higher revision rates. Data from registries suggest that revision rates for cementless UKR implants are lower than those for cemented implants. It is not known how much of this difference is due to the implant or to other factors, such as a greater proportion of high-volume surgeons using cementless implants. We aimed to determine the effect of surgeon caseload on the revision rate of matched cemented and cementless UKRs. Methods: From a group of 40,522 Oxford (Zimmer Biomet) UKR implants (30,814 cemented, 9,708 cementless) recorded in the National Joint Registry, 14,814 (7,407 cemented, 7,407 cementless) were propensity-score matched. Surgeons were categorized into 3 groups: low volume ( Results: The 10-year survival rates for unmatched cementless and cemented UKR implants were 93.3% (95% confidence interval [CI] = 89.8% to 95.7%) and 89.1% (95% CI = 88.6% to 89.6%), respectively, with the difference being significant (hazard ratio [HR] = 0.59; p Conclusions: Cementless fixation decreased the revision rate by about a quarter, whatever the surgeon caseload. Caseload had a profound effect on implant survival. Low-volume surgeons had a high revision rate with cemented or cementless fixation and therefore should consider either stopping or doing more UKR procedures. High-volume surgeons performing cementless UKR demonstrated a 10-year survival rate of 97.5%, which was similar to that reported in registries for the best-performing TKRs. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.</p

Highly selective and sensitive macrocycle-based dinuclear foldamer for fluorometric and colorimetric sensing of citrate in water.

The selective detection of citrate anions is essential for various biological functions in living systems. A quantitative assessment of citrate is required for the diagnosis of various diseases in the human body; however, it is extremely challenging to develop efficient fluorescence and color-detecting molecular probes for sensing citrate in water. Herein, we report a macrocycle-based dinuclear foldamer (1) assembled with eosin Y (EY) that has been studied for anion binding by fluorescence and colorimetric techniques in water at neutral pH. Results from the fluorescence titrations reveal that the 1·EY ensemble strongly binds citrate anions, showing remarkable selectivity over a wide range of inorganic and carboxylate anions. The addition of citrate anions to the 1·EY adduct led to a large fluorescence enhancement, displaying a detectable color change under both visible and UV light in water up to 2 μmol. The biocompatibility of 1·EY as an intracellular carrier in a biological system was evaluated on primary human foreskin fibroblast (HF) cells, showing an excellent cell viability. The strong binding properties of the ensemble allow it to be used as a highly sensitive, detective probe for biologically relevant citrate anions in various applications

A matched comparison of revision rates of cemented Oxford Unicompartmental Knee Replacements with Single and Twin Peg femoral components, based on data from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man

Background and purpose — Registries report high revision rates after unicompartmental knee replacement (UKR) due, in part, to aseptic loosing. In an attempt to improve Oxford UKR femoral component fixation a new design was introduced with a Twin rather than a Single peg. We used the National Joint Registry (NJR) to compare the 5-year outcomes of the Single and Twin Peg cemented Oxford UKRs. Patients and methods — We performed a retrospective observational study using NJR data on propensity score matched Single and Twin Peg UKRs (matched for patient, implant and surgical factors). Data on 2,834 Single Peg and 2,834 Twin Peg were analyzed. Cumulative implant survival was calculated using the Kaplan–Meier method and comparisons between groups performed using Cox regression models. Results — In the matched cohort, the mean follow up for both Single and Twin Peg UKRs was 3.3 (SD 2) and 3.4 years (SD 2) respectively. The 5-year cumulative implant survival rates for Single Peg and Twin Peg were 94.8% (95% CI 93.6–95.8) and 96.2% (CI 95.1–97.1) respectively. Implant revision rates were statistically significantly lower in the Twin Peg (hazard ratio [HR)] = 0.74; p = 0.04). The revision rate for femoral component aseptic loosening decreased significantly (p = 0.03) from 0.4% (n = 11) with the Single Peg to 0.1% (n = 3) with the Twin Peg. The revision rate for pain decreased significantly (p = 0.01) from 0.8% (n = 23) with the Single Peg to 0.3% (n = 9) with the Twin Peg. No other reasons for revision had significant differences in revision rates. Interpretation — The revision rate for the cemented Twin Peg Oxford UKR was 26% less than the Single Peg Oxford UKR. This was mainly because the revision rates for femoral loosening and pain more than halved. This suggests that the Twin Peg component should be used in preference to the Single Peg design.</p

New surgical instrumentation reduces the revision rate of Unicompartmental Knee Replacement:A propensity score matched comparison of 15,906 knees from the National Joint Registry

Background Unicompartmental knee replacement (UKR) offers advantages over total knee replacement but has higher revision rates. New instrumentation known as Microplasty was introduced to address this. The aim was to compare the revision rates of UKRs implanted with Microplasty and traditional instrumentation (Non-Microplasty). Methods National Joint Registry (NJR) data was used to propensity score match 15,906 UKRs (7953 Microplasty and 7953 Non-Microplasty) for important patient, implant and surgical factors. Implant survival rates were determined using the Kaplan–Meier method and compared using Cox regression models in a multilevel model. Results The five-year implant survival for Microplasty and Non-Microplasty UKRs were 96.7% (95% CI: 96.0%–97.2%) and 94.5% (CI: 93.8–95.1%), respectively. The revision rate for Microplasty UKR was significantly lower than that of Non-Microplasty UKRs (hazard ratio [HR] = 0.77, p = 0.008). Compared with Non-Microplasty UKRs, the revision rate of Microplasty UKRs implanted during the year after the introduction of Microplasty was lower, but the difference was not significant (HR: 0.86, CI: 0.67–1.10, p = 0.23), whereas for those implanted more than a year after introduction, the difference was significant (HR: 0.69, CI: 0.54–0.89, p = 0.004). Conclusion The use of Microplasty instrumentation has resulted in an improved five-year UKR survival. Microplasty UKR implanted during the first year after introduction had a small, non-significant decrease in revision rate. As the revision rate did not increase, this suggests that there is no adverse learning curve effect. Microplasty UKRs implanted after this transition period had a revision rate 31% lower than the Non-Microplasty group. Level of evidence II.</p