The Inverse Spacer—A Novel, Safe, and Cost-Effective Approach in Routine Procedures for Revision Knee Arthroplasty

Background: A major disadvantage of current spacers for two-stage revision total knee arthroplasty (R-TKA) is the risk of (sub-) luxation during mobilization in the prosthesis-free interval, limiting their clinical success with detrimental consequences for the patient. The present study introduces a novel inverse spacer, which prevents major complications, such as spacer (sub-) luxations and/or fractures of spacer or bone. Methods: The hand-made inverse spacer consisted of convex tibial and concave femoral components of polymethylmethacrylate bone cement and was intra-operatively molded under maximum longitudinal tension in 5° flexion and 5° valgus position. Both components were equipped with a stem for rotational stability. This spacer was implanted during an R-TKA in 110 knees with diagnosed or suspected periprosthetic infection. Postoperative therapy included a straight leg brace and physiotherapist-guided, crutch-supported mobilization with full sole contact. X-rays were taken before and after prosthesis removal and re-implantation. Results: None of the patients experienced (sub-) luxations/fractures of the spacer, periprosthetic fractures, or soft tissue compromise requiring reoperation. All patients were successfully re-implanted after a prosthesis-free interval of 8 weeks, except for three patients requiring an early exchange of the spacer due to persisting infection. In these cases, the prosthetic-free interval was prolonged for one week. Conclusion: The inverse spacer in conjunction with our routine procedure is a safe and cost-effective alternative to other articulating or static spacers, and allows crutch-supported sole contact mobilization without major post-operative complications. Maximum longitudinal intra-operative tension in 5° flexion and 5° valgus position appears crucial for the success of surgery.

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Revision Total Knee Arthroplasty with Metaphyseal Sleeves without Stem: Short-Term Results

Joints ◽

10.1055/s-0037-1607427 ◽

2017 ◽

Vol 05 (04) ◽

pp. 207-211 ◽

Cited By ~ 13

Author(s):

Giacomo Stefani ◽

Valerio Mattiuzzo ◽

Greta Prestini

Keyword(s):

Total Knee Arthroplasty ◽

Retrospective Study ◽

Knee Arthroplasty ◽

Bone Ingrowth ◽

Womac Score ◽

Revision Total Knee Arthroplasty ◽

X Rays ◽

Short Term ◽

Total Knee ◽

Baseline Values

Purpose The aim of this study was to evaluate the efficacy of revision total knee arthroplasty (TKA) with cementless metaphyseal sleeves without stems either in the femoral or tibial side or in both. Methods In this retrospective study, 51 patients (51 knees) operated in the period 2010 to 2015 met the above-mentioned criteria and were invited to a medical examination including X-rays. Forty-six were available for the study. Mean follow-up was 37 months. Knee Society score (KSS) (objective knee score), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and range of motion (ROM) were used as outcome scores and compared with baseline values. X-rays were also examined and compared with postoperative exams to evaluate the presence of loosening, radiolucent lines, and bone ingrowth. Satisfaction of the patients was also investigated using a linear scale from 1 to 10. Results KSS improved from 39 to 77 (p < 0.01); WOMAC score improved from 76 to 41 (p < 0.01). Twenty-four (52%) patients were satisfied, 15 (32%) were partially satisfied, and 7 (16%) were unsatisfied. ROM improved from 93 to 96 degrees (nonsignificant difference). X-rays showed no loosening of the implants, radiolucent lines in 4 patients (3 of them were asymptomatic) and bone ingrowth in 43 out of 46 patients. Conclusion In this short-term retrospective study, the use of sleeves without stem was a safe and effective procedure in revision TKA. We found a significant improvement in clinical results compared with baseline values and no signs of implant loosening. Level of Evidence Level IV, therapeutic case series.

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Improving patient flow in acute psychiatric wards: enhanced bed management and trusted assessment

BJPsych Bulletin ◽

10.1192/bjb.2020.12 ◽

2020 ◽

Vol 44 (4) ◽

pp. 159-162

Author(s):

Douglas Turkington ◽

Steve Moorhead ◽

Gordon D. Turkington ◽

Carla King ◽

Leigh Bell ◽

...

Keyword(s):

Mental Health ◽

Patient Flow ◽

Cost Effective ◽

Management Team ◽

Bed Management ◽

Cost Effective Approach ◽

Before And After ◽

Acute Psychiatric Wards ◽

Two Measures ◽

Out Of Area

Aims and methodIn three localities in a mental health trust in England, an enhanced bed management team was established to improve patient flow and reduce out-of-area placements. Trusted assessments were provided to support risk management and conflict resolution. Two measures of flow were compared before and after the team was established.ResultsThe trusted assessment recommendation was for discharge in 70% of cases. The number of out-of-area placements was significantly reduced (P < 0.05), saving £616 876 over a 12-month period. Patient flow was significantly improved in one of the three localities as measured by patients/bed/6-month period (P < 0.05). In one of the other localities increased use of trusted assessment input and reduced numbers of patients being transferred in are recommended to improve flow.Clinical implicationsMental health trusts should consider the establishment of an enhanced bed management team, including trusted assessment, as a safe and cost-effective approach to improving patient flow and reducing the need for out-of-area placement.

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Investigating the effects of COVID-19 to crime rates through a geospatial approach: the case of New York, USA

10.5194/egusphere-egu21-15125 ◽

2021 ◽

Author(s):

Ioanna Tselka ◽

Isidora Isis Demertzi ◽

George P. Petropoulos

Keyword(s):

New York ◽

Scientific Evidence ◽

Cost Effective ◽

Crime Rates ◽

Added Value ◽

Web Gis ◽

Study Region ◽

Cost Effective Approach ◽

Before And After ◽

The Impact

Covid-19 pandemic has led to severe consequences to humanity worldwide. Yet, to our knowledge, little scientific evidence is available exploring the impact of the pandemic on criminality. Thus, it is imperative to examine their relationships spatially to obtain a better understanding of societal characteristics during the pandemic.This study aims at demonstrating the use of geoinformation in analyzing the spatial patterns between crime properties and Covid-19 spread using as a case study New York City, USA, one of the largest metropolitan cities of the world. To address our objectives, geostatistical analysis and data visualization methods have been implemented in real-world crime data acquired from a web-GIS platform. Our analysis concerns two equal time periods before and after the lockdown implementation.Results revealed some very interesting patterns spatially between the examined parameters and societal characteristics existing in the study region. The methodological framework presented underlined the added value of geoinformation as a robust and cost-effective approach in examining the impact of the pandemic to the society.&#160;Keywords: Covid-19, pandemic, crime rates, geoinformation, New York

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Investigation of Bone Density Evolution Before and After Total Knee Arthroplasty Using a Thermodynamic-Based Framework

10.32920/ryerson.14651895.v1 ◽

2021 ◽

Author(s):

Saeid Nazgooei

Keyword(s):

Total Knee Arthroplasty ◽

Bone Density ◽

Density Distribution ◽

Knee Arthroplasty ◽

Fe Model ◽

X Rays ◽

Femoral Bone ◽

Density Evolution ◽

Before And After ◽

Total Knee

In this study, a new bone remodeling model which combines mechanical loading and bone metabolism factors is used to predict the evolution of bone density after Total Knee Arthroplasty (TKA). A 3D finite element (FE) model of the distal femoral bone, coupled with a new thermodynamic-based theory (BRT), was developed in ANSYS. An axial load of 3000N was applied to the FE model, and the bone density distribution in the femoral bone was calculated. The results were then compared with those obtained from the strain energy density (SED) model and the clinical observations. This comparison showed that the bone density distribution predicted by the thermodynamic-based model before and after TKA is consistent with the structure of the distal femur obtained from X-rays. Furthermore, the predicted bone density distribution using BRT showed a gradual and uniform evolution contrary to the SED model, where there is no gradual bone density evolution.

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Investigation of Bone Density Evolution Before and After Total Knee Arthroplasty Using a Thermodynamic-Based Framework

10.32920/ryerson.14651895 ◽

2021 ◽

Author(s):

Saeid Nazgooei

Keyword(s):

Total Knee Arthroplasty ◽

Bone Density ◽

Density Distribution ◽

Knee Arthroplasty ◽

Fe Model ◽

X Rays ◽

Femoral Bone ◽

Density Evolution ◽

Before And After ◽

Total Knee

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Porous-Coated Metaphyseal Sleeves in Revision Total Knee Arthroplasty: Midterm Results

Joints ◽

10.1055/s-0041-1730377 ◽

2021 ◽

Author(s):

Giacomo Stefani ◽

Valerio Mattiuzzo ◽

Greta Prestini ◽

Carolina Civitenga ◽

Roberto Calafiore ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Bone Ingrowth ◽

Clinical Results ◽

Revision Total Knee Arthroplasty ◽

X Rays ◽

Radiographic Findings ◽

Radiolucent Lines ◽

Total Knee

Abstract Purpose The aim of this study was to evaluate the efficacy in terms of clinical results and radiographic findings of using metaphyseal sleeves in revision total knee arthroplasty (TKA), and to check if the use of sleeves without stems did not impair such results. Methods In this retrospective study, 141 patients (143 knees) operated in the period 2008 to 2015 met the above-mentioned criteria and were invited to a medical examination including X-rays. A total of 121 knees were available for the study (44 in the group without stems and 77 in the group with stems). Mean follow-up was 63 months for the stemless group and 89 for the group with stems. Knee Society Score (KSS) (objective knee score) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were used as outcome scores and compared with baseline values, range of motion (ROM) was also compared with preop value and X-rays were also examined and compared with immediate postop X-rays to check signs of loosening and radiolucent lines, if any, and bone ingrowth. Satisfaction of the patients was also investigated using a linear scale from 1 to 10. Results KSS improved from 34 to 81 postop (39 to 81 in the stemless group) (p < 0.01), while WOMAC from 82% preop to 39% postop (76 to 37% in the stemless group) (p < 0.01). Forty-six patients were satisfied, 20 partially satisfied, and 11 unsatisfied (respectively 25–14–5 in the stemless group). ROM improved from 89 degrees preop to 99 degrees postop (93 to 98 degrees in the stemless group). X-rays showed no loosening of the implant, radiolucent lines in 8 patients, and bone ingrowth in 113 out of 121 patients. Conclusion In this midterm follow-up study, we found a significant improvement in clinical results compared with preop values. We found no difference between the two groups (with and without stems) thus suggesting that the use of stemless sleeves does not impair results in revision TKA. Level of Evidence Therapeutic case series, level IV.

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The Clinical, Roentgenological and Morphological Effects of an Acute Exposure of Phosgene on the Lungs of Dogs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065237 ◽

1971 ◽

Vol 29 ◽

pp. 236-237

Author(s):

R. F. Bils ◽

W. F. Diller ◽

F. Huth

Keyword(s):

Latent Period ◽

Chemical Industry ◽

Toxic Substance ◽

Lung Edema ◽

X Rays ◽

Beagle Dogs ◽

Male And Female ◽

Morphological Alterations ◽

Before And After ◽

Electron Microscopes

Phosgene still plays an important role as a toxic substance in the chemical industry. Thiess (1968) recently reported observations on numerous cases of phosgene poisoning. A serious difficulty in the clinical handling of phosgene poisoning cases is a relatively long latent period, up to 12 hours, with no obvious signs of severity. At about 12 hours heavy lung edema appears suddenly, however changes can be seen in routine X-rays taken after only a few hours' exposure (Diller et al., 1969). This study was undertaken to correlate these early changes seen by the roengenologist with morphological alterations in the lungs seen in the'light and electron microscopes.Forty-two adult male and female Beagle dogs were selected for these exposure experiments. Treated animals were exposed to 94.5-107-5 ppm phosgene for 10 min. in a 15 m3 chamber. Roentgenograms were made of the thorax of each animal before and after exposure, up to 24 hrs.

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