Costs of Digital Adherence Technologies for Tuberculosis Treatment Support, 2018-2021.

Digital adherence technologies are increasingly used to support tuberculosis (TB) treatment adherence. Using microcosting, we estimated healthcare system costs (in 2022 US dollars) of 2 digital adherence technologies, 99DOTS medication sleeves and video-observed therapy (VOT), implemented in demonstration projects during 2018-2021. We also obtained cost estimates for standard directly observed therapy (DOT). Estimated per-person costs of 99DOTS for drug-sensitive TB were $98 in Bangladesh (n = 719), $119 in the Philippines (n = 396), and $174 in Tanzania (n = 976). Estimated per-person costs of VOT were $1,154 in Haiti (87 drug-sensitive), $304 in Moldova (173 drug-sensitive), $452 in Moldova (135 drug-resistant), and $661 in the Philippines (110 drug-resistant). 99DOTS costs may be similar to or less expensive than standard DOT. VOT is more expensive, although in some settings, labor cost offsets or economies of scale may yield savings. 99DOTS and VOT may yield savings to local programs if donors cover infrastructure costs.

Effectiveness of bedside staplers in bariatric robotic procedures.

BACKGROUND: Few studies have evaluated the use of laparoscopic staplers in robotic procedures (bedside stapling, BS). This study aims to evaluate the effectiveness of BS compared with robotic staplers (RS) in bariatric robotic procedures. METHODS: Patients who underwent robotic sleeve gastrectomy or gastric bypass elective procedures between 1/1/2021 and 12/31/2021 were extracted from PINC AI™ Healthcare Data. The following clinical outcomes were compared: blood transfusion, bleeding, anastomotic leak, intensive care unit (ICU) visit, and 30-day readmission, operating room (OR) time, inpatient costs, and length of stay. We evaluated baseline balance in BS and RS and bivariate association between covariates and outcomes using Chi-square or Fisher exact test and t-test or ANOVA. Multivariable general linear mixed models (GLMMs) with respective gamma or binomial distribution and log-link function were used to obtain adjusted outcomes variations between BS and RS. RESULTS: Total of 7268 discharges were included with 1603 (22.1%) BS and 5665 (77.9%) RS cases. RS cases consisted of a higher number of patients who were Hispanic (17.0% vs. 9.4%), had Medicaid (26.9% vs. 19.4%) and underwent sleeve gastrectomy (68.4% vs. 53.5%). Higher proportions of RS cases were done by providers in Northeast region (35.5% vs. 24.3%), smaller size (< 500 beds; 71.1% vs. 52.3%), and teaching hospitals (59.4% vs. 39%). The adjusted outcomes variations demonstrated that patients that had RS were significantly more likely to have blood transfusions, ICU stays, increased ORT (19 min) and costs ($1273). Sensitivity analysis showed similar results, except no significant differences in blood transfusion rates in both groups. CONCLUSIONS: Bedside staplers significantly reduce healthcare resource utilization with equivalent effectiveness and fewer ICU stays compared to robotic staplers.

Tips and Tricks to Save You During Revision Total Knee Arthroplasty.

The number of revision total knee arthroplasties (TKAs) performed annually continues to rise. This article is a summary of a symposium on revision TKAs presented at the 2023 American Association of Hip and Knee Surgeons annual meeting. It will provide an overview of the surgical tips and tricks for exposure and component removal, use of metaphyseal fixation and stems to manage bone loss and optimize fixation, constraint in TKA, as well as how to manage extensor mechanism disruptions with a synthetic mesh reconstruction. LEVEL OF EVIDENCE: V.

Metaphyseal Fixation Using Cones and Sleeves for Severe Proximal Tibial Bone Loss.

BACKGROUND: Tibial bone defects are commonly encountered in revision total knee arthroplasty (rTKA) and can be managed with metaphyseal cones or sleeves. Few studies have directly compared tibial cones and sleeves in rTKA, and none have limited this comparison to the most severe tibial defects. The purpose of this study was to evaluate and compare the outcomes of metaphyseal cones and sleeves for tibial reconstruction in rTKA regarding implant fixation and clinical outcomes. METHODS: A retrospective review was conducted on patients undergoing rTKA in which metaphyseal cones or sleeves were utilized for addressing metaphyseal bone loss (34 cones and 18 sleeves). Tibial bone loss was classified according to the Anderson Orthopaedic Research Institute bone defect classification, with types 2B and 3 being included. Patient-reported outcomes and postoperative complications were collected, and a radiographic evaluation of osseointegration or loosening was performed. RESULTS: There were 52 knees included (34 cones, 18 sleeves), with a median follow-up of 41.0 months. All-cause implant survival was 100% at 2 years and 96% (95% confidence interval: 76 to 99%) at 4 years, with 98% of tibial components demonstrating osseointegration at the final follow-up. During follow-up, there were a total 11 revisions, of which 1 sleeve was revised secondary to implant loosening. Tibial sleeves had a higher risk of revision compared to tibial cones (P < .01), and sleeves fixed with a hybrid technique were more likely to need revision than cones fixed by the same method (P = .01). CONCLUSIONS: Porous metaphyseal tibial cones and tibial metaphyseal sleeves both performed well at a 41-month median follow-up with no difference in aseptic survivorship between the 2 constructs. Both demonstrate high rates of osseointegration, low rates of aseptic failure, and significant improvement in Knee Society Scores in patients with severe tibial defects in rTKA.

Metaphyseal cones and sleeves are similar in improving short- and mid-term outcomes in Total Knee Arthroplasty revisions.

PURPOSE: The purpose of this systematic review and metanalysis was to assess clinical and radiological outcomes of metaphyseal sleeves and cones and to identify their possible advantages and disadvantages. METHODS: A comprehensive search from the inception of the databases to March 2021 was performed on Medline, Scopus, CINAHL, Cochrane, Embase, Ovid, and Google scholar databases. Coleman Methodology Score was used for quality assessment. Author, year of publication, type of study, level of evidence, sample size, number of patients, number of knees treated, mean age, gender, mean follow-up, clinical outcomes, complications, the reason for revision and, type of prosthesis were extracted for analysis. Clinical studies providing data about patient's outcomes after the primary and Total Knee Arthroplasty revision with the usage of sleeves or cones and a minimum of 2 years of follow-up were included. RESULTS: The literature search and cross-referencing resulted in a total of 93 articles, but only 30 articles were appropriate for the systematic review. Comparable clinical results were reported between cones and sleeves. The meta-analysis showed a greater incidence of intraoperative fractures in patients treated with sleeves (1.6%, [95% CI 0.7; 3.4] in cones and 4.6%, [95% CI 3.3; 6.4] in sleeves, p = 0.01), while the risk of postoperative fractures (4.3%, [95% CI 2.7; 7] in cones and 2.1%, [95% CI 1.2; 3.5] in sleeves, p = 0.04) and infections (8.5%, [95% CI 6; 12] in cones and 3.7%, [95% CI 2.1; 7.3] in sleeves, p = 0.03) was higher with cones. CONCLUSION: A higher incidence of intraoperative fracture was reported in patients treated with sleeves, while a higher rate of postoperative fractures and infections was described in patients treated with cones. Nonetheless, complications were reported in both groups. LEVEL OF EVIDENCE: III.

Cones and sleeves present good survival and clinical outcome in revision total knee arthroplasty: a meta-analysis.

PURPOSE: The fixation of revision total knee arthroplasties (rTKA) tends to be difficult, leading to a reduction in implant survival. One option for achieving a more stable anchorage is to use metaphyseal cones and sleeves. The objective of the present paper is to provide a current comparative meta-analysis on survival and clinical results of cones vs. sleeves, with a differentiation between the short- and long-term outcome. METHODS: A search of the literature was conducted systematically to include original papers from 2010 to June 2021. The following parameters were taken into account: revision for aseptic loosening, revision for any reason, periprosthetic joint infections (PJI), KSS as well as KSFS. Studies with a mean follow-up of at least 60 months were defined to be long-term follow-up studies (LT). All other studies were included in the short-term (ST) study analysis. A pooled incidence was used as a summary statistic using a random intercept logistic regression model. RESULTS: The present meta-analysis included 43 publications with 3008 rTKA. Of these, 23 publications with 1911 cases were allocated to the sleeve group (SG) and 20 papers with 1097 cases to the cone group (CG). CG showed overall numerically higher complication rates in short- and long-term follow-up, compared with SG. Aseptic loosening occurred at a rate of 0.4% in SG (LT) and 4.1% in CG (LT) (p = 0.09). Periprosthetic joint infection (PJI) was more frequent in the cone group (7% in ST and 11.7% in LT) than in the sleeve group (3.4% in ST and 4.9% in LT, p = 0.02 both). The total revision rate was 5.5% in SG (LT) and 14.4% in CG (LT) (p = 0.12). The clinical scores were also comparable between the two groups. Hinged prothesis were used more frequent in the cone group (ST p < 0.001; LT p = 0.10), whereas CC type protheses were used more frequently in the sleeve group (ST p < 0.001; LT p < 0.11). CONCLUSIONS: This meta-analysis takes into account the longest follow-up periods covered to date. Both cones and sleeves represent a reliable fixation method in the case of severe bone loss in rTKA, although the higher rate of PJI after cone fixation remains a source of concern. A metaphyseal fixation of hinged implants should be taken into account. LEVEL OF EVIDENCE: II (meta-analysis).

Modular Augmentation in Varus-Valgus-Constrained Knee Arthroplasty-Do We Need Sleeves to Avoid Femoral Loosening After Excessive Distal Augmentation?

BACKGROUND: In revision total knee arthroplasty, zonal fixation methods with a combination of augments, press-fit stems, and sleeves are popular. We hypothesized that high distal femoral augmentation with diaphyseal press-fit stems leads to an increased rate of early aseptic loosening and that femoral metaphyseal sleeves improve implant survival. Therefore, we retrospectively investigated implant survival in relation to augment heights and sleeves. METHODS: A total of 136 patients with mean clinical follow-up of 50 months (range, 28-85) who underwent modular total knee arthroplasty and revision total knee arthroplasty with semiconstrained implants between January 2012 and July 2018 were retrospectively evaluated. Implant survival with 4, 8, and 12 mm distal femoral augments was compared to no distal augmentation. Subsequently, a subgroup analysis was performed for femoral sleeve implantation. RESULTS: We observed an implant survival rate of 97.0%, 87.5%, and 69.2% for 4, 8, and 12 mm distal femoral augmentation, respectively (P = .73; P = .19; P = .008). The implant survival rate with femoral sleeves was 95.8% for the 8 mm augments and 85.7% for the 12 mm augments (P = .42; P = .96). Without femoral sleeves, the implant survival rate was 78.3% with the 8 mm augments and 50.0% with the 12 mm augments (P = .02; P < .001). CONCLUSION: Higher rates of aseptic femoral loosening were identified for distal femoral augmentation of 8 mm or more without metaphyseal sleeve fixation in semiconstrained implants. Thus, in cases with femoral metaphyseal bone damage requiring high distal femoral augmentation, metaphyseal sleeves should be used to avoid early aseptic femoral loosening.

Intermediate-Term Survivorship of Metaphyseal Cones and Sleeves in Revision Total Knee Arthroplasty.

BACKGROUND: Both cones or sleeves have been developed to address metaphyseal bone loss in revision total knee arthroplasty (TKA), but few studies have directly compared the outcomes. The purpose of this study was to compare the survivorship and aseptic revision rates between metaphyseal cones and sleeves at intermediate follow-up. METHODS: We reviewed a consecutive series of 1,172 revision TKA patients between 2009 and 2018 with a minimum two-year follow-up on all patients. We compared demographics, surgical indication, stem fixation, constraint, rates of rerevision, and Short-Form-12 scores between patients with cones and sleeves. A multivariate analysis was performed to identify the effect of cones and sleeves on aseptic rerevision. Kaplan-Meier curves were generated to compare aseptic survivorship of cones and sleeves. RESULTS: There were 194 tibial cones (17%), 107 tibial sleeves (9%), 31 femoral cones (3%), and 135 femoral sleeves (12%) with a mean follow-up of 6.5 years (range: 2-12 years). There was no difference in demographics, indication, stem fixation, or constraint (P > .05). Although overall aseptic failure rates may be lower for tibial sleeves, there were no significant differences in survivorship over a one-year, two-year, and five-year follow-up when both tibial and femoral sleeves were directly compared to cones. CONCLUSION: Both tibial and femoral sleeves and cones perform well at an intermediate-term follow-up. Further investigation of these two are required to better understand their survivorship relative to each other.

Revision Total Knee Arthroplasty With a Rotating-Hinge Prosthesis Mated to a Well-Fixed Femoral Sleeve.

BACKGROUND: Some knee systems have the unique capability to mate a new hinged femoral component to a well-fixed metaphyseal sleeve from a prior revision. We compared survivorship, radiographs, and clinical outcomes of a rotating-hinge total knee arthroplasty mated to a new metaphyseal sleeve vs a well-fixed sleeve. METHODS: Sixty patients with an S-ROM Noiles (DePuy Synthes, Warsaw, IN) rotating-hinge total knee arthroplasty implanted from 1998 to 2019 were retrospectively reviewed. Nine patients (15%) had the femoral component mated to a well-fixed sleeve and 51 patients (85%) had a new sleeve. Mean age was 68 years, 68% were female, and mean body mass index was 33 kg/m2. The incidences of re-revision and reoperation were calculated, Knee Society Scores were measured, and radiographs were reviewed. Mean follow-up was 5 years. RESULTS: There were 2 re-revisions (22%) in patients with a well-fixed sleeve: 1 for infection and 1 for aseptic loosening of the femur and tibia. There were no unique failures including the taper junction. Nine patients (18%) with a new sleeve were re-revised: 7 for infection and 2 for tibial aseptic loosening. The mean Knee Society Score for all patients improved from 39 to 73. Radiographically, all components were well fixed except for one loose femur in a patient with a new sleeve. CONCLUSION: Mating an S-ROM femur to a well-fixed sleeve from a prior revision is a safe, simple, and durable option in the short term that prevents morbidity associated with removal of a well-fixed sleeve. No new modes of failure were observed. LEVEL OF EVIDENCE: IV (retrospective), Therapeutic.

Survivorship of Metaphyseal Cones and Sleeves in Revision Total Knee Arthroplasty.

BACKGROUND: Bone loss remains an anticipated challenge in revision total knee arthroplasty (rTKA). Recent efforts to enhance rTKA fixation and stability have focused on metaphyseal implants, namely cones and sleeves. We sought to compare cone and sleeve implant survivorship in rTKA. METHODS: One hundred eighty patients who underwent rTKA with metaphyseal implants from 2005 to 2018 were retrospectively reviewed. A total of 83 cones (22 femoral, 62 tibial) and 121 sleeves (58 femoral, 63 tibial) were identified. The mean age at the time of surgery was 72 years (range 43-97). Intraoperative Anderson Orthopaedic Research Institute bone loss classifications included the following: type 2A (25), type 2B (98), and type 3 (81). Mean follow-up was 41 months. RESULTS: Revision-free survival for cones was 91.3% vs 92.2% for sleeves (P = .29). Twelve knees (4 cones, 8 sleeves) underwent irrigation, debridement, and polyethylene exchange with metaphyseal implant retention for acute postoperative periprosthetic joint infection (PJI). Development of chronic PJI warranted removal of 7 cones (8.4%), 6 of which were initially placed as part of a 2-stage revision TKA. Eight sleeves (6.6%) were removed for PJI, with all initially placed during a second stage reimplantation. In the absence of infection, survival was 100% and 99.1% for cones and sleeves, respectively. One sleeve was revised for periprosthetic fracture. CONCLUSION: Metaphyseal cones and sleeves offer equally durable survivorship in revision TKA. PJI was the most common mode of implant failure in this series. Importantly, no cases of cone or sleeve aseptic loosening were observed.

Smart-Sleeve: A Wearable Textile Pressure Sensor Array for Human Activity Recognition.

Human activity recognition is becoming increasingly important. As contact with oneself and the environment accompanies almost all human activities, a Smart-Sleeve, made of soft and stretchable textile pressure sensor matrix, is proposed to sense human contact with the surroundings and identify performed activities in this work. Additionally, a dataset including 18 activities, performed by 14 subjects in 10 repetitions, is generated. The Smart-Sleeve is evaluated over six classical machine learning classifiers (support vector machine, k-nearest neighbor, logistic regression, random forest, decision tree and naive Bayes) and a convolutional neural network model. For classical machine learning, a new normalization approach is proposed to overcome signal differences caused by different body sizes and statistical, geometric, and symmetry features are used. All classification techniques are compared in terms of classification accuracy, precision, recall, and F-measure. Average accuracies of 82.02% (support vector machine) and 82.30% (convolutional neural network) can be achieved in 10-fold cross-validation, and 72.66% (support vector machine) and 74.84% (convolutional neural network) in leave-one-subject-out validation, which shows that the Smart-Sleeve and the proposed data processing method are suitable for human activity recognition.

The susceptibility of the rat pulmonary and caval vein myocardium to the catecholamine-induced ectopy changes oppositely in postnatal development.

KEY POINTS: The developmental changes of the caval (SVC) and pulmonary vein (PV) myocardium electrophysiology are traced throughout postnatal ontogenesis. The myocardium in SVC as well as in PV demonstrate age-dependent differences in the ability to maintain resting membrane potential, to manifest automaticity in a form of ectopic action potentials in basal condition and in responses to the adrenergic stimulation. Electrophysiological characteristics of two distinct types of thoracic vein myocardium change in an opposite manner during early postnatal ontogenesis with increased proarrhythmicity of pulmonary and decreased automaticity in caval veins. Predisposition of PV cardiac tissue to proarrhythmycity develops during ontogenesis in time correlation with the establishment of sympathetic innervation of the tissue. The electrophysiological properties of caval vein cardiac tissue shift from a pacemaker-like phenotype to atrial phenotype in accompaniment with sympathetic nerve growth and adrenergic receptor expression changes. ABSTRACT: The thoracic vein myocardium is considered as a main source for atrial fibrillation initiation due to its high susceptibility to ectopic activity. The mechanism by which and when pulmonary (PV) and superior vena cava (SVC) became proarrhythmic during postnatal ontogenesis is still unknown. In this study, we traced postnatal changes of electrophysiology in a correlation with the sympathetic innervation and adrenergic receptor distribution to reveal developmental differences in proarrhythmicity occurrence in PV and SVC myocardium. A standard microelectrode technique was used to assess the changes in ability to maintain resting membrane potential (RMP), generate spontaneous action potentials (SAP) and adrenergically induced ectopy in multicellular SVC and PV preparations of rats of different postnatal ages. Immunofluorescence imaging was used to trace postnatal changes in sympathetic innervation, ß1- and α1A-adrenergic receptor (AR) distribution. We revealed that the ability to generate SAP and susceptibility to adrenergic stimulation changes during postnatal ontogenesis in an opposite manner in PV and SVC myocardium. While SAP occurrence decreases with age in SVC myocardium, it significantly increases in PV cardiac tissue. PV myocardium starts to demonstrate RMP instability and proarrhythmic activity from the 14th day of postnatal life which correlates with the appearance of the sympathetic innervation of the thoracic veins. In addition, postnatal attenuation of SVC myocardium automaticity occurs concomitantly with sympathetic innervation establishment and increase in ß1-ARs, but not α1A-AR levels. Our results support the contention that SVC and PV myocardium electrophysiology change during postnatal development, resulting in higher PV proarrhythmicity in adults.

Tibial tray cementation is not necessary for knee revision with titanium metaphyseal sleeves: a mid-term prospective study in AORI 2B defects.

PURPOSE: Metaphyseal fixation with porous titanium sleeves in revision knee surgery provides mechanical support to the implant, promotes biological fixation, and has shown satisfactory short- and mid-term results. Cement is commonly used to fix the tibial tray to the epiphyseal area. The objective of this study is to determine whether cement should be used to achieve fixation of the tibial tray with the hypothesis that metaphyseal sleeves would provide enough axial and rotational stability making cementation unnecessary. MATERIAL AND METHODS: Prospective study of 60 patients undergoing knee replacement surgery with metaphyseal sleeves in type 2B defects in femur and tibia. Patients were divided into two groups according to the use of cement on the tibial component. Analysis included the American Knee Society Score (KSS) knee and functional scales, the Western Ontario and McMaster Universities (WOMAC) index, the Short Form 12 (SF-12) health survey, and radiographic assessment with a maximum follow-up of 5 years. RESULTS: No statistically significant differences were found between the two groups in any of the parameters assessed. CONCLUSION: Metaphyseal sleeves showed a 100% survivorship at five years of followup. There were no differences in clinical and radiographic outcomes at five years of follow-up depending on whether or not cement was used for tibial platform fixation. Cementation of the tibial tray would therefore not be required to achieve satisfactory mid-term results. LEVEL OF EVIDENCE: Level II: prospective cohort study. Therapeutic.

Fast FMCW Terahertz Imaging for In-Process Defect Detection in Press Sleeves for the Paper Industry and Image Evaluation with a Machine Learning Approach.

We present a rotational terahertz imaging system for inline nondestructive testing (NDT) of press sleeves for the paper industry during fabrication. Press sleeves often consist of polyurethane (PU) which is deposited by rotational molding on metal barrels and its outer surface mechanically processed in several milling steps afterwards. Due to a stabilizing polyester fiber mesh inlay, small defects can form on the sleeve's backside already during the initial molding, however, they cannot be visually inspected until the whole production processes is completed. We have developed a fast-scanning frequenc-modulated continuous wave (FMCW) terahertz imaging system, which can be integrated into the manufacturing process to yield high resolution images of the press sleeves and therefore can help to visualize hidden structural defects at an early stage of fabrication. This can save valuable time and resources during the production process. Our terahertz system can record images at 0.3 and 0.5 THz and we achieve data acquisition rates of at least 20 kHz, exploiting the fast rotational speed of the barrels during production to yield sub-millimeter image resolution. The potential of automated defect recognition by a simple machine learning approach for anomaly detection is also demonstrated and discussed.

Morphometric characteristics of myocardial sleeves of the pulmonary veins.

BACKGROUND: The pulmonary veins are covered by a myocardial layer, which is often an electrical substrate for atrial fibrillation. The aim of this study was to study the morphologic characteristics of the myocardial sleeves of pulmonary veins by examining a large group of freshly autopsied human material. METHODS AND RESULTS: The study macroscopically examined a total of 498 pulmonary veins draining the left atrium (120 unpreserved human hearts). In 75.0% of specimens, a classical pulmonary venous pattern was observed. The remainder of specimens either had an additional middle right pulmonary vein (20.0% of cases) or a common left pulmonary vein (5.0% of cases). Among all the veins seen in the classical pulmonary venous drainage type, the left superior pulmonary vein had the longest myocardial sleeves (9.4 ± 4.6 mm; coverage = 60.1 ± 19.4%), followed by the left inferior pulmonary vein (6.6 ± 3.5 mm; coverage = 47.6 ± 18.3%), the right superior pulmonary vein (6.0 ± 2.7 mm; coverage = 50.5 ± 13.9%) and then the right inferior pulmonary vein (5.0 ± 2.8 mm; coverage = 45.6 ± 16.2%; analysis of variance p < .001). In hearts with an additional right pulmonary vein, this vessel had the shortest myocardial sleeves (2.7 ± 1.1 mm; coverage = 36.0 ± 11.6%). In hearts with a common left pulmonary vein, the myocardial sleeves had the longest course for the common vein (13.7 ± 4.4 mm; coverage = 79.7 ± 4.9%). CONCLUSIONS: Myocardial sleeves of the pulmonary veins were seen in each examined specimen, however, their length varied significantly. In hearts with a classical venous drainage pattern, the left superior pulmonary vein had the longest sleeves. When present, an additional middle right pulmonary vein had the shortest myocardial sleeves, while the left common pulmonary vein had the longest sleeves.

Excellent mid-term osseointegration and implant survival using metaphyseal sleeves in revision total knee arthroplasty.

PURPOSE: Metaphyseal fixation in revision total knee arthroplasty (RTKA) is a very promising treatment option for extended bone defects. Currently published mid-term results remain limited. The purpose was to analyse the implant durability, the clinical and the radiological mid-term results in RTKA when using metaphyseal sleeves. METHODS: Clinical and radiological follow-up examinations were performed in 92 patients (93 knees) with RTKA using hybrid fixation technique (cementless sleeves and stem). Radiographic measurements regarding osseointegration at the bone-sleeve interface were performed and the range of motion (ROM), a subjective satisfaction score (SSS), the American Knee Society Score (KSS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) as well as the SF-36 Health survey were examined. Bone defects were analysed using the Anderson Orthopaedic Research Institute (AORI) classification. RESULTS: No knee had to be revised due to aseptic loosening at the time of the follow-up (mean 6.3 years ± 2.3, minimum 2 years). Satisfactory radiographic osseointegration at the sleeve/bone interface was detected in 96.1% of cases. 17 knees (18.2%) had to be re-revised, 15 of them due to a recurrent infection and 2 due to aseptic reasons (mediolateral instability and a periprosthetic fracture). The median of the ROM (96°), SSS (8), KSS (87), WOMAC (9), SF-36 MCS (55) and SF-36 PCS (38) showed very satisfying results. CONCLUSION: No case of aseptic loosening was found in this large series of RTKA with extended bone defects using metaphyseal sleeve fixation. In this large retrospective series, it has been shown that this technique is an excellent treatment option for extended bone defects in RTKA surgery. LEVEL OF EVIDENCE: Retrospective cohort study, level III.

Metaphyseal Sleeves in Revision Total Knee Arthroplasty Provide Reliable Fixation and Excellent Medium to Long-Term Implant Survivorship.

BACKGROUND: Addressing bone loss and securing implant fixation can be challenging in revision total knee arthroplasty (TKA). We present the results of a large series of revision TKAs using a metaphyseal sleeve. METHODS: We retrospectively analyzed 319 revision TKAs with the use of a metaphyseal sleeve that had been followed up for at least 2 years, using a prospectively collected database. The mean follow-up was 91 months, and 73 patients were followed up for more than 10 years. RESULTS: Implant survivorship was 99.1% at 3 years, 98.7% at 5 years, and 97.8% at 10 years. No metaphyseal sleeve was revised for aseptic loosening. Final radiographic review showed that there were radiolucent lines present in 2.8% of tibial sleeves and 2.7% of femoral sleeves; none of these had progressed and none were revised. About 3.7% of tibial sleeves subsided more than 1 mm compared with the immediate postoperative X-ray but all stabilized and none were revised. CONCLUSION: Use of a metaphyseal sleeve in revision TKA is associated with excellent survivorship and radiographic outcome in the medium to long term.

Management of the bone loss by metaphyseal sleeves in primary and revision knee arthroplasty: clinical experience and outcome after forty three cases.

AIM OF THE STUDY: Management of metaphyseal bone loss in complex primary and revision TKA is a challenge for surgeons. Out of various types of bony defects, large metaphyseal bone loss (AORI types IIB and III) requires special augments in the form of cones or sleeves. The aim of this study is to assess the reliability of metaphyseal sleeves, in dealing with massive bone defects to provide stability for immediate weight bearing and also to check short to mid-term survivorship of metaphyseal sleeves in Asian population by assessing various parameters and complications. METHODS: This is a retrospective study that includes 36 patients (43 knees), operated from 2011 to 2019. Patients with AORI type IIB (large metaphyseal bone defect) and AORI type III (metaphyseal defect with compromised collateral ligaments) were included. We included both the primary and revision knee arthroplasties in our study. Our interest in this study was to look for incidence of intra-operative iatrogenic fracture on the one hand, and post-operative complications in the form of peri-prosthetic joint infection and aseptic loosening on the other hand. Knee Society Score (KSS) was used to assess improvement in patient's clinical outcome. SPSS version 23 was used to process data. RESULTS: The average age of patients in our study was 59.4 (SD 9.78) years. Male to female ratio was 21:15. The average follow-up was 5.42 (SD 2.24) years with the longest follow up of nine years. Metaphyseal sleeves were used in 12 primary TKA and 31 revision TKA. During surgery, iatrogenic fracture of tibial condyle was encountered in three patients (6.9%), all were managed without any intervention and union was achieved in all cases. There was not a single case with aseptic loosening as per radiological criteria in our study. Peri-prosthetic joint infection (PJI) was encountered in a single case (2.3%). Pre-op Knee Society Score (KSS) was 36.21 (SD 7.43) where as it improved to 92.00 (SD 5.66), six months after surgery. Also the range of flexion was increased from 76.83o (SD 14.07o) to 122.91o (SD 4.84o). CONCLUSION: In our study, metaphyseal sleeves showed excellent short to mid-term survivorship in AORI types IIB and III boneloss in Asian population. These results are comparable to various studies conducted on North American and European population. Metaphyseal sleeve is a reliable tool in the armamentarium of the arthroplasty surgeon. It is user friendly implant and provides immediate stability to allow full weight-bearing mobilization.

Unique, Cost-effective and Retentive Removable Prosthesis to Rehabilitate Long Span Kennedy's Class I Edentulism with Custom Attachment System: A Case Report.

AIM: This case report describes about a distinctive custom-made attachment on the abutment teeth to improve the retention and stability of the removable partial denture (RPD). It also throws light on the cost-effective method for altering the abutment teeth with the aid of the crowns and custom-made attachments. BACKGROUND: Achieving retention in Kennedy's class I bilateral edentulism usually affects the abutment teeth's periodontal health and eventually the retention is compromised. Distal extension edentulism also affects patient's masticatory efficiency. The rehabilitation of a patient with the long span Kennedy's class I condition complicates the problem because of the unavailability of enough abutments to support the prosthesis. Conventional removable prosthesis with clasps and cantilever fixed partial prosthesis are not advisable in this situation for the same reason. CASE DESCRIPTION: A case with Kennedy's class I modification 1 partially edentulous arch with 1st and 2nd molars missing along with central incisors was rehabilitated with an inexpensive custom attachment using die pin and sleeve for giving a fixed prosthesis on abutment teeth and removable prosthesis with missing teeth. CONCLUSION: This technique has advantages of retention better than conventional RPDs, protection of abutment health by restoring it with crown, easy to place and remove and very cost-effective. CLINICAL SIGNIFICANCE: The entire technique demands less skill compared to semi precision and precision attachments.

Rat caval vein myocardium undergoes changes in conduction characteristics during postnatal ontogenesis.

The electrophysiological properties of the superior vena cava (SVC) myocardium, which is considered a minor source of atrial arrhythmias, were studied in this study during postnatal development. Conduction properties were investigated in spontaneously active and electrically paced SVC preparations obtained from 7-60-day-old male Wistar rats using optical mapping and microelectrode techniques. The presence of high-conductance connexin 43 (Cx43) was evaluated in SVC cross-sections using immunofluorescence. It was found that SVC myocardium is excitable, electrically coupled with the atrial tissue, and conducts excitation waves at all stages of postnatal development. However, the conduction velocity (CV) of excitation and action potential (AP) upstroke velocity in SVC were significantly lower in neonatal than in adult animals and increased with postnatal maturation. Connexins Cx43 were identified in both neonatal and adult rat SVC myocardium; however, the abundance of Cx43 was significantly less in neonates. The gap junction uncoupler octanol affected conduction more profound in the neonatal than in adult SVC. We demonstrated for the first time that the conduction characteristics of SVC myocardium change from a slow-conduction (nodal) to a high-conduction (working) phenotype during postnatal ontogenesis. An age-related CV increase may occur due to changes of AP characteristics, electrical coupling, and Cx43 presence in SVC cardiomyocyte membranes. Observed changes may contribute to the low proarrhythmicity of adult caval vein cardiac tissue, while pre- or postnatal developmental abnormalities that delay the establishment of the working conduction phenotype may facilitate SVC proarrhythmia.