One-stage Procedure Research Articles

A modified one stage multiple comparison procedure of exponential location parameters with the control under heteroscedasticity

In this paper, we present a modified one-stage multiple comparison procedure for exponential location parameters with the control under heteroscedasticity including one-sided and two-sided confidence intervals to improve the coverage probability and average confidence length than the old one. These intervals can be used to identify a subset which includes all no-worse-than-the-control treatments in an experimental design and to identify better-than-the-control, worse-than-the- control and not-much-different-from-the-control products in agriculture, stock market, pharmaceutical industries in terms of the minimum guarantee lifetimes. A simulation comparison is done for this modified procedure with the old one in terms of the confidence length and coverage probability. One example is given to demonstrate the proposed modified procedure.

Bone Ring Autogenous Graft and Immediate Implant Reconstruction in Atrophic Posterior Mandibular Area

Purpose: to evaluate clinical and radiographic outcome of bone ring grafting technique with immediate implant placement in fresh extraction socket in mandibular posterior area. Patients and methods: Clinical study was conducted on six patients, suffer from deficiency in vertical height at posterior mandibular area. Extraction and immediate implant reconstruction with symphyseal bone grafting in one-stage procedure. All steps of harvesting by trephine bur, implant osteotomy and placement within the socket were guided by computerized surgical stent for donor and recipient sites. Platelet Rich Fibrin (PRF) membrane was prepared to cover the implant at suture line. Patients were followed up clinically and radiographically by Cone Beam Computed Tomography (CBCT) at immediate,3 and 6 months postoperatively to evaluate the implant site and vertical bone height changes. Results: One successful case out of six showed excellent soft tissue healing with implant stability. Clinically one case showed sever infection at 2 weeks postoperatively with looseness of implant. Dehiscence and pain were found in 83.3% of the cases. Four cases had mild pain and one case suffered from severe pain, edema was mild in the majority of patients, numbness was found in 4 cases with 66.7%. CBCT results showed significant decrease in 3D dimensions of vertical bone height from immediate postoperative to 6 months with percentage of resorption (Buccally37.49±12.14, Lingually36.12±12.04, Mesially 39.55±15.05 and Distally10.92±0.76). Conclusion: From our study, Bone ring augmentation technique for fresh defective sockets with immediate implants at posterior mandibular area achieved low success rate, long procedure time and donor site morbidity.

A systematic review and meta-analysis on the management of concomitant abdominal aortic aneurysms and renal tumours.

The treatment of concomitant abdominal aortic aneurysms and renal tumours is controversial. The aim of this study was to ascertain which of the following three strategies, one-stage open aneurysm repair and nephrectomy, two-stage open aneurysm repair and nephrectomy or two-stage endovascular aneurysm repair and nephrectomy, is the best approach. systematic review and meta-analysis of articles published between January 1992 and April 2021 describing the treatment of concomitant abdominal aortic aneurysms and renal tumours. A total of 1168 records were identified. After the selection process, 12 studies with data on 89 patients were included. Sixty-two patients underwent one-stage open procedures, 18 patients underwent two-stage open procedures and nine underwent two-stage endovascular procedures. The overall postoperative mortality was 0.82% (95% CI, 0.00-4.61). The postoperative mortality for one-stage open procedures was 3.09% (95% CI, 0.00-10.11). No deaths occurred in the postoperative period open two-stage procedures or two-stage endovascular procedures. The weighted postoperative morbidity for all procedures was 23.86% (95% CI, 12.64-35.08) and for open one-stage procedures was 37.40% (95% CI, 14.33-60.47). Data concerning postoperative complications of two-stage open procedures were extractable from only one patient in whom no complications were reported. Two postoperative complications were reported after two-stage endovascular procedures from a total of six patients with extractable postoperative data. We were unable to perform meta-analysis on long-term outcomes as the data were reported non-uniformly. There is currently no evidence to suggest that any procedure is associated with better outcomes. However, a one-stage open approach was the most commonly used option, favoured as it avoids delaying treatment of either of the conditions. Two-stage open procedures were preferred in cases where the surgical risk of a one-stage procedure was higher than the potential benefit. For such cases, two-stage endovascular repair is becoming more popular as a less invasive approach.

Long-Term fate of the upper urinary tract and ITS association with continence in exstrophy patients

Scarce data is available in literature about the upper urinary tract outcomes of patients with Exstrophy-Epispadias Complex (EEC). After bladder closure during childhood, EEC bladders can become hostile to the upper tracts after bladder by exposing them to high pressures, leading to hydronephrosis (HN) and kidney damage. Similarly, vesicoureteral reflux (VUR) may be present and increase the likelihood for pyelonephritis. We sought to assess long-term upper urinary tract outcomes by evaluating renal function, HN and VUR; and to assess if upper urinary tract outcomes are associated with continence status. A retrospective review of EEC patients having ≥1 surger(y) (ies) at our institution from 1990 until 2019 was performed. Renal function was assessed by evaluating last available estimated glomerular filtration rate (eGFR) and creatinine values. HN was assessed on ultrasound and classified according to the SFU-classification. Patients with recurrent febrile urinary tract infections (UTI) or pyelonephritis underwent a voiding-cystourethrogram (VCUG) assessing VUR, graded following the 'International system of radiographic grading of VUR'. Descriptive and comparative statistical analysis were performed to assess if upper tract outcomes are associated with continence status. Forty-eight patients (75% male) had a median (IQR) follow-up of 18 (10-21) years. The table shows upper tract outcomes for the entire group and stratified by continence status. The median creatinine was 0.6 (0.2-0.9) mg/dL and median eGFR was 108 (72-160) mL/min/1.73m [2]. In two patients (4.2%), HN (SFU-grade 2) was detected. Thirty-six patients (75%) underwent VCUG, revealing high-grade VUR (stage IV-V) in 8 patients (17%) and low-grade VUR (stage I-III) in 7 patients (15%). Continence was associated with a higher need for VCUG (p=0.02) and a higher presence of VUR (p=0.03). Renal function in EEC patients and non-EEC patients is comparable when age matched. Only 6% had low-grade HN which was asymptomatic. 17% had high-grade VUR, which is little compared to literature (40-70%). However, results in literature are described in patients with a 'one-stage' bladder closure, whereas some of our patients had a 'two-stage' procedure. A one-stage procedure creates higher bladder pressures resulting in higher VUR-rates. Statistical analysis has showed that continence is associated with a higher prevalence of recurrent febrile UTI's or pyelonephritis and of VUR. No statistically differences were found between continent and incontinent patients concerning creatinine and eGFR value (p=0.52 and p=0.29), nor in the prevalence of hydronephrosis (p=0.36). However, results of this study suggest that continent patients may portend a higher risk of upper tract deterioration with recurrent febrile UTI's and pyelonephritis due to VUR. Close monitoring of the upper tract status is therefore as important as focus on continence. Large-scale prospective studies defining renal function as well as pyelonephritis rates are needed to optimize the management of the upper tracts in EEC patients.

Short-Term Follow-Up of the PROSTALAC Implant for Primary Total Hip Arthroplasty in Patients with an Infected Native/Total Hip

AbstractInfection after a total hip replacement (THR) is a significant complication for patients and is costly for health services. The two-stage Prosthesis with Antibiotic Loaded Acrylic (PROSTALAC) procedure has been the gold standard treatment for managing THR infections. The aim of this study is to evaluate using a one-stage PROSTALAC procedure as an alternative for patients who would otherwise not be able to undergo THR surgery due to a previous hip infection.We evaluated nine cases where the PROSTALAC implant was used in the native hip. The reasons for surgery, clinical results, and complications were reviewed. An Australian Orthopaedic Association National Joint Replacement Registry data report verified that no patients were revised outside of our local center.All patients reported symptomatic relief and satisfactory function, one patient had a peri-prosthetic fracture after experiencing a fall, and one patient underwent surgery for loosening of the joint. No cases were revised to another implant or had further infection. Minimum follow-up was 2 years.Our results suggest that this implant is useful in patients with osteoarthritis of the hip with a history of previous infection or chronic infection of the native hip.

Skin substitutes with noncultured autologous skin cell suspension heal porcine full-thickness wounds in a one-stage procedure.

Clinical application of skin substitute is typically a two‐stage procedure with application of skin substitute matrix to the wound followed by engraftment of a split‐thickness skin graft (STSG). This two‐stage procedure requires multiple interventions, increasing the time until the wound is epithelialised. In this study, the feasibility of a one‐stage procedure by combining bioengineered collagen‐chondroitin‐6‐sulfate (DS1) or decellularised fetal bovine skin substitute (DS2) with autologous skin cell suspension (ASCS) in a porcine full‐thickness wound healing model was evaluated. Twelve full‐thickness excisional wounds on the backs of pigs received one of six different treatments: empty; ASCS; DS1 with or without ASCS; DS2 with or without ASCS. The ASCS was prepared using a point‐of‐care device and was seeded onto the bottom side of DS1, DS2, and empty wounds at 80 000 cells/cm2. Wound measurements and photographs were taken on days 0, 9, 14, 21, 28, 35, and 42 post‐wounding. Histological analysis was performed on samples obtained on days 9, 14, 28, and 42. Wounds in the empty group or with ASCS alone showed increased wound contraction, fibrosis, and myofibroblast density compared with other treatment groups. The addition of ASCS to DS1 or DS2 resulted in a marked increase in re‐epithelialisation of wounds at 14 days, from 15 ± 11% to 71 ± 20% (DS1 vs DS1 + ASCS) or 28 ± 14% to 77 ± 26 (DS2 vs DS2 + ASCS) despite different mechanisms of tissue regeneration employed by the DS used. These results suggest that this approach may be a viable one‐stage treatment in clinical practice.

Is the Two-Stage Construction Approach Better for Maturation and Long-term Patency of the Transposed Brachiobasilic Arteriovenous Fistulas?

The transposed brachiobasilic arteriovenous fistula is often constructed by employing a two-stage procedure for better maturation and long-term patency, but its validity on overall outcomes remains controversial. A single-center's experience is presented herein, comparing one- and two-stage approaches on 229 consecutive first-time arteriovenous access constructed in the upper arm with a loop configuration and an obtuse anastomosis angle that provide favorable flow dynamics. The one- and two-year patency rates were equivalent between the two approaches, but the fistula rate was greater and the maturation time was shorter with the one-stage procedure.

Clinical Outcome of Dental Implants after Maxillary Sinus Augmentation with and without Bone Grafting: A Retrospective Evaluation.

(1) Background: The purpose of the present study was to retrospectively evaluate and compare the outcome of two sinus augmentation grafting protocols using a xenograft or blood clot alone over a 72-month follow-up. (2) Methods: Patients who received simultaneous lateral sinus floor augmentation and implant placement were included. Subjects were divided into two groups according to the grafting material, namely xenograft or blood clot, and into sub-groups based on the residual alveolar bone height (RABH) below the maxillary sinus, namely 4 to 6 mm or >6 mm. Kaplan–Meier survival estimates were calculated for each material group and for each sub-group at 1, 3, and 6 years. (3) Results: In total, 289 implants inserted in 136 patients with a one-stage procedure were considered. A total of 35 failures were registered. Overall survival rates were 94.2% for xenograft and 85.9% for blood clot alone at 1 year, 91.1% and 81.6% at 3 years, and 91.1% and 78.7% at 6 years. (4) Conclusions: In patients with 4–6 mm RABH, graftless interventions exploiting blood clot alone were not as successful as those using xenograft. When the RABH is low, sinus floor augmentation associated with grafting materials should be preferred whenever possible.

Predictive Value of CT Enterography Index for Postoperative Intra-abdominal Septic Complications in Patients With Crohn's Disease: Implications for Surgical Decision-Making.

Postoperative intra-abdominal septic complications in patients with Crohn's disease undergoing intestinal resection and anastomosis are frequent and difficult to manage. This study sought to explore the value of preoperative CT enterography to predict intra-abdominal septic complications. This was a retrospective and prospective observational study. This study was conducted in a tertiary referral hospital. Patients with Crohn's disease undergoing primary intestinal resection were enrolled in our study. The CT enterography severity index was calculated and its ability to predict intra-abdominal septic complications evaluated by multivariate analyses. A prospective study was then performed to assess the reliability of this CT enterography index. The incidence of postoperative intra-abdominal septic complications in patients undergoing a 1-stage procedure was significantly higher than those undergoing a 2-stage procedure (3/103 vs 24/241; 2.9% vs 10.0%; p = 0.026). A multivariate analysis identified 5 CT enterography parameters, including mesenteric fibrofatty proliferation, intra-abdominal abscess or phlegmon, intestinal fistula, peritoneal effusion, and intestinal dilatation with stricture to be independent predictors of intra-abdominal septic complications (p < 0.001). A nomogram model based on these 5 parameters was constructed. A receiver operating characteristic analysis identified a CT enterography nomogram score cutoff of 175 as a predictor of intra-abdominal septic complications with a sensitivity of 83.3% and a specificity of 85.3%. In the prospective study, those patients with a CT enterography nomogram score >175 were assigned to the 2-stage group, which resulted in a similar intra-abdominal septic complication incidence in those undergoing intestinal resection with or without anastomosis (2/82 vs 2/34; p = 0.355). This study was limited by its single-center scope. Preoperative CT enterography findings may predict postoperative outcomes and help determine surgical approach in Crohn's disease. Patients with worse intra-abdominal findings confirmed by CT enterography may benefit from stoma creation after intestinal resection. See Video Abstract at http://links.lww.com/DCR/B588. ANTECEDENTES:Las complicaciones sépticas intra-abdominales postoperatorias en pacientes con enfermedad de Crohn sometidos a resección intestinal y anastomosis son frecuentes y difíciles de manejar.OBJETIVO:Este estudio buscó explorar el valor del índice enterográfico por tomografía computada en el pré-operatorio y así poder predecir futuras complicaciones sépticas intra-abdominales.DISEÑO:Estudio observacional retro-prospectivo.AJUSTE:Investigación realizada en un hospital de referencia terciaria.PACIENTES:Se incluyeron en nuestro estudio pacientes con enfermedad de Crohn sometidos a una resección intestinal primaria.PRINCIPALES MEDIDAS DE RESULTADO:Se calculó el índice de gravedad de la enterografía por tomografía axial computada y se evaluó su capacidad para predecir las complicaciones sépticas intra-abdominales mediante un análisis multivariado. Luego se realizó un estudio prospectivo para evaluar la confiabilidad del índice enterográfico por tomografía axial computada.RESULTADOS:La incidencia de complicaciones sépticas intra-abdominales postoperatorias en pacientes sometidos a un procedimiento de un solo tiempo fue significativamente mayor que aquellos sometidos a un procedimiento de dos tiempos (3/103 frente a 24/241; 2,9% frente a 10,0%; p = 0,026). El análisis multivariado identificó cinco parámetros enterográficos por tomografía axial computada, incluidos la proliferación fibrograsa mesentérica, el absceso o flegmón intra-abdominal, la fístula entérica, el derrame peritoneal y la dilatación intestinal debido a estenosis como predictores independientes de complicaciones sépticas intra-abdominales (p <0,001). Se construyó un modelo de Nomograma basado en estos cinco parámetros. Un análisis de las características operatorias del receptor identificó una puntuación de cohortes del nomograma de la enterografía por tomografía axial computada de 175 como predictor de complicaciones sépticas intra-abdominales con una sensibilidad del 83,3% y una especificidad del 85,3%. En el estudio prospectivo, los pacientes con puntuación de nomograma enterográfico por tomografía axial computada superior a 175 fueron asignados al grupo en dos tiempos, lo que resultó en una incidencia similar de complicaciones sépticas intra-abdominales en aquellos sometidos a resección intestinal con o sin anastomosis (2/82 vs. 2/34; p = 0,355).LIMITACIONES:Este estudio estuvo limitado por su alcance unicéntrico.CONCLUSIÓN:Los hallazgos enterográficos por tomografía axial computada pré-operatoria pueden predecir ciertos resultados postoperatorios y ayudar a determinar el abordaje quirúrgico en la enfermedad de Crohn. Los pacientes con peores hallazgos intra-abdominales confirmados por enterografía en la tomografía axial computada podrían beneficiarse de la creación de un estoma después de la resección intestinal. Consulte Video Resumen en http://links.lww.com/DCR/B588. (Traducción-Dr Xavier Delgadillo).

To Trial or Not to Trial Before Spinal Cord Stimulation for Chronic Neuropathic Pain: The Patients’ View From the TRIAL-STIM Randomized Controlled Trial

ObjectivesSpinal cord stimulation (SCS) is an established treatment of chronic neuropathic pain. Although a temporary SCS screening trial is widely used to determine suitability for a permanent implant, its evidence base is limited. The recent TRIAL-STIM study (a randomized controlled trial at three centers in the United Kingdom) found no evidence that an SCS screening trial strategy provides superior patient outcomes as compared with a no trial approach. As part of the TRIAL-STIM study, we undertook a nested qualitative study to ascertain patients’ preferences in relation to undergoing a screening trial or not. Materials and MethodsWe interviewed 31 patients sampled from all three centers and both study arms (screening trial/no trial) prior to SCS implantation, and 23 of these patients again following implantation (eight patients were lost to follow-up). Interviews were undertaken by telephone and audio-recorded, then transcripts were subject to thematic analysis. In addition, participants were asked to state their overall preference for a one-stage (no screening trial) versus two-stage (screening trial) implant procedure on a five-point Likert scale, before and after implantation. ResultsEmergent themes favoured the option for a one-stage SCS procedure. Themes identified include: saving time (off work, in hospital, attending appointments), avoiding the worry about having “loose wires” in the two-stage procedure, having only one period of recovery, and saving NHS resources. Participants’ rated preferences show similar support for a one-stage procedure without a screening trial. ConclusionsOur findings indicate an overwhelming preference among participants for a one-stage SCS procedure both before and after the implant, regardless of which procedure they had undergone. The qualitative study findings further support the TRIAL-STIM RCT results.

Immediate electrophysiological characteristics following modified thoracoscopic ablation via unilateral approach for non-valvular atrial fibrillation

Thoracoscopic ablation has emerged as an effective therapy for patients with long-standing persistent Atrial fibrillation (LsPAF). We aimed to investigate the immediate electrophysiological characteristics following modified ablation with 3 circular and 3 linear lesions in the thoracoscopic procedure via a unilateral approach. Between May 2015 and October 2018, 40 patients underwent the one-stage hybrid procedure for LsPAF. Isolation of the pulmonary veins (PV) and left atrium posterior wall (LAPW), excision of the left atrial appendage (LAA), and high-density endocardial mapping and individualized percutaneous catheter ablation for AF termination were performed. The modified thoracoscopic procedure may enable successful PV and LAPW isolation and LAA removal. Endocardial electrophysiological examination showed 6 out of 40 (15%) patients with a right PV gap, 3 (7.5%) patients with incomplete roof lesions, and 8 (20%) patients with incomplete Dallas lesions. A total of 44 driving areas were mapped and ablated. Thirty-five patients achieved procedural AF termination. After a mean follow-up period of 26months, the success rate of a single procedure was 85%. Cox regression analysis demonstrated that the failure of procedural AF termination may be a risk factor in atrial tachyarrhythmia recurrence. Endocardial electrophysiological examination is a necessary partner to thoracoscopic ablation. Our modified thoracoscopic ablation and driving areas-based ablation contribute to high rates of procedural AF termination, which may lead to reduced recurrence rate. The hybrid procedure may be an effective strategy for the management of LsPAF.

Estimation of the association parameters in hierarchically clustered survival data by nested Archimedean copula functions

Statisticians are frequently confronted with highly complex data such as clustered data, missing data or censored data. In this manuscript, we consider hierarchically clustered survival data. This type of data arises when a sample consists of clusters, and each cluster has several, correlated sub-clusters containing various, dependent survival times. Two approaches are commonly used to analysis such data and estimate the association between the survival times within a cluster and/or sub-cluster. The first approach is by using random effects in a frailty model while a second approach is by using copula models. Hereby we assume that the joint survival function is described by a copula function evaluated in the marginal survival functions of the different individuals within a cluster. In this manuscript, we introduce a copula model based on a nested Archimedean copula function for hierarchical survival data, where both the clusters and sub-clusters are allowed to be moderate to large and varying in size. We investigate one-stage, two-stage and three-stage parametric estimation procedures for the association parameters in this model. In a simulation study we check the finite sample properties of these estimators. Furthermore we illustrate the methods on a real life data-set on Chronic Granulomatous Disease.

A Successful Endovascular Technique for Complete False Lumen Thrombosis in Chronic Abdominal Aortic Dissection.

A 66-year-old man presented with an enlarging abdominal aorta false lumen, after type A aortic dissection repair. Residual entries were located at the left renal artery, abdominal aorta, and left external iliac artery. The patient underwent endovascular aortic repair with left renal artery stenting to close the entries. Completion aortography showed no false lumen flow without an endoleak, and contrast-enhanced computed tomography 1 month after the procedure demonstrated complete false lumen thrombosis. A total endovascular approach is possible for abdominal aneurysmal dilation in chronic aortic dissection when all entries can be closed using a one-stage procedure with stent grafts and/or branch stenting.

An open, randomised, multi-centre study, comparing straight and tapered apex implants design, in partially and totally edentulous maxillae

The design of the commercially available implant OsseoSpeed® (control) was changed to a tapered apex with a smaller apical diameter; OsseoSpeed® TX (test). Objective The present study evaluated the clinical outcome of marginal bone level as primary outcome, and cumulative implant survival rate, primary stability and condition of the peri-implant mucosa as secondary outcomes, one year after loading. Material and methods 92 subjects (150 implants, ten centres), with partially or totally edentate maxillae were randomized to receive either test or control implants. One to six implants were placed in each subject using a one-stage surgical procedure. Subjects received a permanent prosthesis 10–12 weeks after implant placement and were followed for one year Results 47 subjects in the test group received 82 implants and 45 subjects in the control group received 68 implants. Marginal bone level alterations from loading to 1-year follow-up was −0.02 × 0.41 mm (mean × SD) and −0.03 × 0.38 mm (mean × SD) for the test and the control group, respectively, indicating no difference between the groups. Non-inferiority was declared as confidence interval for the difference between control and test implants was no worse than 0.5 mm. The CSR was 98.8% in the test group and 100% in the control group, with no statistically significant difference between the groups. Conclusions Change of the apical design of a commercially available implant showed no significant effect on marginal bone level and CSR compared to the control implant. Missing data and many investigators may have influenced on the result. Trial registration number: NCT 01324778.

The Harvest of a Lateral Segment of Costal Cartilage for Treating Nasal Deformities.

Although costal cartilage has many uses and is a reliable source of cartilage for rhinoplasty procedures, donor-site complications may arise with conventional harvesting techniques. The present report reports a novel technique of harvesting costal cartilage using a specially designed scalpel and studies the use of the harvested cartilage in the reconstruction of secondary nasal deformities in patients with cleft lips. Ten patients (7 females and 3 males) with nasal deformities secondary to cleft lip underwent rhinoplasty using this new technique at the Department of Oral and Maxillofacial Surgery, Second Hospital of Hebei Medical University, China, between May 2011 and December 2013. Clinical outcomes were evaluated with a follow-up period of 6 to 30 months. The new technique successfully corrected primary nasal deformities, including flat nasal tip, short columella, flaring alae, and asymmetrical nostrils. Surgeons and patients assessed the outcome to be either good or satisfactory. Patients experienced transient discomfort at the wound site but there were no major complications (such as wound infection, dehiscence, exposure, graft extrusion, and pulmonary involvement). The novel technique can harvest a lateral segment of costal cartilage for use in the reconstruction of nasal deformities secondary to cleft lip in a one-stage procedure, with minimal donor-site morbidity.

One-stage versus two-stage revision of the infected knee arthroplasty - a randomized multicenter clinical trial study protocol

BackgroundA two-stage prosthesis exchange procedure has been the gold standard in surgical treatment of the chronically infected knee arthroplasty so far. This includes 2 surgeries/hospitalizations and an interim period of 2–3 months between surgeries with impaired health, functional status and quality of life of the patients. A one-stage exchange procedure holds many obvious advantages compared to the two-stage approach, but outcomes of a one-stage versus two-stage procedures have never been investigated in a randomized clinical trial. The purpose of this study is primarily to investigate time-adjusted differences in functional status of patients after one-stage versus two-stage revision. Secondary, to report time-adjusted differences in quality of life, complications (including re-revisions due to infection) and mortality.MethodsThis study is a pragmatic, multi-center, randomized, non-inferiority trial comparing one-stage versus two-stage revision of the infected knee arthroplasty. Seven Danish hospitals are currently participating in the study, but additional hospitals can enter the study if adhering to protocol. Ninety-six patients will be included prospectively. Follow-up will be with PROM-questionnaires and clinical controls up to 10 years. The patients who are not able to participate in the randomized trial are followed in a parallel cohort study.PROM’sOxford Knee Score and EQ5D + EQ5D VAS questionnaires are completed preoperatively and sent out to the study participants at 6 weeks, 3, 6, 9, 12, 18 and 24 months as well as 5 and 10 years postoperatively. In addition a tailor made cost questionnaire on the non-treating hospital resource use, community health and social service use, travel costs, time off work and informal care are sent out.DiscussionIf one of the two treatment alternatives is found superior in both domains of quality of life (both knee-specific and generic) and health economics, that treatment should be promoted. Other outcomes will open informed discussions about treatment strategies for periprosthetic knee infections.Trial registrationThe randomized trial is registered on ClinicalTrials.gov with ID NCT03435679, initial release date January 31, 2018 and the cohort study is registered with ID NCT04427943, submitted January 8, 2020 and posted June 11, 2020.

Sparse principal component regression via singular value decomposition approach

Principal component regression (PCR) is a two-stage procedure: the first stage performs principal component analysis (PCA) and the second stage builds a regression model whose explanatory variables are the principal components obtained in the first stage. Since PCA is performed using only explanatory variables, the principal components have no information about the response variable. To address this problem, we present a one-stage procedure for PCR based on a singular value decomposition approach. Our approach is based upon two loss functions, which are a regression loss and a PCA loss from the singular value decomposition, with sparse regularization. The proposed method enables us to obtain principal component loadings that include information about both explanatory variables and a response variable. An estimation algorithm is developed by using the alternating direction method of multipliers. We conduct numerical studies to show the effectiveness of the proposed method.

Analysis of clinical outcomes of one-staged hybrid procedure without thoracotomy for aorta lesion involving distal aortic arch.

This study aimed to evaluate the clinical outcomes of one-staged hybrid procedure for aortic lesions involving the distal aortic arch. We retrospectively studied 99 consecutive patients who underwent the hybrid procedure (thoracic endovascular aortic repair combined with supra-arch branch vessel bypass) in our center between April 2009 and January 2020 for lesions involving the distal aortic arch. Median age was 64.0 (57.0-69.0) years, and 83 (83.8%) patients were male. There were five deaths in the perioperative period (three due to cerebral infarction and two due to intimal rupture). During the median follow-up of 41.0 months, 20 patients died, three had endoleak, one had a newly formed intimal tear, and two had femoral artery pseudoaneurysm. The 5- and 10-year survival rates of the total population were 72.2% and 48.8%, respectively. Additionally, there was no difference in the 5-year survival rate among the four groups according to different pathologies (Type B aortic dissection, aortic ulcer, aortic aneurysm, aortic pseudoaneurysm: 74.7%, 78.2%, 61.1%, and 75.5%, respectively, p = .58). Furthermore, there was no difference in the 5- and 10-year survival rates between the two groups according to the different bypass methods (right axillary artery [RAA]-left axillary artery [LAA] vs. RAA-LAA-left common carotid artery: 74.1% vs. 68.9%, p = .38). Although one-staged hybrid procedure has fewer complications in high-risk patients with lesions involving the distal aortic arch, the long-term survival rate is not optimistic.

Analysis of surgical strategies for children with epileptic spasms.

To investigate surgical prognostic factors in order to establish a surgical plan for children with drug-resistant epileptic spasms. We retrospectively analysed 64 children with drug-resistant spasms who were operated on in Beijing; the electroclinical features, surgical procedures, and surgical outcomes of these children were discussed in detail. We divided the seizure-free patients into several groups according to imaging, aetiology, and application of stereo-electroencephalography in order to investigate the extent of the various influencing factors. Fifty-three (82.8%) patients had favourable outcome, and 11 (17.2%) had unfavourable outcome. Based on the univariate analysis, the factors associated with favourable seizure outcome were interictal high γ frequency (χ 2 = 4.161; p = 0.041), concordance between MRI and interictal epileptic discharges (IEDs) (χ 2 = 6.148; p =0.013), and concordance between PET and IEDs (χ 2 = 4.281; p = 0.039). Concordance between MRI and IEDs (OR = 0.083, 95%CI = 0.014-0.483; p = 0.006) and continuous discharges on electrocorticography (OR = 0.109, 95%CI = 0.019-0.639; p = 0.014) were important factors associated with a favourable surgical outcome. Resective surgery is an effective treatment for drug-resistant ES in children. A deeper understanding of the predictors of seizure outcome is beneficial for establishing a standard, one-stage resection procedure for spasms in order to benefit more patients who have not previously considered surgery. We propose a workflow for presurgical evaluation in children with epileptic spasms.

Revision ACL Reconstruction: Principles and Practice.

The incidence of anterior cruciate ligament reconstruction (ACLR) surgeries is increasing and so is the number of revision surgeries for a failed ACLR. The spectrum of ACL failure includes symptoms of recurrent instability, pain, and/or stiffness. Factors contributing to ACL failure may be classified as patient-related, surgeon-related, and biological factors. Of these, tunnel malposition and recurrent trauma are the most common causes. Detailed patient assessment, imaging, and studying details of the index surgery are critical prior to planning revision surgery. Infection has to be ruled out prior to planning any reconstructive surgical procedure. Osseous malalignment in the coronal or sagittal planes would also need correction along with or prior to revision ACL surgery. Revision ACL reconstruction maybe performed as a one-stage or two-stage procedure. Severe tunnel dilatation, infection, or arthrofibrosis necessitates a two-stage approach. Autografts are preferred for revision ACL due their lesser re-tear rates and better outcomes. Associated meniscus tears and cartilage injuries are more common in revision than in primary surgery and need to be managed appropriately. Extra-articular reconstruction for controlling anterolateral instability is frequently required as well. Revision ACL reconstruction is a complex undertaking due to limited graft options, compromised anatomy and high frequency of associated injuries. Patient expectations must be tempered because functional outcomes and return to pre-injury sports are inferior to a primary surgery.