bluuebunny/crossref_metadata_2025 huggingface dataset:
Coronary vasospasm-induced syncope with dynamic changes of regional wall motion abnormalities confirmed real-time: a case report
Authors: Lee Hak Seung , Yang Han-Mo , Koo Bon-Kwon , Kim Hyo-Soo
Published: November 2020

Background

Coronary vasospasm is primarily characterized by transient and reversible vasoconstriction causing myocardial ischaemia and can manifest with various clinical features, including syncope.

Case summary

A 50-year-old man presented with recurrent episodes of syncope for 3 days. The last syncope history occurred during an early morning walk, accompanied by dizziness and loss of consciousness. There was no clear history of chest pain at the time. He smoked one pack of cigarettes daily and frequently consume alcohol. Approximately 3 h after admission, echocardiography initially revealed normal systolic function; however, during the examination, the patient suddenly complained of dizziness and regional wall motion abnormalities (RWMA) of the left anterior descending artery (LAD) territory were observed. Both RWMA and dizziness spontaneously improved within a few minutes. Emergency coronary angiography (CAG) was performed to confirm vasospasm. Coronary angiography revealed mild atherosclerosis of proximal LAD. After 3 min, he complained of dizziness and vague chest discomfort, and electrocardiogram revealed ST-segment elevation. We immediately performed angiography of the left coronary artery, and CAG revealed total occlusion of the proximal LAD without any provocation. After administration of intracoronary nitroglycerine, coronary flow was restored completely and ST-segment deviation normalized along with relief in chest discomfort. The patient’s symptoms have not recurred for 3 months while being on calcium channel blocker and long-acting nitrates.

Discussion

Coronary vasospasm can present as transient and dynamic myocardial ischaemia along with angina. Coronary vasospasm should always be considered in the differential diagnosis for syncope.
Case report: Metastatic cardiac calcifications in a patient with a history of rickets
Authors: Lopez Avecilla Matias , Corneli Mariana , Killinger Gisela , Rodriguez Correa Carlos
Published: November 2020

Background

Metastatic cardiac calcifications are often seen in patients with renal failure and dialysis associated with vascular calcification and calcifications in other organs. There is little to no evidence of metastatic cardiac calcification in patients with a history of rickets.

Case summary

A 40-year-old patient with a history of rickets treated in infancy and no personal history of cardiovascular or renal disease came for a periodical examination. Transthoracic echocardiogram showed an important calcification in the mitral annulus and the mitro-aortic junction. Computed tomography (CT) showed marked calcification affecting the heart fibrous skeleton. Coronary arteries were not affected.

Discussion

Distribution of heart calcification seen both with echocardiography and CT is important to report so they can be identified as dystrophic or metastatic. These two have different aetiologies so the description may help identify the possible cause.
Compromised chitin synthesis in lager yeast affects its Congo red resistance and release of mannoproteins from the cells
Authors: Omura Fumihiko , Takagi Motoshige , Kodama Yukiko
Published: November 2020

A mutant lager strain resistant to the cell wall-perturbing agent Congo red (CR) was isolated and the genetic alterations underlying CR resistance were investigated by whole genome sequencing. The parental lager strain was found to contain three distinct Saccharomyces cerevisiae (Sc)-type CHS6 (CHitin Synthase-related 6) alleles, two of which have one or two nonsense mutations in the open reading frame, leaving only one functional allele, whereas the functional allele was missing in the isolated CR-resistant strain. On the other hand, the Saccharomyces eubayanus-type CHS6 alleles shared by both the parental and mutant strains appeared to contribute poorly to chitin synthase-activating function. Therefore, the CR resistance of the mutant strain was attributable to the overall compromised activity of CHS6 gene products. The CR-resistant mutant cells exhibited less chitin production on the cell surface and smaller amounts of mannoprotein release into the medium. All these traits, in addition to the CR resistance, were complemented by the functional ScCHS6 gene. It is of great interest whether the frequent nonsense mutations found in ScCHS6 open reading frame in lager yeast strains are a consequence of the domestication process of lager yeast.
An efficient approximate method for solving two-dimensional fractional optimal control problems using generalized fractional order of Bernstein functions
Authors: Ketabdari Ali , Farahi Mohammad Hadi , Effati Sohrab
Published: November 2020

We define a new operational matrix of fractional derivative in the Caputo type and apply a spectral method to solve a two-dimensional fractional optimal control problem (2D-FOCP). To acquire this aim, first we expand the state and control variables based on the fractional order of Bernstein functions. Then we reduce the constraints of 2D-FOCP to a system of algebraic equations through the operational matrix. Now, one can solve straightforward the problem and drive the approximate solution of state and control variables. The convergence of the method in approximating the 2D-FOCP is proved. We demonstrate the efficiency and superiority of the method by comparing the results obtained by the presented method with the results of previous methods in some examples.
Genetically related micafungin-resistant Candida parapsilosis blood isolates harbouring novel mutation R658G in hotspot 1 of Fks1p: a new challenge?
Authors: Arastehfar Amir , Daneshnia Farnaz , Hilmioglu-Polat Süleyha , Ilkit Macit , Yasar Melike , Polat Furkan , Metin Dilek Yeşim , Dokumcu Ülküm Zafer , Pan Weihua , Hagen Ferry , Boekhout Teun , Perlin David S , Lass-Flörl Cornelia
Published: November 2020

Background

Echinocandin resistance rarely occurs in clinical Candida parapsilosis isolates and the underlying mechanism is unknown.

Objectives

To determine the prevalence of echinocandin resistance and the underlying mechanism for a large collection of C. parapsilosis blood isolates and to determine whether the echinocandin-resistant isolates were clonally related.

Methods

C. parapsilosis blood isolates (n = 213) were subjected to antifungal susceptibility testing (CLSI M27), for micafungin, anidulafungin, amphotericin B and, if appropriate, caspofungin. Hotspot (HS) 1 and HS2 of FKS1 were sequenced for all isolates (n = 213) and microsatellite typing was performed for echinocandin-resistant isolates.

Results

All isolates were susceptible to amphotericin B and two isolates were intermediate to anidulafungin (MIC = 4 mg/L), while micafungin resistance was noted in four isolates (MIC >8 mg/L); three of which were also fluconazole resistant and therefore were MDR. Interestingly, micafungin-resistant isolates, but not those intermediate to anidulafungin, carried novel mutation R658G in HS1 of Fks1p; three of which also harboured Y132F+K143R in Erg11. The first isolate (MICR1) was recovered in November 2017 from a patient admitted to paediatric gastroenterology who showed therapeutic failure under caspofungin treatment. MICR2–MICR4 were collected during 2018–19 and were recovered from three echinocandin-naive paediatric-surgery patients; the isolates shared the same genotype.

Conclusions

Herein, for the first time (to the best of our knowledge), we identified micafungin-resistant C. parapsilosis blood isolates harbouring a novel mutation in HS1 of FKS1, which was likely attributable to in vitro micafungin resistance and in vivo caspofungin therapeutic failure. The acquisition of micafungin-resistant C. parapsilosis isolates in echinocandin-naive patients likely implicates clonal expansion, as supported by the close genetic relatedness of MICR2–MICR4.
A case report of an incidental finding of congenital oesophageal diverticulum in a patient presenting with stridor
Authors: Limbu Raju , Brar Sabrina , Modayil Prince
Published: November 2020

Congenital oesophageal diverticulum is incredibly rare and has not commonly been published in the literature. Oesophageal diverticulum can be asymptomatic; however, symptoms such as dysphagia, regurgitation and chest discomfort may be present. We describe the case of a paediatric patient presenting with biphasic stridor, respiratory distress and cyanosis at birth, who was found to have a supraglottic cyst and later the presence of an oesophageal diverticulum shown on ultrasound imaging. There has been one other case reported in the literature of an oesophageal diverticulum presenting with stridor, and we therefore believe this is one of only two cases to illustrate this atypical presentation of congenital oesophageal diverticulum. It highlights the importance of a meticulous multidisciplinary team approach to patient care, as well as conducting appropriate investigations to aid early diagnosis to improve patient outcomes.
Systematic velocity drifts of methanol masers associated with G9.62+0.20E
Authors: MacLeod G C , Chibueze J O , Sanna A , Paulsen J D , Houde M , van den Heever S P , Goedhart S
Published: November 2020

The source G9.62+0.20E surprises again! Several of the associated 6.7- and 12.2-GHz methanol masers are experiencing contemporaneous and systematic velocity drifts. Both 6.7- and 12.2-GHz methanol features blueward of v = +1.2 km s−1 are blue shifting while those redward are red shifting. A best-fitting rotating Keplerian disc with a central mass of ∼12 M⊙, radii Rinner = 5 au and Router = 5000 au, and at an inclination angle of 22○ either precessing and/or experiencing infall explains these systematic velocity drifts. Also three more distinct 6.7-GHz methanol maser features are found to vary periodically; two very weak and one obviously periodic only after 2003. Evidence of periodicity is seen as early as 1992. Time lags are confirmed but the cause is unclear. It is possible this source will surprise again.
How to Make a Rodent Giant: Genomic Basis and Tradeoffs of Gigantism in the Capybara, the World’s Largest Rodent
Authors: Herrera-Álvarez Santiago , Karlsson Elinor , Ryder Oliver A , Lindblad-Toh Kerstin , Crawford Andrew J
Published: November 2020

Gigantism results when one lineage within a clade evolves extremely large body size relative to its small-bodied ancestors, a common phenomenon in animals. Theory predicts that the evolution of giants should be constrained by two tradeoffs. First, because body size is negatively correlated with population size, purifying selection is expected to be less efficient in species of large body size, leading to increased mutational load. Second, gigantism is achieved through generating a higher number of cells along with higher rates of cell proliferation, thus increasing the likelihood of cancer. To explore the genetic basis of gigantism in rodents and uncover genomic signatures of gigantism-related tradeoffs, we assembled a draft genome of the capybara (Hydrochoerus hydrochaeris), the world’s largest living rodent. We found that the genome-wide ratio of nonsynonymous to synonymous mutations (ω) is elevated in the capybara relative to other rodents, likely caused by a generation-time effect and consistent with a nearly neutral model of molecular evolution. A genome-wide scan for adaptive protein evolution in the capybara highlighted several genes controlling postnatal bone growth regulation and musculoskeletal development, which are relevant to anatomical and developmental modifications for an increase in overall body size. Capybara-specific gene-family expansions included a putative novel anticancer adaptation that involves T-cell-mediated tumor suppression, offering a potential resolution to the increased cancer risk in this lineage. Our comparative genomic results uncovered the signature of an intragenomic conflict where the evolution of gigantism in the capybara involved selection on genes and pathways that are directly linked to cancer.
HK022 bacteriophage Integrase mediated RMCE as a potential tool for human gene therapy
Authors: Elias Amer , Kassis Hala , Elkader Suha Abd , Gritsenko Natasha , Nahmad Alessio , Shir Hodaya , Younis Liana , Shannan Atheer , Aihara Hideki , Prag Gali , Yagil Ezra , Kolot Mikhail
Published: November 2020

HK022 coliphage site-specific recombinase Integrase (Int) can catalyze integrative site-specific recombination and recombinase-mediated cassette exchange (RMCE) reactions in mammalian cell cultures. Owing to the promiscuity of the 7 bp overlap sequence in its att sites, active ‘attB’ sites flanking human deleterious mutations were previously identified that may serve as substrates for RMCE reactions for future potential gene therapy. However, the wild type Int proved inefficient in catalyzing such RMCE reactions. To address this low efficiency, variants of Int were constructed and examined by integrative site-specific recombination and RMCE assays in human cells using native ‘attB’ sites. As a proof of concept, various Int derivatives have demonstrated successful RMCE reactions using a pair of native ‘attB’ sites that were inserted as a substrate into the human genome. Moreover, successful RMCE reactions were demonstrated in native locations of the human CTNS and DMD genes whose mutations are responsible for Cystinosis and Duchene Muscular Dystrophy diseases, respectively. This work provides a steppingstone for potential downstream therapeutic applications.
Brain network motif topography may predict emergence from disorders of consciousness: a case series
Authors: Nadin Danielle , Duclos Catherine , Mahdid Yacine , Rokos Alexander , Badawy Mohamed , Létourneau Justin , Arbour Caroline , Plourde Gilles , Blain-Moraes Stefanie
Published: November 2020

Neuroimaging methods have improved the accuracy of diagnosis in patients with disorders of consciousness (DOC), but novel, clinically translatable methods for prognosticating this population are still needed. In this case series, we explored the association between topographic and global brain network properties and prognosis in patients with DOC. We recorded high-density electroencephalograms in three patients with acute or chronic DOC, two of whom also underwent an anesthetic protocol. In these two cases, we compared functional network motifs, network hubs and power topography (i.e. topographic network properties), as well as relative power and graph theoretical measures (i.e. global network properties), at baseline, during exposure to anesthesia and after recovery from anesthesia. We also compared these properties to a group of healthy, conscious controls. At baseline, the topographic distribution of nodes participating in alpha motifs resembled conscious controls in patients who later recovered consciousness and high relative power in the delta band was associated with a negative outcome. Strikingly, the reorganization of network motifs, network hubs and power topography under anesthesia followed by their return to a baseline patterns upon recovery from anesthesia, was associated with recovery of consciousness. Our findings suggest that topographic network properties measured at the single-electrode level might provide more prognostic information than global network properties that are averaged across the brain network. In addition, we propose that the brain network’s capacity to reorganize in response to a perturbation is a precursor to the recovery of consciousness in DOC patients.
T-Cell Immune Surveillance in Allogenic Stem Cell Transplant Recipients: Are Whole Blood–Based Assays Ready to Challenge ELISPOT?
Authors: Lauruschkat Chris D , Page Lukas , Etter Sonja , Weis Philipp , Gamon Florian , Kraus Sabrina , Einsele Hermann , Wurster Sebastian , Loeffler Juergen
Published: November 2020

We compared the feasibility of 4 cytomegalovirus (CMV)- and Aspergillus-reactive T-cell immunoassay protocols in allogenic stem cell transplant recipients. While enzyme-linked immunospot performed best overall, logistically advantageous whole blood–based assays performed comparably in patients with less severe lymphocytopenia. CMV-induced interferon-gamma responses correlated strongly across all protocols and showed high concordance with serology.
Structure- and sequence-based design of synthetic single-domain antibody libraries
Authors: Sevy Alexander M , Chen Ming-Tang , Castor Michelle , Sylvia Tyler , Krishnamurthy Harini , Ishchenko Andrii , Hsieh Chung-Ming
Published: November 2020

Single-domain antibody fragments known as VHH have emerged in the pharmaceutical industry as useful biotherapeutics. These molecules, which are naturally produced by camelids, share the characteristics of high affinity and specificity with traditional human immunoglobulins, while consisting of only a single heavy chain. Currently, the most common method for generating VHH is via animal immunization, which can be costly and time-consuming. Here we describe the development of a synthetic VHH library for in vitro selection of single domain binders. We combine structure-based design and next-generation sequencing analysis to build a library with characteristics that closely mimic the natural repertoire. To validate the performance of our synthetic library, we isolated VHH against three model antigens (soluble mouse PD-1 ectodomain, amyloid-β peptide, and MrgX1 GPCR) of different sizes and characteristics. We were able to isolate diverse binders targeting different epitopes with high affinity (as high as 5 nM) against all three targets. We then show that anti-mPD-1 binders have functional activity in a receptor blocking assay.
A meta-analysis of accelerometer sleep outcomes in healthy children based on the Sadeh algorithm: the influence of child and device characteristics
Authors: van Kooten Jojanneke A M C , Jacobse Sofie T W , Heymans Martijn W , de Vries Ralph , Kaspers Gertjan J L , van Litsenburg Raphaële R L
Published: November 2020

Study Objectives

Children often experience sleep problems, with a negative impact on mood, behavior, cognitive function, and other aspects of mental and physical health. Accelerometers are widely used to assess sleep, but general reference values for healthy children do not yet exist. The aim of this meta-analysis was to determine mean values for wake after sleep onset (WASO), sleep efficiency (SE), total sleep time (TST) and sleep onset latency (SOL), and to determine the effect of child and accelerometer-characteristics.

Methods

A search included studies with healthy children, 0–18 years, reporting WASO, SE, TST, and/or SOL, calculated with the Sadeh algorithm. Meta-analyses with random effects produced pooled estimate means per outcome. Meta-regression analyses determined the effect of age, sex, placement site and accelerometer type.

Results

Eighty-three studies (9,068 participants) were included. Pooled means were 63 min (95% CI 57 to 69) for WASO, 88% (95% CI 87 to 89) for SE, 477 min (95% CI 464 to 491) for TST and 19 min (95% CI 17 to 22) for SOL. Heterogeneity was high (95%–99%). TST decreased with age and there was an age-effect on SOL. SE differed between wrist and ankle (used in age 0–24 months) placement, and between piezoelectric and MEMS-type accelerometers. No differences were found between boys and girls, although this number of studies was small.

Conclusions

We found differences in almost all investigated outcomes and heterogeneity was high. Therefore, we advise to use a study-specific control sample until more robust reference values are available. Future research should narrow the methodological heterogeneity and produce larger datasets, needed to establish these reference values.
Effect of microbial feed additives on growth performance, microbial protein synthesis, and rumen microbial population in growing lambs
Authors: Direkvandi Ehsan , Mohammadabadi Tahereh , Salem Abdelfattah Z M
Published: November 2020

Arabi lambs (n =28; body weight = 24 ± 3.7 kg; average age = 120 ± 8 days) were used to investigate the effect of microbial additives on growth performance, microbial protein synthesis and rumen microbial population of fattening lamb based on completely randomized design. Four treatments were studied: (1) control (without additive; CON); (2) Lactobacillus fermentum and L. plantarum (FP); (3) Saccharomyces cerevisiae (SC) plus FP (SCFP); and (4) Megasphaera elsdenii plus SCFP (MSCFP). Lambs were inoculated before morning feeding (daily oral dosed) with a 50 mL microbial suspension as follows: FP, 50 mL bacterial suspension containing 4.5 × 108 colony-forming unit per day (cfu/d) of L. plantarum and L. fermentum (in ratio 50:50); SCFP, 50 mL microbial suspension containing 4.5 × 108 cfu/d FP and 1.4 × 1010 cfu/d SC; MSCFP, 50 mL microbial suspension containing 4.5 × 108 cfu/d Me, 4.5 × 108 cfu/d FP and 1.4 × 1010 cfu/d SC. Feed intake and body weight of lambs were not affected by microbial additives. Average daily gain and feed efficiency were increased on day 0 to 21. The highest concentration of uric acid, total excreted purine derivatives (PD), microbial N, microbial CP, and metabolizable protein were in MSCFP lambs. The ruminal population of Ruminococcus albus and Ruminococcus flavefaciens was higher in MSCFP and SCFP than CON and FP lambs. The highest and the lowest abundance of M. elsdenii and methanogen respectively was observed in lambs fed on microbial additives. The tendency to improve growth performance vs. CON may be due to improvements in microbial protein synthesis and microbial populations, especially fiber-degrading bacteria. The decrease in the population of methanogens as a result of the use of microbial additives is another positive result.
Management of primary vasculitides with biologic and novel small molecule medications
Authors: Serling-Boyd Naomi , Wallace Zachary S.
Published: November 2020

Purpose of review

Vasculitides can affect small, medium and/or large vessels, leading to end-organ damage, decreased quality of life and death. Glucocorticoids remain the backbone of treatment for systemic vasculitis but are associated with numerous toxicities. In recent years, the efficacy of glucocorticoid-sparing biologic and novel small molecule therapies has been demonstrated.

Recent findings

In giant cell arteritis, tocilizumab was superior to glucocorticoid monotherapy in maintenance remission and cumulative glucocorticoid exposure and is now approved for the treatment of giant cell arteritis. In addition to the previously demonstrated efficacy of rituximab for remission induction in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, recent trials have also demonstrated its superiority for remission maintenance compared to alternative approaches. Mepolizumab is superior to standard of care alone with regard to remission rates and glucocorticoid-sparing effect in refractory eosinophilic granulomatosis with polyangiitis. Avacopan has shown significant promise in ANCA-associated vasculitis as part of a glucocorticoid-free induction regimen in a recently completed phase 3 trial. Use of biologics in rarer vasculitides remains guided by reports from small case series.

Biologics and other novel therapies have an increasingly important role in the management of systemic vasculitis. Additional studies are needed to define their optimal use and to guide their use in more rare forms of vasculitis.
Plate Versus Lag Screw Only Fixation of Unstable Ankle Fractures Involving the Fibula in Adolescent Patients
Authors: Paez Conner J. , Lurie Benjamin M. , Bomar James D. , Upasani Vidyadhar V. , Pennock Andrew T.
Published: November 2020

Background:

Plate fixation has been the traditional technique for fracture repair of unstable ankle injuries with an associated lateral malleolus fracture. Recently, biomechanical and clinical data have demonstrated lag screw only fixation to be an effective alternative to plate fixation in the adult population. This comparison has yet to be studied in the adolescent or pediatric population. The objective of this study was to compare lag screw only fixation with traditional plating for lateral malleolus fractures in adolescents.

Methods:

A retrospective review was conducted of 83 adolescents with unstable oblique lateral malleolus fractures treated at a single pediatric level-1 trauma center between 2011 and 2019 with a minimum clinical follow-up until fracture union. Patients were divided into 2 surgical groups: (1) plate fixation (n=51) or (2) lag screw fixation (n=32). Radiographic and clinical outcomes and complications were measured in both groups.

Results:

All patients in both groups achieved our primary outcome measure of fracture union without loss of reduction. The mean surgical time for subjects treated with a plate was 15 minutes longer (64 vs. 49 min) (P=0.001) and these patients were 3.8 times more likely to have symptomatic implants (P<0.044) than subjects treated with screws. Approximately 50% of the cohort was available by phone for patient-reported outcomes at a mean follow-up of 50 months. The mean Single Assessment Numerical Evaluation scores, Foot and Ankle Ability Measure Activities of Daily Living scores, Foot and Ankle Ability Measure sports scores, and return to sports rates were similar (92 vs. 93, 98.2 vs. 98.1, 93.2 vs. 94.0, 95% vs. 86%, respectively; P>0.05) between the 2 treatment methods.

Conclusions:

Lag screw only fixation is a safe and effective procedure for noncomminuted, oblique fibula fractures in the adolescent population as demonstrated by equivalent fracture healing rates without loss of reduction and similar outcome scores. Given these comparable results with the additional benefits of shorter surgical time and less symptomatic implants, lag screw only fixation should be considered as a viable treatment alternative to traditional lateral plating in the adolescent population.

Level of Evidence:

Level III.
Part-time Abduction Bracing in Infants With Residual Acetabular Dysplasia: Does Compliance Monitoring Support a Dose-dependent Relationship?
Authors: Swarup Ishaan , Talwar Divya , Sankar Wudbhav N.
Published: November 2020

Introduction:

Residual acetabular dysplasia is often seen after successful Pavlik treatment or during follow-up for infants with risk factors for developmental dysplasia of the hip. A previous study supported the effectiveness of part-time abduction bracing for treating this residual dysplasia. However, the relationship between time in the brace and acetabular improvement was not established given the lack of compliance data. The purpose of this prospective study was to validate the effect of part-time bracing on acetabular dysplasia and determine if a dose-dependent relationship exists.

Methods:

Eligibility criteria included infants ~6 months of age with an AP pelvic radiograph demonstrating acetabular dysplasia, defined as an acetabular index (AI) ≥30 degrees. After obtaining informed consent, a rigid abduction orthosis was prescribed with a thermal compliance sensor. Patients were instructed to wear the brace for nights/naps and follow-up at 1 year of age for repeat radiograph. AIs were measured by the senior author who was blinded to the compliance data. Hours of wear were compared with changes in AI over the study period using descriptive statistics and a generalized estimating equation model.

Results:

Our series consisted of 26 infants (36 hips) with a mean age at enrollment of 5.9 months (range, 4.9 to 7.9); 84.6% were female individuals. At a mean follow-up of 6 months (range, 5.1 to 8.2), average wear time/day was 11.5 hours (range, 1.3 to 21.7), and total time in brace averaged 1698 hours (range, 218 to 3244 hours). The mean improvement in AI over the study period was 4.8 degrees (95% confidence interval, 3.9-5.5 degrees). The authors found a significant correlation between average hours of brace wear per day and improvement in AI (r=0.36, P<0.05), a relationship that remained significant in our multivariate model after adjusting for confounders.

Conclusions:

Part-time abduction bracing is effective for treating residual dysplasia, with the degree of improvement in AI correlating with hours of brace wear per day. Given this dose-dependent relationship, the optimal hours of wear may depend on the severity of residual dysplasia and the tolerance of the child and family to bracing.
Quadriceps Strength Is Influenced by Skeletal Maturity in Adolescents Recovering From Anterior Cruciate Ligament Reconstruction
Authors: Casp Aaron J. , Bodkin Stephan G. , Kew Michelle E. , Noona Sean W. , Lesevic Milos , Hart Joseph M. , Diduch David
Published: November 2020

Background:

Anterior cruciate ligament injuries and anterior cruciate ligament reconstructions (ACLRs) are common, especially in adolescent patients. Recovery of strength, jumping performance, and perceived/subjective function are often used to make a return to sports decisions after injury. It is unknown how skeletal maturity may influence strength recovery after ACLR. The purpose of this study was to compare the strength and patient-reported outcomes in adolescent ACLR patients with and without open distal femur and proximal tibia physes.

Methods:

One hundred seventeen consecutive patients under the age of 18 were referred for routine strength and subjective outcomes evaluation following ACLR, 100 were included in the final analyses after excluding those with prior injuries, those tested outside for 4 to 12 month postoperative window, and those with incomplete clinical data. All study patients completed patient-reported outcomes, and underwent isometric and isokinetic testing of knee extensor and flexor strength to calculate normalized peak torque and limb symmetry. Statistical analyses were performed on all outcomes data using a 2×2 (physeal status: open, closed; and sex: male, female) with analysis of covariance where age and preoperative activity level were used as covariates.

Results:

A significant interaction between sex and physeal status for isokinetic knee extension peak torque and isometric knee extension peak torque, and limb symmetry index was found. This indicated that males with open physes were stronger and more symmetric than males with closed physes and females with open physes at ~6 months post-ACLR. There were no differences between sexes for patients with closed physes. No interactions were observed for flexion strength. Male patients and patients with open physes had higher perceived knee function compared with their corresponding counterparts.

Conclusions:

After ACLR, adolescent patients with open physes had higher quadriceps strength compared with patients with closed physes. Overall, those skeletally less mature patients actually fared better on the functional strength tests, suggesting that functional recovery is not hindered by the presence of an incompletely closed physis.

Level of Evidence:

Level III—retrospective comparative study.
What is the Optimal Surgical Method for Achieving Correction and Avoiding Neurological Complications in Pediatric High-grade Spondylolisthesis?
Authors: Rocos Brett , Strantzas Samuel , Zeller Reinhard , Lewis Stephen , Tan Tony , Lebel David
Published: November 2020

Background:

Controversy persists in the treatment of high-grade spondylolisthesis (HGS). Surgery is recommended in patients with intrusive symptoms and evidence debates the competing strategies. This study compares the radiologic outcomes and postoperative complications at a minimum of 2 years follow-up for patients with HGS treated with instrumented fusion with partial reduction (IFIS) with those treated with reduction, decompression, and instrumented fusion (RIF). We hypothesize that IFIS leads to a lower rate of complication and revision surgery than RIF.

Methods:

A retrospective comparative methodology was used to analyze consecutive HGS treated surgically between 2006 and 2017. Patients diagnosed with ≥grade 3 spondylolisthesis treated with arthrodesis before the age of 18 years with a minimum of 2 years follow-up were included. Patients were excluded if surgery did not aim to achieve arthrodesis or was a revision procedure. Cases were identified through departmental and neurophysiological records.

Results:

Thirty patients met the inclusion criteria. Mean follow-up was 4 years. Ten patients underwent IFIS and the remaining 20 underwent RIF. The 2 groups showed no difference in demographics, grade of slip, deformity or presenting symptoms. Of 10 treated with IFIS, the SA reduced by a mean of 10 degrees and C7 sagittal vertical line changed by 31 mm. In the RIF cohort, SA reduced by 16 degrees and C7 sagittal vertical line reduced by 26 mm. PT was unchanged in both groups. In IFIS cohort, 2 patients showed postoperative weakness, resolved by 2 years. None required revision surgery. In the RIF group, 4 sustained dural tears and 1 a laminar fracture, 7 showed postoperative weakness or dysaesthesia, 3 of which had not resolved by 2 years. Eight patients underwent unplanned further surgery, 3 for pseudarthrosis.

Conclusions:

RIF and IFIS show similar radiologic outcomes. RIF shows a higher rate of unplanned return to surgery, pseudarthrosis and persisting neurological changes.

Level of Evidence

Level III—retrospective comparative study.
Can Chiari Osteotomy Favorably Influence Long-term Hip Degradation in Multiple Epiphyseal Dysplasia and Pseudoachondroplasia?
Authors: Andrzejewski Aurélie , Péjin Zagorka , Finidori Georges , Badina Alina , Glorion Christophe , Wicart Philippe
Published: November 2020

Background:

Multiple epiphyseal dysplasia (MED) and pseudoachondroplasia (PSACH) are congenital skeletal disorders characterized by irregular epiphyses, mild or severe short stature and early-onset osteoarthritis which frequently affect the hips. The current study evaluates the long-term results of the Chiari osteotomy in MED and PSACH patients.

Methods:

Twenty patients (14 MED and 6 PSACH) were retrospectively included. Clinical assessment used the Postel Merle d’Aubigné (PMA) score and the Hip disability and Osteoarthritis Outcome Score (HOOS). Risser index, Sharp angle, acetabular depth index, center-edge angle, Tönnis angle, and femoral head coverage were measured on the preoperative radiographs and at last follow-up. The Treble index, which identifies the hip at risk in MED patients, was also determined. Stulberg classification (grades I to V) was used to evaluate the risk of osteoarthritis in the mature hips.

Statistical analyses determined differences between preoperative and postoperative data. The Kaplan Meier method was used to calculate the survival rate of the operated hips using total hip arthroplasty as the endpoint.

Results:

Thirty-three hips which underwent a Chiari osteotomy were reviewed. The average follow-up was 20.1 years. The PMA scores were significantly better at last follow-up than preoperatively. All radiographic parameters significantly improved. Moreover, the Sharp angle, center-edge angle, and femoral head coverage improved to a normal value at hip maturity. All of the operated hips had a Treble index of type I. At hip maturity, a majority of hip were aspherical congruent (Stulberg grades of III and IV). The survival rate of the operated hips was 80.7% at 24 years postoperative.

Conclusions:

The Chiari osteotomy is a satisfying solution for severe symptomatic hip lesions in MED and PSACH patients. At long-term follow-up, this procedure lessens pain and improves hip function, which delays total hip arthroplasty indication.

Level of Evidence:

Level IV.
Anatomic Relationship of the Femoral Neurovascular Bundle in Patients With Congenital Femoral Deficiency
Authors: Huser Aaron J. , Kwak Yoon Hae , Rand Troy J. , Paley Dror , Feldman David S.
Published: November 2020

Background:

Congenital femoral deficiency (CFD) is a rare condition that affects the morphology of the hip and surrounding soft tissues. Bony deformity and distorted muscular anatomy are well known, but no studies have described the relationship of the femoral neurovascular (NV) bundle to surgically relevant anatomic landmarks. The authors compared the location of the femoral NV bundle on the affected side in patients with CFD with the unaffected side. The authors hypothesized that the bundle on the pathologic side would be in an abnormal position relative to the unaffected side.

Methods:

Thirty-three patients diagnosed with unilateral CFD who had undergone preoperative magnetic resonance imaging of the pelvis were included in our study. The authors identified the femoral NV bundle on the axial cuts and measured its distance from the anterior superior iliac spine (ASIS), anterior inferior iliac spine (AIIS), and lesser trochanter (LT). Anatomic percent change and absolute measurements were then compared and correlated with associated boney deformities and the Paley classification.

Results:

The distance from the femoral NV bundle to the ASIS, AIIS, and LT was significantly different compared with the unaffected side. The AIIS absolute distance and AIIS percent change significantly correlated with the neck-shaft angle of the proximal femur.

Conclusions:

In patients with CFD, the femoral NV bundle seems to be further from the LT and closer to the AIIS on the affected side when compared with the unaffected side. magnetic resonance imaging may be helpful to understand the course of the femoral NV bundle before reconstruction in patients with CFD; however, the authors recommend identification of the femoral NV bundle before transection of the proximal rectus femoris tendon to provide safe surgical care.

Level of Evidence:

Level IV—case-control study of diagnostic studies.
Hand Bone Age Radiography: Comparison Between Slot-scanning and Conventional Techniques
Authors: Nguyen Jie C. , Guariento Andressa , Nicholson Anthony , Nguyen Michael K. , Gendler Liya , Ho-Fung Victor , Zhu Xiaowei , Talwar Divya , Darge Kassa , Flynn John M. , Cahill Patrick J.
Published: November 2020

Background:

Determination and longitudinal monitoring of progressive skeletal maturity are essential in the management of children with scoliosis. Although different methods for determining skeletal maturity exists, the most widely practiced method relies on the ossification pattern of the bones of the hand and wrist, which is traditionally acquired using conventional techniques and after the acquisition of the spine using the low-dose slot-scanning technique. Whereas the existing published literature has published promising results on the use of the slot-scanning technique to acquire these hand and wrist radiographs, image quality and radiation dose have not been systematically compared between these techniques. Thus, the objective of our study is to compare image quality, interpretation reliability, and radiation dose of hand bone age radiographs between slot-scanning and conventional techniques using age- and sex-matched children.

Methods:

This retrospective study included children who underwent hand radiographs using slot-scanning between October 1, 2019 and December 31, 2019; and matched children who underwent conventional radiography. Blinded to technique, 5 readers reviewed all radiographs after randomization to rate image quality and to determine bone age using the Greulich and Pyle classification. Dose area product was recorded. Mann-Whitney and t tests were used to compare variables between techniques and intraclass correlation (ICC) to determine observer agreement.

Results:

Our study cohort of 194 children (128 girls, 66 boys; mean age: 13.7±2.3 y) included 97 slot-scanning and 97 conventional radiographs. One (1%) slot-scanning and no conventional radiograph was rated poor in image quality. There was almost perfect interpretation reliability with slot-scanning with high interobserver (ICC=0.948) and intraobserver (ICC=0.996) agreements, comparable with conventional radiographs (ICCs=0.919 and 0.996, respectively). Dose area product (n=158) was lower (P<0.002) with slot-scanning than with conventional techniques.

Conclusion:

Almost perfect interobserver reliability and intraobserver reproducibility with slot-scanning radiographs (performed using significantly lower radiation doses) suggest that this technique for hand bone age determination can be a reliable adjunct to scoliosis monitoring.

Level of Evidence:

Level III.
Three-dimensional Analysis of Acetabular Morphology and Orientation in Patients With Slipped Capital Femoral Epiphysis
Authors: Paez Conner J. , Bomar James D. , Farnsworth Christine L. , Bandaralage Harsha , Upasani Vidyadhar V.
Published: November 2020

Background:

Previous studies analyzing the acetabuli in patients with slipped capital femoral epiphysis (SCFE) have not definitively addressed the relationship between SCFE and acetabular shape. Femoral head overcoverage and acetabular version are thought to contribute to SCFE. The purpose of this study was to determine the acetabular morphology and orientation in hips with SCFE and compare them with normally developing children.

Methods:

Pelvic computed tomography (CT) images of patients with SCFE were compared with pelvic CTs of patients without orthopedic abnormalities (normal controls). Three-dimensional (3-D) reconstructions were created from each CT examination. Custom software uniformly aligned the pelvis then determined acetabular measures from the reconstructions including acetabular version, acetabular tilt, articular surface area, and acetabular coverage angle measured in a radial manner dividing the acetabulum into octants.

Results:

Two-hundred forty-four hips were included (53 SCFE, 31 unaffected contralateral hips in patients with SCFE, and 160 controls). The acetabular version was similar among SCFE hips, unaffected contralateral hips, and normal controls (P=0.48). Control hips had higher acetabular tilt than SCFE-affected hips (P=0.01) and unaffected contralateral hips (P=0.04). The acetabular surface area was higher in SCFE-affected hips compared with controls (P<0.05). SCFE-affected hips and the unaffected contralateral hips in patients with SCFE had increased acetabular coverage compared with controls in all 5 acetabular octants.

Conclusions:

Contrary to some previous studies, the authors did not find the acetabulum to be retroverted in patients with SCFE compared with controls. Both affected and unaffected hips of patients with SCFE have decreased acetabular tilt. Acetabular surface area is higher in hips with SCFE compared with normal controls, and both the SCFE-affected hips and unaffected hips had increased acetabular coverage compared with controls in all 5 octants of the acetabulum. The shared morphology of affected and unaffected hips in patients with SCFE suggests that their acetabular anatomy may predispose them to slip.

Level of Evidence:

Level III.
Pollicization of the Index Finger in the Treatment of Thumb Hypoplasia
Authors: Mendez Manuel , Parot Catalina , Pino Paula , Concha Elias , Carrasco Marcia , Mendez Magdalena
Published: November 2020

Pollicization of the index finger allows to reconstruct the hand’s ability to pinch and grasp. It has been broadly used to address traumatic loss of the thumb. Today it is the procedure of choice for severe congenital thumb hypoplasia. It allows children prehension of small and large objects and gives the hand a more normal appearance. This is a demanding technique with well-defined and perfected steps that, if carefully performed, can minimize complications.
Using Extensor Retinaculum to Reconstruct the Thumb Metacarpophalangeal Joint Ulnar Collateral Ligament
Authors: Mastella Daniel , Gorski John , Ashmead Duffield , Wollstein Ronit
Published: November 2020

Chronic complete tears of the ulnar collateral ligament of the thumb metacarpophalangeal joint often require surgical reconstruction. The indications, materials used, and the methods for reconstruction remain controversial. We describe a technique for reconstruction that utilizes a slip of the extensor retinaculum for reconstruction. The advantages of extensor retinaculum as a graft choice are that it matches the native ligament with a synovial and nonsynovial surface, has elasticity similar to the ligament and minimal donor site morbidity. Reconstruction of the ulnar collateral ligament with this graft successfully restores pinch.
Effects of 5% Albumin Plus Saline Versus Saline Alone on Outcomes From Large-Volume Resuscitation in Critically Ill Patients
Authors: Gomez Hernando , Priyanka Priyanka , Bataineh Ayham , Keener Christopher M. , Clermont Gilles , Kellum John A.
Published: November 2020

OBJECTIVES:

To compare 5% albumin with 0.9% saline for large-volume resuscitation (> 60 mL/Kg within 24 hr), on mortality and development of acute kidney injury.

DESIGN:

Retrospective cohort study.

SETTING:

Patients admitted to ICUs in 13 hospitals across Western Pennsylvania. We analyzed two independent cohorts, the High-Density Intensive Care databases: High-Density Intensive Care-08 (July 2000 to October 2008, H08) and High-Density Intensive Care-15 (October 2008 to December 2014, H15).

PATIENTS:

Total of 18,629 critically ill patients requiring large-volume resuscitation.

INTERVENTIONS:

Five percent of albumin in addition to saline versus 0.9% saline.

MEASUREMENTS AND MAIN RESULTS:

After excluding patients with acute kidney injury prior to large-volume resuscitation, 673 of 2,428 patients (27.7%) and 1,814 of 16,201 patients (11.2%) received 5% albumin in H08 and H15, respectively. Use of 5% albumin was associated with decreased 30-day mortality by multivariate regression in H08 (odds ratio 0.65; 95% CI 0.49–0.85; p = 0.002) and in H15 (0.52; 95% CI 0.44–0.62; p < 0.0001) but was associated with increased acute kidney injury in H08 (odds ratio 1.98; 95% CI 1.56–2.51; p < 0.001) and in H15 (odds ratio 1.75; 95% CI 1.58–1.95; p < 0.001). However, 5% albumin was not associated with persistent acute kidney injury and resulted in decreased major adverse kidney event at 30, 90, and 365 days. Propensity matched analysis confirmed similar associations with mortality and acute kidney injury.

CONCLUSIONS:

During large-volume resuscitation, 5% albumin was associated with reduced mortality and major adverse kidney event at 30, 90, and 365 days. However, a higher rate of acute kidney injury of any stage was observed that did not translate into persistent renal dysfunction.
Practitioner’s Guide to Latent Class Analysis: Methodological Considerations and Common Pitfalls
Authors: Sinha Pratik , Calfee Carolyn S. , Delucchi Kevin L.
Published: November 2020

Latent class analysis is a probabilistic modeling algorithm that allows clustering of data and statistical inference. There has been a recent upsurge in the application of latent class analysis in the fields of critical care, respiratory medicine, and beyond. In this review, we present a brief overview of the principles behind latent class analysis. Furthermore, in a stepwise manner, we outline the key processes necessary to perform latent class analysis including some of the challenges and pitfalls faced at each of these steps. The review provides a one-stop shop for investigators seeking to apply latent class analysis to their data.