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1.
Curr Genomics ; 21(7): 504-511, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33214766

RESUMO

BACKGROUND: In this study, whole genome re-sequencing of rust resistant soybean genotype EC241780 was performed to understand the genomic landscape involved in the resistance mechanism. METHODS: A total of 374 million raw reads were obtained with paired-end sequencing performed with Illumina HiSeq 2500 instrument, out of which 287.3 million high quality reads were mapped to Williams 82 reference genome. Comparative sequence analysis of EC241780 with rust susceptible cultivars Williams 82 and JS 335 was performed to identify sequence variation and to prioritise the candidate genes. RESULTS: Comparative analysis indicates that genotype EC241780 has high sequence similarity with rust resistant genotype PI 200492 and the resistance in EC241780 is conferred by the Rpp1 locus. Based on the sequence variations and functional annotations, three genes Glyma18G51715, Glyma18G51741 and Glyma18G51765 encoding for NBS-LRR family protein were identified as the most prominent candidate for Rpp1 locus. CONCLUSION: The study provides insights of genome-wide sequence variation more particularly at Rpp1 loci which will help to develop rust resistant soybean cultivars through efficient exploration of the genomic resource.

2.
Phys Chem Chem Phys ; 21(5): 2771-2782, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30667010

RESUMO

In organic semiconductors, optical absorption is pivotal for the performance of optoelectronic devices. The absorption by the semiconductors generates excitons which dissociate into free charge carriers, resulting in energy conversion. Although high performance has been achieved in non-fullerene organic solar cells, their charge generation behavior is far from being well understood. Keeping this in view, we have employed optical spectroscopic tools to study the charge generation mechanism in FLR (1,6,7,10-tetramethylfluoranthene) as a non-fullerene electron acceptor blended with P3HT (poly(3-hexylthiophene)) as an electron donor in five different solvents. Through steady state UV-visible and photoluminescence spectroscopy, we provide a basic understanding of charge transport by enlightening the influence of solvents on the aggregation behavior and exciton bandwidth. Furthermore, for the first time, by employing ultrafast vis-NIR transient absorption spectroscopy, we address the ultrafast charge generation and charge separation mechanism with systematic variation in solvent polarity by incorporating the time evolution of the transient species under various pump-probe wavelengths in the range of 450 nm to 1600 nm. For the different excitation wavelengths, the lifetime kinetics have been depicted by their multiexponential fits. The results show a fast decay term at a lifetime of a few picoseconds (ps) (∼1 to 5 ps) and a slow decay term at a lifetime of ∼500 ps. The charge generation in the P3HT:FLR blend proceeds on a ps time scale, which implies good intermixing of the components. It is clearly established that the non-halogenated solvents influence this aggregation behavior and higher conjugation lengths with higher photoluminescence quenching contribute to the higher charge generation. The enhanced polaron population in P3HT with the addition of FLR illustrates the importance of this acceptor material in the blend because a good solvent-material combination is essential to enhance the charge generation. As such, this comprehensive study explicitly shows the role of FLR as an emerging efficient non-fullerene acceptor for further improving the performance of devices.

3.
Physiol Mol Biol Plants ; 25(2): 387-398, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30956422

RESUMO

A set of 90 Indian soybean landraces were analysed for polymorphism at 43 SSRs and five allele specific markers of four major genes involved in regulating flowering and photoperiod response. A total of 42 polymorphic SSRs had amplified 126 alleles which served as raw data for estimation of genetic relationship and population structure among 90 accessions. Rare alleles of four and three SSRs were detected in accessions IC18768 and IC15089, respectively. Gene diversity in the population ranges from 0.065 to 0.717 with a mean value of 0.411. The polymorphism information content of 42 SSRs varied from 0.063 to 0.668. Hierarchical clustering based on neighbour-joining method identified three major clusters among 90 soybean accessions. Model based population structure analysis divided the 90 soybean accessions into four populations (K = 4). Mean value of Fst for different populations ranged between 0.4143 and 0.7239. Genotyping of 90 accessions with allele specific markers had identified accession IC15089 as triple recessive mutant of flowering genes E1, E2 and photoperiod sensitivity gene E3. The triple mutant IC15089 (e1, e3, e3) had been characterized phenotypically and identified as early maturing (88 days) and photoperiod insensitive genotype under extended photoperiod. The present study characterized genetic relationship among 90 Indian soybean landraces and had identified a few diverse and unique genotypes for utilization in soybean breeding programmes targeting development of short duration and photoperiod insensitive varieties through marker assisted selection.

4.
Phys Chem Chem Phys ; 20(25): 17304-17312, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29901685

RESUMO

A key challenge for researchers in the field of organic solar cells (OSCs) is to develop a physical model for a device that correctly describes the charge carrier transport phenomenon. In this article, an analytical study on the charge carrier transport phenomenon in an OSC is reported, which expresses a balance between free charge carrier generation and recombination in low mobility PTB7:PC71BM blend layers. First, the current density-voltage (J-V) data for the fabricated OSC were extracted from experiments by varying the incident power light intensity (IPL) and then analysis through theoretical simulation was used to quantify the dominant interface recombination parameters limiting the device's performance. It was found that although the generation of free charge carriers increased at higher IPL values, the performance of the device remained low due to poor electrical transport properties which resulted in a considerable accumulation of generated charge carriers in the active layer. Therefore, it has become important to work out the complex relation between charge carrier mobility, exciton-recombination dynamics and the overall electrical performance parameters in a single framework. This article explains the influence of incident power light intensity and charge carrier mobility on performance parameters, which limits the power conversion efficiency (PCE) of the OSC. The presented analysis could be helpful in optimizing the architecture of future devices to increase the PCE of OSCs.

5.
Phys Chem Chem Phys ; 19(38): 26169-26178, 2017 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-28930319

RESUMO

The design and fabrication of better excitonic solar cells are the need of the hour for futuristic energy solutions. This designing needs a better understanding of the charge transport properties of excitonic solar cells. One of the popular methods of understanding the charge transport properties is the analysis of the J-V characteristics of a device through theoretical simulation at varied illumination intensity. Herein, a J-V characteristic of a polymer:fullerene based bulk heterojunction (BHJ) organic solar cells (OSCs) of structure ITO/PEDOT:PSS (∼40 nm)/PTB7:PC71BM (∼100 nm)/Al (∼120 nm) is analyzed using one- and two-diode models at varied illumination intensity in the range of 0.1-2.33 Sun. It was found that the double diode model is better with respect to the single diode model and can explain the J-V characteristics of the OSCs correctly. Further, the recombination mechanism is investigated thoroughly and it was observed that fill factor (FF) is in the range of 62.5%-41.4% for the corresponding values of the recombination-to-extraction ratio (θ) varying from 0.001 to 0.023. These findings are attributed to the change in charge transport mechanism from trap-assisted to bimolecular recombination with the variation of illumination intensity.

6.
Langmuir ; 32(17): 4346-51, 2016 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-27079750

RESUMO

A new thermoreversible organogel based on diketopyrrolopyrrole dye (DPP-NCO) is reported for the first time and evolved as a new building block for the fabrication of 1D supramolecular assembly. AFM analysis illustrated that its gel state is composed of different sized 1D rods. DPP-NCO gel used as an additive in organic solar cells yields high efficiency of 7.9% owing to better nanophase separation of its active layer.

7.
Angew Chem Int Ed Engl ; 55(40): 12334-7, 2016 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-27573022

RESUMO

A new low-band gap dyad DPP-Ful, which consists of covalently linked dithiafulvalene-functionalized diketopyrrolopyrrole as donor and fullerene (C60 ) as the acceptor, has been designed and synthesized. Organic solar cells were successfully constructed using the DPP-Ful dyad as an active layer. This system has a record power-conversion efficiency (PCE) of 2.2 %, which is the highest value when compared to reported single-component organic solar cells.

8.
Acc Chem Res ; 47(5): 1465-74, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24785408

RESUMO

Since the discovery of high conductivity in iodine-doped polyacetylene, many interesting conducting polymers have been developed. Of these, polythiophenes have been most studied as electronic materials, with poly(3,4-ethylenedioxythiophene) (PEDOT) and the water-soluble PEDOT-PSS being the most successful commercially used conducting polymers. The polyselenophene family together with poly(3,4-ethylenedioxyselenophene) (PEDOS) and its derivatives have been shown to have slightly different properties compared to these of polythiophene and PEDOT because of their different electron donating characters, aromaticities (selenophene vs thiophene), oxidation potentials, electronegativities, and polarizabilities (Se vs S). As a result, the polyselenophenes, especially PEDOS and its derivatives, show a lower band gap and higher-lying highest occupied molecular orbital (HOMO) levels compared with those of thiophene and the PEDOT family. In an organic materials context, the PEDOS family offers some advantages over PEDOT derivatives. This Account draws on computational studies, synthetic methods, electrochemical polymerizations, chemical polymerizations, and the materials properties of PEDOS and its derivatives to demonstrate the importance of these novel materials, which lie at the frontier of conducting polymer research. In particular, we show that (i) PEDOS derivatives have a lower band gap (about 0.2 eV) than the corresponding PEDOT derivatives. Consequently, PEDOS derivatives can absorb the solar spectrum more efficiently compared to PEDOT derivatives and the properties of optoelectronic devices based on neutral and doped PEDOS should be somewhat different from these of PEDOT. (ii) EDOS derivatives have a greater tendency to undergo electrochemical polymerization compared to EDOT derivatives and offer stable and smooth polymer films. (iii) The PEDOS backbone is more rigid than the PEDOT backbone. (iv) PEDOS derivatives are excellent electrochromic materials with high transparency, and have higher contrast ratio and coloration efficiency. (v) The PEDOS/C electrode offers better control over the formation and size of nanoparticles through Se···Pt interactions compared with the PEDOT/C electrode. In addition to this, we summarize the synthesis, electrochemical polymerization, materials properties, and computational studies of fused polyselenophene analogues, namely, poly(cyclopenta[c]selenophene), and a series of low band gap thieno- or selenolo-fused polyselenophenes and selenolo-fused polythiophene. Additionally, we discuss oxidative and solid state polymerization to obtain conducting PEDOS, and its derivatives, and made throughout comparison with S-analogue where applicable. We found that EDOS-based derivatives have a greater tendency toward solid state polymerization and working at a temperature about 20 °C lower than that required for EDOT-based compounds. Our results demonstrate the utility of EDOS unit for generating promising materials PEDOS and its derivatives for electronic devices. Consequently, EDOS structure is the basis for many functionalized polymers and copolymers with tunable optoelectronic and redox properties. These interesting properties, which include high conductivity, lower band gap, rigidity, multicolor electrochromism, and rapid redox switching, allow them to be used in a variety of electronic applications.

9.
Phys Chem Chem Phys ; 17(4): 2335-8, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25504144

RESUMO

Two diacetylide-triphenylamine hole-transport materials (HTM) with varying redox potential have been applied in planar junction TiO2-[CH3NH3]PbI3-xClx solar cells leading to high power-conversion efficiencies up to 8.8%. More positive oxidation potential of the HTM gives higher VOC and lower JSC illustrating the role of matching energy levels, however both HTMs gave efficient cells despite a difference of 0.44 V in their redox potentials.

10.
Phys Chem Chem Phys ; 16(48): 27043-52, 2014 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-25382728

RESUMO

For the first time, we here propose a green methodology to modify a low bandgap polymer for highly efficient solar cells using atmospheric pressure plasma jet or soft plasma operating on different feeding gases (air, Ar and N2). The physical properties of the modified polymer were investigated using conductivity measurements, UV-visible spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammograms, atomic force microscopy, cathodoluminescence and confocal Raman spectroscopy. Further, we examined the variation of the work function of the polymer before and after plasma treatment using a γ-focused ion beam. Additionally, photovoltaic cells based on the plasma-modified polymer having ITO/PEDOT:PSS/PHVTT (with or without plasma modification):PC71BM/LiF/Al configuration were fabricated and then characterized. We found that the power conversion efficiency (PCE) of the plasma-modified polymer increased dramatically as compared to the control polymer (without plasma treatment). PCE of the control polymer was found to be 4.11%, while after air, Ar and N2 gas plasma treatment the polymer showed PCEs of 4.85%, 4.87% and 5.14% respectively. Thus, plasma treatment not only alters the surface properties, but also modifies the bulk properties (changes in HOMO and LUMO bandgap level). Hence, this work provides new dimensions to explore more about plasma and polymer chemistry.


Assuntos
Fontes de Energia Elétrica , Gases em Plasma/química , Polímeros/química , Energia Solar , Tiazóis/química , Desenho de Equipamento , Química Verde
11.
Phys Chem Chem Phys ; 16(34): 18375-82, 2014 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-25070082

RESUMO

In this work, we demonstrated the action of nanosecond pulsed plasma (NPP) on the generation of nitric oxide (NO) from the non-enzymatic pathway and on the modification of graphite oxide (GO) sheets to increase polymer solar cells (PSCs) efficiency. NO is an important signal and an effector molecule in animals, which is generated from the enzyme-catalyzed oxidation of L-arginine to NO and L-citrulline. Hence, L-arginine is an important biological precursor for NO formation. Therefore, we developed a new non-enzymatic pathway for the formation of NO and L-citrulline using NPP and characterized the pathway using NO detection kit, NMR, liquid chromatography/capillary electrophoresis-mass spectrometry (LC/CE-MS) for both quantitative and qualitative bioanalysis. We then synthesized and modified the functional groups of GO using NPP, and it was characterised by X-ray photoelectron spectroscopy (XPS), confocal Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) imaging, cathodoluminescence (CL) and work function using γ-FIB. Further, we also tested the power conversion efficiency of the PSCs devices with modified GO that is similar to the one obtained with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) as HTL. This work is perceived to have great implications for inexpensive and efficient methodology for NO generation and modification of GO, which are applicable in materials from nanomaterials to biomolecules.


Assuntos
Arginina/síntese química , Fontes de Energia Elétrica , Grafite/química , Óxido Nítrico/síntese química , Gases em Plasma/química , Energia Solar , Enzimas/química , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais , Óxidos/química
12.
Cureus ; 16(3): e56676, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38646342

RESUMO

Van Neck-Odelberg disease, also known as ischiopubic osteochondritis, is a rare cause of buttock or groin pain in the pediatric age group. The challenge in its diagnosis is due to its radiologic similarity. Ischiopubic synchondrosis occurs in childhood and is seen before the fusion of the pubis and ischium. With the advancement of age toward skeletal maturity, ischiopubic synchondrosis reduces in size and gradually vanishes due to synostosis or bony union. Here, we report the case of a 13-year-old girl who came to our outpatient department with complaints of bilateral groin pain for one year. After a thorough evaluation, she was diagnosed with a case of bilateral Van Neck-Odelberg disease, or ischiopubic osteochondritis, and conservative management was planned. Closure of ischiopubic synchondrosis varies with age and is usually finished before puberty. In a typical scenario, such fusion of the pubis and ischium does not lead to any clinical symptoms. However, in a few instances, children may experience some pain in the groin, hip, or gluteal region, which results in restricted movements at the hip joint and can lead to limping while walking. Van Neck-Odelberg disease is rare in children, causing pain in the groin region. As it is a rare condition, diagnosis is often missed. The radiological appearance suggests many differential diagnoses, such as a stress fracture, neoplasm, or infection. Prompt diagnosis and treatment can relieve the symptoms.

13.
Cureus ; 16(2): e54648, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38524028

RESUMO

Staphylococcus aureus infection is the most common cause of osteomyelitis. Over 100,000 fungal species have been described; only 150 are pathogenic to humans. These opportunistic infections frequently enter the body due to a decrease in host defense or through an invasive gateway, such as a dental extraction or skin discontinuity due to trauma. Symptoms and radiological examination often mimic those of other etiologies, which can lead to substantial delays in treatment. Our case is a 13-year-old healthy boy with no history of immune incompetency who presented to us with complaints of pain and swelling over his left ankle and leg with an on-and-off history of fever for 15 days. Based on his history and examination, he is diagnosed as having sub-acute osteomyelitis of the distal tibia with septic arthritis. The bacterial culture has no growth; however, the potassium hydroxide mount came positive for fungal elements having hyphae and pseudohyphae, and the fungal culture came positive for Candida. Management of fungal infections is challenging as they have infrequent involvement in bones. Fungal osteomyelitis is considered a rare entity in the literature, and the current case is studied for the management and diagnosis of a rare variant of osteomyelitis in the pediatric population. The treatment guidelines vary based on the identified organism and the duration of treatment. Debridement of fungal osteomyelitis or septic arthritis includes removing sinus tracts, evaluation for squamous cell carcinoma, bony and soft-tissue debridement, and antibiotic or antifungal bead placement. The spectrum of osteomyelitis ranges from Staphylococcus aureus organisms to tumors; therefore, it is necessary to investigate every spectrum of the disease, and fungal infections should be considered differential even though they are a rare entity. Early diagnosis, surgical debridement, and proper antifungal treatment based on fungal species lead to better clinical outcomes and results.

14.
Cureus ; 16(6): e61487, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38952596

RESUMO

INTRODUCTION: Congenital talipes equinovarus (CTEV) is a congenital deformity that requires weekly visits to the hospital for manipulation and corrective cast application, followed by an intensive bracing regimen requiring multiple visits to the hospital spread over the years. Parents of children with clubfoot are known to undergo a range of negative emotions. The objective of this study was to identify the prevalence of depression and the factors associated with depression in parents of children with idiopathic CTEV. METHODS: This cross-sectional study consecutively enrolled 190 parents of children with idiopathic CTEV undergoing treatment at King George Medical University. Parents with conditions that preclude the assessment of mental status were not included. These conditions include a history of head injury or psychiatric illness, parents with ongoing treatment of psychiatric illness, ongoing chronic illness, chronic neurological disease, and parents with clinically established intellectual disability. Information was recorded on certain parent-related characteristics and certain child-related characteristics. Parent-related information included age and sex of the parent, religion, area of residence, number of children in the family, degree of perceived social support (using the Multidimensional Scale of Perceived Social Support, MSPSS), level of education, socio-economic status, depression subscale score of DASS 21 (Depression, Depression Anxiety, and Stress Scale -21), chronic pain (visual analogue scale, VAS), family history of clubfoot or depression, and level of stress caused by a major life event during the past year using the Presumptive Stressful Life Event Scale (PSLES). Child-related information included the sex of the child, phase of treatment (casting or bracing), limb involvement (unilateral or bilateral), relapse of the deformity, and Pirani score of the deformity. Bivariate analysis and logistic regression were used to identify factors associated with a score ≥10 on the depression subscale of DASS 21. RESULTS: One hundred forty-five subjects were males (76.3%). The mean age of the enrolled parents was 28.47±4.89 years. The mean score on the depression subscale of DASS-21 was 4.87±6.3. Thirty-two parents (16.8%) had a score of ≥10 on the depression subscale of the DASS-21. On bivariate analysis, female sex, being Hindu, having studied up to class 12th, relapse, MSPSS score, and PSLES score were found to be associated with a score ≥10 on the depression subscale of the DASS-21. On logistic regression, female sex, lack of graduate education and above, and MSPSS scores were found to be significantly associated with a score of ≥10 on the depression subscale of the DASS 21 score. CONCLUSION: The prevalence of depression in parents of children with idiopathic clubfoot was 16.8%. Female gender, lack of college education, and the level of perceived social support (MSPSS) are independently associated with a score ≥10 on the depression subscale of DASS 21. We recommend screening parents of children with clubfoot and referring those with abnormal scores to a psychiatrist for a confirmed diagnosis.

15.
Cureus ; 16(3): e57274, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38686237

RESUMO

INTRODUCTION: Legg-Calve-Perthes disease (LCPD) is a disorder involving the hips in young children of preschool and school-going age groups, more common in 4-8 years. The insufficient blood supply to the femoral head is the main reason behind various etiologic theories. Multiple factors affect the natural progression of the disease. The natural progression of the disease involves early avascular necrosis, fragmentation, reconstitution, and healed stages. In the fragmentation stage, the bony epiphysis begins to fragment, and the subchondral radiolucent zone (crescent sign) is the result of a subchondral stress fracture, which later on determines the extent of a necrotic fragment of the femoral head. These changes later contribute to changes in the shape of the femur head and the extent of deformity. As vitamin D plays a vital role in the onset of the fragmentation stage, we conducted a study to assess the effect of vitamin D deficiency as a risk factor for early fragmentation in Legg-Calve-Perthes disease. METHODS: In our study, 50 patients aged 4-12 years were examined over three years and classified according to Catterall and Herring's lateral pillar classification; the length of the fragmentation stage and the vitamin D level were considered. A vitamin D level of less than 20 ng/mL was labeled as the deficient group, 20-30 ng/mL as the insufficient group, and more than 30 ng/mL as the sufficient (normal) group. RESULTS: The critical fragmentation stage was significantly longer (more than 12 months) in vitamin D deficiency (34%), leading to a higher risk of deformity and extrusion of the femoral head, which led to higher rates of surgical intervention and containment procedures. CONCLUSION: The fragmentation stage is critical in the course of LCPD. Vitamin D levels play a vital role in predicting the prognostic of LCPD, and it should be measured in all patients of LCPD. Patients with normal vitamin D levels have a comparatively shorter fragmentation stage duration than patients with insufficient or deficient levels, leading to a lesser duration of femoral head damage.

16.
J Clin Orthop Trauma ; 39: 102144, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36923448

RESUMO

Background: Due to various policy and health infrastructure issues, it is not uncommon to present developmental dysplasia of hip(DDH) at walking-age in India. The purpose of this study was retrospective analysis of operated cases of walking-age DDH with "inferior over-reduction". Methods: "Inferior over-reduction" was defined as break in the Shenton's arc inferiorly in an operated hip which otherwise appears reduced. After Ethical Committee approval, we searched children operated for walking-age DDH. Children suggestive of syndromic association were excluded. We collected demographic data, follow-up, procedures performed, inferior over-reduction and complications. The IHDI grade, Acetabular Index(AI), Smith's ratio for superior (h/b) & lateral displacement(c/b) of femur, and clinical outcome (Modified McKay criteria) were evaluated. The outcomes of cases with inferior over-reduction(Group A) were compared with those without(Group B). Results: 42 patients with average follow-up of 23 months were enrolled. 21 hips belonged to Group A. By 6 months follow up, all these cases recovered. On comparison of Smith's ratio, group A had significantly higher c/b for the operated hip at 3-month follow-up(p < 0.05). Patients undergoing acetabuloplasty had significantly lower c/b versus all other groups(p < 0.05). Correlation between h/b or c/b with age did not show any significant finding. 15 cases in group A and 14 cases in group B had excellent outcome as per modified McKay's criteria. None of the patients had inferior over-reduction, inferior or obturator dislocation at final follow-up. Three patients with group B had re-dislocation with poor outcome. we recorded 3 hips with AVN (7%). Conclusions: This study highlights that after OR of walking-age DDH, the inferior over-reduction may be noted in as much as 50% of the cases. However, this is transient, and all cases recover by the 6 months follow up. There is no significant difference between group A & B in functional outcome, AVN rate. Long-term studies are required to see outcome differences between two groups.

17.
Cureus ; 15(10): e47717, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38022147

RESUMO

INTRODUCTION: The septic arthritis of the hip (SAH) is one of the most common musculoskeletal infections occurring in pediatric populations requiring urgent intervention. This study discusses the myriad of clinical and radiological presentations of late-presenting SAH in children and the outcomes of surgical management. METHODS: After ethical approval, we did retrospective reviews of children treated for late-presenting SAH (after five days of symptoms). We excluded late cases with established sequelae. We recorded age, duration of symptoms, clinical evaluation, and radiographs. We evaluated the final results clinically and radiologically. RESULTS: Twenty-four patients with 25 hips were eligible for evaluation. At presentation, all had decreased or painful hip movements, but none had a fever. Radiographs revealed the following changes: hip dislocation (four), capital femoral slip (seven), proximal femur/neck osteomyelitis (six), pathological fractured neck femur (two), iliac osteomyelitis (two), and early arthritic changes (two). Hip arthrotomy was done in all cases. Frank pus was found in 21 (84%) cases. Cases with capital slip and fractured neck femur required fixation with two smooth K-wires. Methicillin-resistant Staphylococcus aureus (MRSA) was isolated in three patients and tuberculosis in two cases. Clinical outcomes showed 14 patients with poor outcomes, eight with fair, and two with good. Avascular necrosis (AVN) of the femoral head was noted in 14 hips and complete femoral head resorption in nine. CONCLUSIONS: The late-presenting SAH in children has a myriad of presentations including dislocation and capital slip with unsatisfactory outcome. However, ongoing local infective processes may necessitate debridement. With limited salvage options available at the sequelae stage, awareness and training for early diagnosis and treatment may be the best way to improve the scenario. We recommend future multicenter randomized studies of predictive factors and indications of arthrotomy in late presenters.

18.
J Orthop Case Rep ; 12(6): 91-94, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37065526

RESUMO

Introduction: It is very common for pediatric orthopedic surgeon to encounter developmental dysplasia of hip (DDH) in walking age, especially in developing countries. The conservative options of management are almost over by this age and most require open reduction (OR) with various adjunct procedures. The most preferred approach for OR in this age group is anterior Smith-Peterson approach to hip joint. These neglected cases also require femoral shortening ± derotation osteotomy and acetabuloplasty. Case Report: In this surgical video technique, we demonstrate OR + femoral shortening and derotation osteotomy and acetabuloplasty, step by step, in a neglected, walking age DDH in a 3-year-old child. We hope that the detailed demonstration and tricks at various surgical steps will benefit our readers and viewers. Conclusion: Step-wise surgical execution as per demonstrated technique makes the procedure easily reproducible with fairly good outcomes. In this case example, with demonstrated surgical technique, we were able to achieve a good outcome at short-term follow-up.

19.
J Clin Orthop Trauma ; 24: 101711, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34815627

RESUMO

PURPOSE: The COVID-19 pandemic had serious impact on health care sector. During reprioritisation of the services, elective and non-emergency procedures were suspended, with gradual resumption of services after lockdown was over. In this study we assessed the impact of pandemic on our clubfoot program at a tertiary care institute. Also, we discussed the future challenges and strategies to re-start our clubfoot program. METHODS: Data was collected retrospectively regarding registrations, demography and procedures done at our clubfoot centre. Study period was 25 March to 31 December 2020 and it was compared with same duration from previous years 2019 and 2018. After the data analysis, the findings were discussed on departmental committee meeting, future challenges were considered and strategies were charted out for re-establishing the clubfoot program at our Institute. RESULTS: When compared to previous year, we noted 46% decline in paediatric outpatient registrations and 60% decline in new clubfoot registrations at our centre. The clubfoot follow-up visits reduced by 30% in the pandemic year 2020. 80% of clubfoot registrations were local residents during pandemic year, which was 54%, 58% in year 2019 and 2018 respectively. The percentage of neglected cases remained stable, however, share of relapse cases increased during pandemic year. There was 80% decline in number of tenotomies and 90% decline in other clubfoot surgeries performed during pandemic year 2020 compared to year 2019. CONCLUSION: COVID-19 pandemic had definite disruptive impact on our clubfoot program. With decreased new registrations, follow-up visits and increased relapses, we anticipate a significant increase in clubfoot cases in need of casting & treatment. To deal with pent-up demand and an anticipated wave of relapse and neglected clubfoot cases, we have proposed strategies to re-establish clubfoot program in post-pandemic new-normal. We hope these will prepare us for any adversaries we face.

20.
Indian J Orthop ; 56(12): 2182-2192, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36507217

RESUMO

Purpose: Above-knee casts pose a major challenge in the day-to-day activities among walking age clubfoot patients due to complete restriction of knee movement. This current study investigates the effectiveness of below-knee casts compared to above-knee casts for managing walking age clubfoot deformity. Methods: After approval from the institutional ethical committee, we enrolled walking age clubfoot patients for deformity correction through corrective manipulation and casting through below-knee casts over 2 years. The corrective manipulation was performed using the Ponseti technique. The patients were followed for a minimum of 2 years period. To compare the effectiveness of below-knee casts over above-knee casts, we enrolled equal numbers of walking age clubfeet matched for age and gender. We compared the two groups in terms of initial and post-correction Dimeglio scores, individual deformities corrections (maximum ankle dorsiflexion, heel varus correction, foot abduction), failure rates, relapses, and complication rates. Results: 56 patients with 80 clubfeet with a mean follow-up of 39.98 months were considered for the final analysis. There were 29 patients in the below-knee cast group and 27 in the above-knee cast group, with 40 clubfeet each. The patients in the above-knee casting group had significantly better post-correction Dimeglio scores and individual deformity components corrections than the below-knee cast group. There were nil failures in the above-knee casting group and 7.5% in the below-knee cast group. The relapse rate was 15% in both groups, with none requiring any extensive soft tissue procedure. We did not encounter any major complications during the treatment and follow-up. Conclusion: The deformity correction and maintenance are suboptimal with the below-knee casts. Therefore, above-knee casts should be the preferred management modality for correction of walking age clubfoot deformities.

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