Cubitus Valgus with Tardy Ulnar Nerve Palsy - Functional Outcome of Milch Osteotomy without Anterior Transposition of Ulnar Nerve

Introduction:

To assess the results of Milch osteotomy in terms of deformity correction and functional outcome in the absence of ulnar nerve transposition.

Material and Methods:

Nine patients with cubitus valgus deformity greater than 20° with tardy ulnar nerve palsy (TUNP) operated between 2012 and 2017 were evaluated. Correction by Milch osteotomy and fixation was done in each case, without osteosynthesis of the non-union lateral condyle humerus or transposition of the ulnar nerve. At one year post-operatively, carrying angle, elbow function (Mayo Elbow Performance Score) and ulnar nerve symptoms were assessed.

Results:

The mean carrying angle pre-operatively was 30.8° on the affected side which improved to a mean of 8.3° postoperatively with an average correction of 22.5°. The mean elbow flexion pre-operatively was 129.4° which improved to 133.3° post-operatively. The mean preoperative MEP score was 76.7 which improved to a mean of 92.2 post-operatively (p < 0.01). TUNP recovered completely in all the patients.

Conclusion:

Milch osteotomy is an effective procedure for cubitus valgus deformity correction and its associated tardy ulnar nerve palsy without a decrease in elbow ROM. Correction of even severe valgus deformities without concurrent anterior transposition of the ulnar nerve is likely to improve ulnar nerve symptoms.

Facile Synthesis of Bio-Templated Tubular Co₃O₄ Microstructure and Its Electrochemical Performance in Aqueous Electrolytes

Template-assisted facile synthesis of tubular Co₃O₄ microstructures and its electrochemical performance was studied to understand its use as a potential electrode material for supercapacitors. Tubular porous Co₃O₄ microstructures were synthesized using cotton fibers as bio-template. The as-obtained templated Co₃O₄ structure inherits the morphology and microstructure of cotton fiber. The electrochemical performance of the electrode made up of tubular Co₃O₄ structure was evaluated in 3 M KOH, NaOH, and LiOH aqueous electrolytes. The large-surface-area of tubular Co₃O₄ microstructure has a noticeable pseudocapacitive performance with a capacitance of 401 F/g at 1 A/g and 828 F/g at 2 mV/s, a Coulombic efficiency averaging ~100%, and excellent cycling stability with capacitance retention of about 80% after 5,000 cycles. Overall, the tubular Co₃O₄ microstructure displayed superior electrochemical performance in 3 M KOH electrolyte with peak power density reaching 5,500 W/kg and energy density exceeding 22 Wh/kg. The superior performance of tubular Co₃O₄ microstructure electrode is attributed to its high surface area and adequate pore volume distribution, which allows effective redox reaction and diffusion of hydrated ions. The facile synthesis method can be adapted for preparing various metal oxide microstructures for possible applications in catalysis, electrochemical, sensors, and fuel cells applications.

Influence of Urea on the Synthesis of NiCo₂O₄ Nanostructure: Morphological and Electrochemical Studies

The widespread use of miniature electronic devices calls for energy-dense storage strategies. The supercapacitor-based energy storage devices with high areal capacitance are desired energy storage alternative. It is still a challenge to fabricate supercapacitor-based energy devices with consistent performance. The porous metal oxides with large areal capacitance are desired materials for electrode, but there exists a limited understanding of the influence of synthesis parameters on microstructural properties, which largely govern their electrochemical performance. In the present work, hierarchal spinel nickel cobaltite (NiCo₂O₄) nanostructures were synthesized in the presence of the varying amount of hydrolyzing agent via a simple hydrothermal method coupled with a simple post-annealing process. This work focuses on understanding the influence of hydrolyzing agent in controlling the microstructure and hence ensuing electrochemical properties of the NiCo₂O₄ based electrode. Based on the urea hydrolyzing content, the as synthesized NiCo₂O₄ nanostructure varied from the rod, plate to nanoflower. The mesoporous nanostructures, with urea content 1.49 gm, exhibit a sizeable BJH surface area (79.2 m² g^-1) and high mesopore volume (0.140 cm³ g^-1). Remarkably, the NiCo₂O₄ nanoflower shows high specific capacitance of 3143.451 F/g at 2 mV/s scan rate, 1264.5 F/g at 1 A/g current density, energy density of 56 Wh/kg and power density of 8,400 W/kg in 3 M KOH electrolyte. The capacitance loss after 5000 cycles is 48% at the current density of 10 A/g, indicating their excellent cycling stability. The impressive electrocatalytic activity is largely ascribed to the high intrinsic electronic conductivity, superior mesoporous nanostructures and rich surface Ni active species of the NiCo₂O₄ materials, which can largely boost the interfacial electroactive sites and charge transfer rates indicating promising applications as electrodes in future supercapacitors.

Spiral T1 Spin-Echo for Routine Postcontrast Brain MRI Exams: A Multicenter Multireader Clinical Evaluation

BACKGROUND AND PURPOSE

Spiral MR imaging has several advantages compared with Cartesian MR imaging that can be leveraged for added clinical value. A multicenter multireader study was designed to compare spiral with standard-of-care Cartesian postcontrast structural brain MR imaging on the basis of relative performance in 10 metrics of image quality, artifact prevalence, and diagnostic benefit.

MATERIALS AND METHODS

Seven clinical sites acquired 88 total subjects. For each subject, sites acquired 2 postcontrast MR imaging scans: a spiral 2D T1 spin-echo, and 1 of 4 routine Cartesian 2D T1 spin-echo/TSE scans (fully sampled spin-echo at 3T, 1.5T, partial Fourier, TSE). The spiral acquisition matched the Cartesian scan for scan time, geometry, and contrast. Nine neuroradiologists independently reviewed each subject, with the matching pair of spiral and Cartesian scans compared side-by-side, and scored on 10 image-quality metrics (5-point Likert scale) focused on intracranial assessment. The Wilcoxon signed rank test evaluated relative performance of spiral versus Cartesian, while the Kruskal-Wallis test assessed interprotocol differences.

RESULTS

Spiral was superior to Cartesian in 7 of 10 metrics (flow artifact mitigation, SNR, GM/WM contrast, image sharpness, lesion conspicuity, preference for diagnosing abnormal enhancement, and overall intracranial image quality), comparable in 1 of 10 metrics (motion artifacts), and inferior in 2 of 10 metrics (susceptibility artifacts, overall extracranial image quality) related to magnetic susceptibility (P < .05). Interprotocol comparison confirmed relatively higher SNR and GM/WM contrast for partial Fourier and TSE protocol groups, respectively (P < .05).

CONCLUSIONS

Spiral 2D T1 spin-echo for routine structural brain MR imaging is feasible in the clinic with conventional scanners and was preferred by neuroradiologists for overall postcontrast intracranial evaluation.

The Impact of HIV-1 Drug Escape on the Global Treatment Landscape

The rising prevalence of HIV drug resistance (HIVDR) could threaten gains made in combating the HIV epidemic and compromise the 90-90-90 target proposed by United Nations Programme on HIV/AIDS (UNAIDS) to have achieved virological suppression in 90% of all persons receiving antiretroviral therapy (ART) by the year 2020. HIVDR has implications for the persistence of HIV, the selection of current and future ART drug regimens, and strategies of vaccine and cure development. Focusing on drug classes that are in clinical use, this Review critically summarizes what is known about the mechanisms the virus utilizes to escape drug control. Armed with this knowledge, strategies to limit the expansion of HIVDR are proposed.

A clinicopathological study of upper aerodigestive tract cancers

Background

The upper aerodigestive tract (UAT) includes the nose and paranasal sinuses, oral cavity, pharynx, larynx, and salivary glands. Cancers of the UAT constitute approximately 4% of all malignancies. In this study, the varied nature of the UAT cancers was studied to find out their incidence, etiology, and clinicopathological correlations.

Materials and Methods

This prospective, observational, and clinicopathological study was conducted on 100 patients who were presented at outdoor in the Department of ENT, Government Medical College/Rajindra Hospital, Patiala, Punjab, India, from October 2016 to October 2018. Proven cases of UAT cancers were taken up and reviewed to gather data on multiple clinicopathological variables, such as age, sex, predisposing factors, and site of pathology. Histopathological differentiation was noted after conducting a biopsy.

Results

Most patients of UAT cancers were in the age group of 40-70 years. Maximum incidence was among males (82%) compared to females (28%). The most common predisposing factor was alcohol + smoking (28%), followed by alcohol + chewing tobacco (25%). The most common symptom in the oral cavity was ulcer and odynophagia (38%) each. In oropharyngeal cancers, dysphagia (92%) was the most common symptom. In laryngeal cancers, dyspnea (68%) and hoarseness of voice (32%) were the most common. The most common site involved in UAT cancers was the oral cavity (31%), followed by oropharynx (28%), larynx (22%), hypopharynx (7%), and salivary gland (5%). The most common histopathological type was squamous cell carcinoma (SCC) (90%). Most of the ulceroproliferative and exophytic growth was moderately differentiated SCC on histopathology.

Conclusion

Studies are essential for education and awareness aimed at reducing exposure to habit-forming substances.

Tuberculosis infection and disease in people living with HIV in countries with low tuberculosis incidence

In countries with low tuberculosis (TB) incidence, TB is concentrated in vulnerable populations, including people living with the human immunodeficiency virus (PLHIV), who have a substantially greater risk of TB than people without HIV. We searched PubMed, EMBASE and Web of Science for studies evaluating the risk factors for latent tuberculous infection (LTBI) or active TB in PLHIV in countries with TB incidence 10 per 100 000 population. Due to the number of risk factors evaluated and heterogeneity in study designs, we present summary data and a narrative synthesis. We included 45 studies: 17 reported data on the risk factors for LTBI and 32 on active TB. Black, Asian or Hispanic ethnicity, birth or long-term residence in a country with high TB incidence, and HIV acquisition via injecting drug use (IDU) or heterosexual sex were strong predictors of both LTBI and active TB. History of contact, a greater degree of immunosuppression at diagnosis or higher viral load increased the TB risk. Early HIV diagnosis to allow timely initiation of antiretroviral therapy is essential for the prevention of TB in PLHIV. Screening and treating PLHIV for LTBI to reduce the risk of progression to active TB disease should also be considered to further reduce the burden of active TB in low TB incidence settings. Research to support the expansion of TB and HIV prevention and treatment globally is essential to eliminate TB in low-incidence settings.

Physical Properties and Theoretical Study of NixCo3-xO₄ (0 ≤ x ≤ 1.5) Nanostructures as High-Performance Electrode Materials for Supercapacitors

Study evaluates the electrochemical performance of off-stoichiometric Ni_xCo_3-xO₄ compounds. The off-stoichiometric samples were prepared via hydrothermal technique by systematically varying Co/Ni molar ratio. Physical and electrochemical properties of Ni_xCo_3-xO₄ were observed to be stoichiometry dependent. The increase in Ni/Co ratio in Ni_xCo_3-xO₄ leads to the morphological transformation from fibrous bundles to urchin like nanospheres with a concomitant increase in the surface area reaching up to 132 m2/g. The optimal specific capacitance of 225 F/g at a current density of 1 A/g and 524 F/g at 10 mV/s scan rate was observed of x 1.0 sample, with an increased retention capacity ∼120% measured at 2 A/g current density. The hybrid density functional theory (DFT) calculations of the electronic density of states identified Ni_1.0Co₂O₄ with optimal band-gap of 2.38 eV with an expectation of displaying higher electrocapacitive performance. Experimentally, Ni_0.92Co_2.08O₄ displayed superior electrocapacitive performance among all Ni/Co ratio in Ni_xCo_3-xO₄. The DFT study also predicted Ni preference to the octahedral site, which is in-line with the observed increase in ferromagnetic nature, decreased lattice parameter, and increased structural disorder with increasing Ni/Co ratio. The improved electrochemical performance of Ni_xCo_3-xO₄ (x > 0) is attributed to the mesoporous hierarchical structure, with a high electroactive surface which can effectively improve structural stability, and reduce the ionic and electron diffusion length. Compared to the pure Co₃O₄, the reduction of Co content in Ni_xCo_3-xO₄ is desired due to the high cost and toxicity of Co element.

Porous carbons derived from polyethylene terephthalate (PET) waste for CO2 capture studies

Oxygen augmented carbon adsorbent has been developed using polyethylene terephthalate (PET) waste by first carbonizing at different temperatures (500-800 °C) and then chemically activating using different ratios of KOH: PET (mass ratio 1 to 4). The textural characterization divulges the effect of activation in terms of the development of the high surface area and micropore volume of 1690 m² g^-1 and 0.78 cm³ g^-1 respectively, for the optimum sample (PET-3-700). Elemental analysis of PET-3-700 illustrates the presence of 34.33% oxygen and XPS results confirmed the occurrence of oxygen moieties which enhance the basicity of the adsorbent and promote CO₂ capture. The CO₂ adsorption capacity of prepared carbons was determined thermogravimetrically under dynamic conditions, at different concentrations of CO₂ (6-100%) and temperatures. The maximum CO₂ uptake capacity of 2.31 mmol g^-1 was exhibited by PET-3-700 at an adsorption temperature of 30 °C under 100% pure CO₂ flow. Four adsorption-desorption cycles corroborate almost complete regenerability of the prepared adsorbent. Adsorption kinetics at all adsorption conditions was described best by fractional order kinetic model. Freundlich isotherm fit indicates the surface of adsorbent being heterogeneous and low values of isosteric heat shows physisorption behavior of the process. Negative values of thermodynamic parameters indicate exothermic and feasible nature of adsorption process.

EEG Neurofeedback Training in Children With Attention Deficit/Hyperactivity Disorder: A Cognitive and Behavioral Outcome Study

BACKGROUND

Attention deficit/hyperactivity disorder (ADHD) is a highly prevalent childhood disorder with symptoms of inattention, impulsivity, and hyperactivity. EEG neurofeedback training (NFT) is a new intervention modality based on operant conditioning of brain activity, which helps reduce symptoms of ADHD in children.

METHODS AND PROCEDURES

To examine the efficacy of NFT in children with ADHD, an experimental longitudinal design with pre-post comparison was adopted. A total of 30 children in the age range of 6 to 12 years diagnosed as ADHD with or without comorbid conditions were assigned to treatment group (TG; n = 15) and treatment as usual group (TAU; n = 15). TG received EEG-NFT along with routine clinical management and TAU received routine clinical management alone. Forty sessions of theta/beta NFT at the C3 scalp location, 3 to 4 sessions in a week for a period of 3.5 to 5 months were given to children in TG. Children were screened using sociodemographic data and Binet-Kamat test of intelligence. Pre-and postassessment tools were neuropsychological tests and behavioral scales. Follow-up was carried out on 8 children in TG using parent-rated behavioral measures.

RESULTS

Improvement was reported in TG on cognitive functions (sustained attention, verbal working memory, and response inhibition), parent- and teacher-rated behavior problems and on academic performance rated by teachers. Follow-up of children who received NFT showed sustained improvement in ADHD symptoms when assessed 6 months after receiving NFT.

CONCLUSION

The present study suggests that NFT is an effective method to enhance cognitive deficits and helps reduce ADHD symptoms and behavior problems. Consequently, academic performance was found to be improved in children with ADHD. Improvement in ADHD symptoms induced by NFT were maintained at 6-month follow-up in children with ADHD.

Refurbishment of an Au-coated toroidal mirror by capacitively coupled RF plasma discharge

Deposition of synchrotron-radiation-induced carbon contamination on beamline optics causes their performance to deteriorate, especially near the carbon K edge. The photon flux losses due to carbon contamination have spurred researchers to search for a suitable decontamination technique to restore the optical surface and retain its performance. Several in situ and ex situ refurbishing strategies for beamline optics are still under development to solve this serious issue. In this work, the carbon contamination is removed from a large (340 mm × 60 mm) Au-coated toroidal mirror surface using a capacitively coupled low-pressure RF plasma. Before and after RF plasma cleaning, the mirror was characterized by Raman spectroscopy, soft X-ray reflectivity (SXR) and atomic force microscopy (AFM) techniques. The Raman spectra of the contaminated mirror clearly show the G (1575-1590 cm^-1) and D (1362-1380 cm^-1) bands of graphitic carbon. The SXR curve of the contaminated mirror shows a clear dip near the critical momentum transfer of carbon, indicating the presence of carbon contamination on the mirror surface. This dip disappears after removal of the contamination layer by RF plasma exposure. A decrease in the intensities of the CO bands is also observed by optical emission spectrometry during plasma exposure. The AFM and SXR results suggest that the root-mean-square (r.m.s.) roughness of the mirror surface does not increase after plasma exposure.

Active case finding and treatment adherence in risk groups in the tuberculosis pre-elimination era

Vulnerable populations, including homeless persons, high-risk drug and alcohol users, prison inmates and other marginalised populations, contribute a disproportionate burden of tuberculosis (TB) cases in low-incidence settings. Drivers of this disease burden include an increased risk of both TB transmission in congregate settings, and progression from infection to active disease. Late diagnosis and poor treatment completion further propagate the epidemic and fuel the acquisition of drug resistance. These groups are therefore a major priority for TB control programmes in low-incidence settings. Targeted strategies include active case finding (ACF) initiatives and interventions to improve treatment completion, both of which should be tailored to local populations. ACF usually deploys mobile X-ray unit screening, which allows sensitive, high-throughput screening with immediate availability of results. Such initiatives have been found to be effective and cost-effective, and associated with reductions in proxy measures of transmission in hard-to-reach groups. The addition of point-of-care molecular diagnostics and automated X-ray readers may further streamline the screening pathway. There is little evidence to support interventions to improve adherence among these risk groups. Such approaches include enhanced case management and directly observed treatment, while video-observed therapy (currently under evaluation) appears to be a promising tool for the future. Integrating outreach services to include both case detection and case-management interventions that share a resource infrastructure may allow cost-effectiveness to be maximised. Integrating screening and treatment for other diseases that are prevalent among targeted risk groups into TB outreach interventions may further improve cost-effectiveness. This article reviews the existing literature, and highlights priorities for further research.

Quality protein maize based muffins: influence of non-gluten proteins on batter and muffin characteristics

Quality protein maize (QPM) is nutritionally improved maize which has twice the amount of lysine and tryptophan than normal maize. The present study evaluated the effect of different proteins namely egg white proteins (EWP), casein, whey protein isolate, soy protein isolate (SPI) on characteristics of gluten free QPM based muffins. QPM muffins without any added protein served as control and muffins prepared using wheat and EWP served as reference. Effect of addition of different proteins on pasting properties revealed that the thermal stability of QPM flour increased as indicated by decrease in breakdown viscosity. The effect of added proteins on QPM muffin-making properties was evaluated for rheology of batter and physicochemical, texture, color and sensory characteristics of muffins. Dynamic rheology showed that storage modulus (G') and loss modulus (G″) of batter with SPI was the highest while batter with EWP showed lowest value. QPM-EWP muffins were softer, chewy and springier and had more specific volume than control muffins and were comparable to reference muffins. Inclusion of all proteins increased L* values (lightness) and decreased a* (redness/greenness) and b* (yellow/blueness) values of QPM based muffins. Sensory analysis revealed that gluten free QPM muffin prepared from EWP were acceptable with a sensory score of 7.97 which was comparable to reference muffins (8.03).

Development of the R263K Mutation to Dolutegravir in an HIV-1 Subtype D Virus Harboring 3 Class-Drug Resistance

Dolutegravir (DTG), a second-generation integrase strand-transfer inhibitor (INSTI), is equivalent or superior to current non-nucleotide reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), and first-generation INSTI-based antiretroviral regimens (ARVs). It has the potential to make big improvements in HIV control globally and within patients. This is perhaps the most "precious" HIV drug available. The integrase mutation R263K has been observed in tissue culture experiments and in patients treated with dolutegravir monotherapy in clinical trials. Globally, adherence and monitoring may be less than optimal and therefore DTG resistance more common. This is particularly important in low-middle-income countries, where patients may remain on failing regimens for longer periods of time and accumulate drug resistance. Data on this mutation in non-subtype B infections do not exist. We describe the first report of the R263K integrase mutation in a dolutegravir-exposed subtype D-infected individual with vertically acquired HIV. We have used deep sequencing of longitudinal samples to highlight the change in resistance over time while on a failing regimen. The case highlights that poorly adherent patients should not be offered dolutegravir even as part of a combination regimen and that protease inhibitors should be used preferentially.

DNA barcoding for specific and sensitive detection of Cuminum cyminum adulteration in Bunium persicum

BACKGROUND

Bunium persicum commonly called as Kala zeera, a very high value herbaceous spice used for medicinal purposes is often adulterated with Cuminum cyminum or Safed zeera, a closely related species. Lack of distinctive morphological features makes the identification of genuine kala zeera from its adulterant difficult, the problem is even exaggerated in case of powdered material.

METHODOLOGY

Genomic DNA was extracted from all the plant materials by using CTAB-SDS method (Möller et al., 1992) with slight modifications. On the basis of reproducibility and high amplification ability, four universal barcoding loci viz. ITS2, rbcL-a, mat K and psbA-trnH and a specific locus Cum were used in the present study. The amplified PCR products were sequenced bidirectionally and assembled to obtain contigs. The sequences thus obtained were aligned using MUSCLE algorithm (Edgar, 2004) and information pertaining to conserved/ variable/ parsimony informative sites, number of transitions, transversions and Indels was obtained after analyzing the sequences.

RESULTS AND CONCLUSION

Among the tested barcoding loci, psbA-trnH has proven to be best barcode in authentication of kala zeera as its amplification and sequencing success was high and it showed the presence of polymorphic sites to detect interspecific variation. This barcode could differentiate between safed zeera and kala zeera in a single reaction, simultaneously.

Influence of the core-hole effect on optical properties of magnesium oxide (MgO) near the Mg L-edge region

The influence of the core-hole effect on optical properties of magnesium oxide (MgO) is established through experimental determination of optical constants and first-principles density functional theory studies. Optical constants (δ and β) of MgO thin film are measured in the spectral region 40-300 eV using reflectance spectroscopy techniques at the Indus-1 synchrotron radiation source. The obtained optical constants show strong core exciton features near the Mg L-edge region, causing significant mismatch with Henke's tabulated values. On comparing the experimentally obtained optical constants with Henke's tabulated values, an edge shift of ∼3.0 eV is also observed. Distinct evidence of effects of core exciton on optical constants (δ and β) in the near Mg L-edge absorption spectra are confirmed through first-principles simulations.

Comparison of Endoscopic and Histological Findings between Typical and Atypical Celiac Disease in Children

PURPOSE

Celiac disease is a common non-communicable disease with varied presentations. Purpose of this study was to find the duodeno-endoscopic features in celiac disease and to compare duodeno-endoscopic and histological findings between typical and atypical celiac disease in children.

METHODS

Hospital based observational study was conducted at Sir Padampat Mother and Child Health Institute, Jaipur from June 2015 to May 2016. Patients were selected and divided in two groups- typical and atypical celiac disease based upon the presenting symptoms. Upper gastrointestinal endoscopy and duodenal biopsy was performed for serology positive patients. Results were analysed using appropriate statistical test of significance.

RESULTS

Out of 101 enrolled patients, 47.5% were male. Age ranged from 1 to 18 years. Study showed that 54.5% were typical and 45.5% were atypical. Patients presenting with atypical symptoms were predominantly of older age group. On endoscopy, scalloping, mosaic pattern, reduced fold height and absent fold height; and in histology, advanced Marsh stage were significantly higher in the typical group.

CONCLUSION

Awareness of atypical presentations as well as duodeno-endoscopic features may have considerable practical importance for the diagnosis of celiac disease in children. Scalloping, mosaic pattern, reduced fold height and nodularity are main endoscopic markers of celiac disease in children. Endoscopic markers of duodenal mucosa may be important in early diagnosis of celiac disease, in children subjected to endoscopy for atypical presentations or indication other than suspected celiac disease.

Radiotracer investigation on the measurement of residence time distribution in an ethyl acetate reactor system with a large recycle ratio

A radiotracer investigation was carried out on the measurement of residence time distribution (RTD) of process fluid in an industrial-scale ethyl acetate reactor system, which consists of two independent reactors with recirculation and connected in series with each other. Bromine-82 as ammonium bromide was used as the radiotracer for the RTD experiments at different operating conditions. The individual reactors and the overall reactor system were modelled using physically representative phenomenological models comprising of continuously stirred tank reactors (CSTRs). The results showed that the recirculation rate considerably affected the flow mixing behaviour and mean residence time of the process fluid in the reactor system. The results also showed that there was bypassing of the fluid in the first reactor that ranged from 12% to 22% and 40% dead volume at different operating conditions, whereas the second reactor behaved closely as an ideal CSTR. The results of the investigation can be used to optimise the process parameters and design new improved reactor systems for the production of ethyl acetate.

A biomechanical study comparing proximal femur nail and proximal femur locking compression plate in fixation of reverse oblique proximal femur fractures

BACKGROUND

The reverse oblique trochanteric fractures are common fractures and its treatment poses a challenge. The purpose of this study was to compare the biomechanical parameters of the construct using proximal femoral nail (PFN) and proximal femoral locking compression plates (PFLCP) in these fractures using cadaveric specimens.

MATERIALS AND METHODS

Twenty freshly harvested cadaveric femoral specimens were randomly assigned to two groups after measuring bone mineral density, ten of which were implanted with PFN and the other ten with PFLCP. The constructs were made unstable to simulate reverse oblique trochanteric fracture (AO type 31A3.3) by removing a standard size posteromedial wedge. These constructs were tested in a computer controlled cyclic compressive loading with 200kg at a frequency of 1 cycle/s (1Hz) and test was observed for 50,000 cycles or until implant failure, whichever occurred earlier. Peak displacements were measured and analysis was done to determine axial stiffness and subsidence in axial loading.

RESULTS

All the specimens in PFN group completed 50,000 cycles and in PFLCP group, seven specimens completed 50,000 cycles. Average subsidence in PFN group was 1.24±0.22mm and in PFLCP group was 1.48±0.38mm. The average stiffness of PFN group (72.6±6.8N/mm) was significantly higher than of PFLCP group (62.4±4.9N/mm) (P=0.04). The average number of cycles sustained by PFLCP was 46634 and for PFN group was 50,000 (P=0.06).

CONCLUSION

The PFN is biomechanically superior to PFLCP in terms of axial stiffness, subsidence and number of specimens failed for the fixation of reverse oblique trochanteric fractures of femur.