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Abstract Introduction Total hip arthroplasty (THA) has revolutionized the treatment of hip joint arthritis. With the increased popularity and success of the procedure, research has focused on improving implant survival and reducing surgical complications. Optimal component orientation has been a constant focus with various philosophies proposed. Regardless of the philosophy, achieving an accurate acetabular position for each clinical scenario is crucial. In this paper, we review the recent developments in improving the accuracy and ideal positioning of the acetabular cup in routine primary THA. Methodology A review of the recent scientific literature for acetabular cup placement in primary THA was performed, with available evidence for safe zones, spinopelvic relationship, preoperative planning, patient-specific instrumentation, navigation THA and robotic THA. Conclusion Though the applicability of Lewinnek safe zones has been questioned with an improved understanding of spinopelvic relationships, its role remains in positioning the acetabular cup in a patient with normal spinopelvic alignment and mobility. Evaluation of spinopelvic relationships and accordingly adjusting acetabular anteversion and inclination can significantly reduce the incidence of dislocation in patients with a rigid spine. In using preoperative radiography, the acetabular inclination, anteversion and intraoperative pelvic position should be evaluated. With improving technology and the advent of artificial intelligence, superior and more accurate preoperative planning is possible. Patient-specific instrumentation, navigated and robotic THA have been reported to improve accuracy in acetabular cup positioning as decided preoperatively but any significant clinical advantage over conventional THA is yet to be elucidated.

Horizontal gaze palsy with progressive scoliosis (HGPPS) syndrome is a rare genetic abnormality causing cranial dysinnervation manifesting as absence of conjugate lateral eye movements, nystagmus, and scoliosis. While the genetics, imaging abnormalities, and ocular manifestations have been well described in literature, the spinal deformity has not been addressed adequately. An 11-year-old girl presented with progressive thoracic scoliosis who on evaluation was detected to have all the features of HGPPS syndrome. The patient underwent posterior correction of scoliosis uneventfully. A thorough literature search was performed to understand the descriptors of spinal deformity and its surgery in HGPPS syndrome. The spinal deformity in HGPPS resembles adolescent idiopathic scoliosis. Rapidly progressive right thoracic scoliosis was the usual pattern. Surgical and anesthetic considerations during surgery are similar to idiopathic scoliosis. These children tolerate surgery and anesthesia well. Neuromonitoring changes during surgery need to be interpreted correctly in the background of uncrossed sensory and motor tracts.

In several cancers, the efflux and resistance against doxorubicin (DOX), an effective anticancer drug, are associated with cellular iron deficiency and overexpression of the mitochondrial exporter ABCB8. Conversely, decreased ABCB8 expression and disrupted iron homeostasis in the heart have been implicated in DOX-associated cardiotoxicity. While studies have demonstrated that altered iron status can modulate the susceptibility to DOX cardiotoxicity, the exact molecular mechanisms have not been clearly understood. Here, we hypothesized that iron stores influence cardiac ABCB8 expression and consequently cardiac retention and toxicity of DOX. First, we found that ABCB8 deficiency in cardiomyocytes decreased DOX efflux, increased DOX-induced toxicity, and decreased cell viability. Conversely, intracellular DOX retention and toxicity were ameliorated by ABCB8 overexpression. To determine if altered cardiac iron status modifies ABCB8 expression, we treated cardiomyocytes with high iron or iron chelators. Western blot and qPCR analyses revealed that ABCB8 levels were decreased in iron overload and increased in iron deficiency. Subsequently, DOX retention and toxicity were increased in cardiomyocytes with iron overload, whereas iron deficiency ameliorated these effects. Next, we validated our results using a mouse model of hereditary hemochromatosis (HH), a genetic iron overload disorder. HH mice exhibited decreased ABCB8 expression and increased DOX retention and toxicity. These changes were abolished by the treatment of HH mice with a low-iron diet. Finally, cardiac-specific overexpression of ABCB8 in HH mice prevented cardiac DOX accumulation and abrogated DOX-induced cardiotoxicity without altering iron overload in the heart. Together, our results demonstrate that ABCB8 mediates DOX efflux and that iron regulates DOX retention and toxicity by altering cardiac ABCB8 expression. Our study identifies a novel role of iron in DOX-induced cardiotoxicity and suggests potential therapeutic intervention for DOX and anthracycline-based cancer pharmacology.

Classification systems for adolescent idiopathic scoliosis (AIS) have been in existence since the Schulthess system of 1905. Despite the numerous schema that have evolved over the last 115 years, little has changed from the original system based on the location of the coronal plane apex of the curves. Attempts at adding the sagittal plane, axial plane and shoulder balance to the system has generally yielded unscientific schemas or unwieldy numbers of variables within the scheme. The fundamental flaw with all these classifications is that they are based on two-dimensional imaging. The introduction of 3-D imaging like EOS and surface topography studies allow us an entirely novel perception of the spinal orientation in space. Thus the 3-D classifications that have emerged does not necessarily mean adding on Cartesian co-ordinates to the existing systems, but a far more comprehensive, yet simplistic view of the spinal deformity. Evidently, we are far from fully establishing all the variables and potentials of such schemas. Current modalities of 3-D imaging and evaluation are largely in the research domain and have not yet reached the clinical practice stage. The clinical utility of such 3-D classifications is also conjectural at present. But it is eminently possible that in the foreseeable future scoliosis classifications would cease to appear and be applied as they are today.

Introduction: Many Omani nationals travel to India for Spine surgery. Surgical site infection (SSI) rates in these patients is considered more than normal. The indications for surgery are also deemed liberal. Objective: To determine whether SSI rates are more in medical tourists. Materials & Methods: Design: The submission is a retrospective observational study done at a tertiary care referral hospital in Oman. The participants were a cohort of 125 patients who had travelled to India for spine surgery between January 2013 and December 2015. Their data was retrieved from the hospital information system. They were evaluated for satisfaction, residual complaints, surgical site infection and putative indications for surgery. The primary outcome measure was surgical site infection. The SSI rates were compared to a group of patients treated in-house during the same period. Results: All the surgeries done were in the private sector. Fifty-four of the 80 cases were advised surgery locally as well, while 26 were advised against intervention. There were 15 cases of SSI, 10 of them needing re-operation. Four patients had neurological deterioration with 2 wrong level surgeries. Discussion & Conclusions:: The rate of SSI in medical tourism patients was 12% compared to the 2.7% native cases. There was a 78% chance of improvement when the surgery was locally approved and 74% chance of worsening when not approved.

Background: Wide exposure to the anterior part of the upper cervical spine is difficult due to anatomical constraints. The Labio-Mandibulo-Glossotomy (LMG) approach is considered a difficult approach with high morbidity. The objective of this study is to describe the authors experience with the approach and it's outcomes in six cases and offer tips and pearls to the surgical access. Methods: This is a retrospective review of a small series of six cases that were operated for upper cervical lesions by the LMG approach. Two had mandible fractures that needed fixation and in the others osteotomy of the mandible was performed. The patients were followed up for minimum two years or death (in malignancy). We specifically looked for cosmetic or functional problems related to osteotomy, glossotomy, and, hospital and ICU stay duration. Surgical access is described in detail. Results: The hospital stay was similar to other major spine trauma or tumour surgeries at our center (median 14 days) and mean ICU stay 2.8 days. There were no long-term issues related to the access. Several tips and tricks are offered to minimize intra and post-operative problems. Conclusions: The LMG approach, though apparently formidable, is quite a safe and simple procedure with few residual complications.

Aim: This study is aimed to assess the effect of different mouth rinses and its active components on the force decay of elastomeric chains. Listerine, Colgate Phos-Flur, Clohex Plus mouth rinses, 26.9% alcohol, 0.04% sodium fluoride (NaF), and 0.2% chlorhexidine were used for this study to determine its effects on force decay of elastomeric chains. Materials and Methods: Seven custom-made jigs were constructed on which 120 short module elastomeric chains were stretched to predetermined lengths between the pins. Using calibrated digital force tester, measurements of force exerted by the elastomeric chains while stretched on the framework were recorded at the time of attachment to the frame and after 24 hours, 7 days, 14 days, 21 days, and 28 days. The custom-made jigs and the elastomeric chains were allowed for complete submersion in artificial saliva throughout the test period, as well as in respective control solution and mouth rinses for 60 seconds, twice daily. Results: All test groups showed significantly more force decay than the control group. Statistically significant differences were observed when comparing force decay among the test groups except between a few. Interpretation and Conclusion: Mouth rinses cause an increase in force decay of elastomeric chain over the time. Listerine and 26.9% alcohol solution caused maximum force decay by the end of 28 days. Least force degradation of elastomeric chain was seen with the use of 0.2% chlorhexidine.

Persistence of resistant leukemic cells after therapy is the main cause of relapse. Here, the authors show that mesenchymal stem cells-derived PML is involved in the maintenance of leukemia cells through Cxcl1 and IL6 and that PML inhibition enhances sensitivity to chemotherapy.

Aim: Several plan quality metrics are available for the evaluation of stereotactic radiosurgery/radiotherapy plans. This is a retrospective analysis of 60 clinical treatment plans of arteriovenous malformation (AVM) patients to study clinical usefulness of selected plan quality metrics. Materials and Methods: The treatment coverage parameters Radiation Therapy Oncology Group (RTOG) Conformity Index (CIRTOG), RTOG Quality of Coverage (QRTOG), RTOG Homogeneity Index (HIRTOG), Lomax Conformity Index (CILomax), Paddick's Conformity Index (CIPaddick), and dose gradient parameters Paddick's Gradient Index (GIPaddick) and Equivalent Fall-off Distance (EFOD) were calculated for the cohort of patients. Before analyzing patient plans, the influence of calculation grid size on selected plan quality metrics was studied on spherical targets. Results: It was found that the plan quality metrics are independent of calculation grid size ≤2 mm. EFOD was found to increase linearly with increase in target volume, and a linear fit equation was obtained. Conclusions: The analysis shows that RTOG indices and EFOD would suffice for routine clinical radiosurgical treatment plan evaluation if a dose distribution is available for visual inspection.

Atherosclerosis, a chronic inflammatory disorder characterized by endothelial dysfunction and blood vessel narrowing, is the leading cause of cardiovascular diseases including heart attack and stroke. Herein, we present a novel tunable microfluidic atherosclerosis model to study vascular inflammation and leukocyte-endothelial interactions in 3D vessel stenosis. Flow and shear stress profiles were characterized in pneumatic-controlled stenosis conditions (0%, 50% and 80% constriction) using fluid simulation and experimental beads perfusion. Due to non-uniform fluid flow at the 3D stenosis, distinct monocyte (THP-1) adhesion patterns on inflamed [tumor necrosis factor-α (TNF-α) treated] endothelium were observed, and there was a differential endothelial expression of intercellular adhesion molecule-1 (ICAM-1) at the constriction region. Whole blood perfusion studies also showed increased leukocyte interactions (cell rolling and adherence) at the stenosis of healthy and inflamed endothelium, clearly highlighting the importance of vascular inflammation, flow disturbance, and vessel geometry in recapitulating atherogenic microenvironment. To demonstrate inflammatory risk assessment using leukocytes as functional biomarkers, we perfused whole blood samples into the developed microdevices (80% constriction) and observed significant dose-dependent effects of leukocyte adhesion in healthy and inflamed (TNF-α treated) blood samples. Taken together, the 3D stenosis chip facilitates quantitative study of hemodynamics and leukocyte-endothelial interactions, and can be further developed into a point-of-care blood profiling device for atherosclerosis and other vascular diseases.

BackgroundObstructive sleep apnea (OSA) is an independent risk factor for many cardiovascular conditions such as coronary artery disease, myocardial infarction, systemic hypertension, pulmonary hypertension, and stroke. However, the association of OSA with outcomes in patients hospitalized for ST‐elevation myocardial infarction remains controversial. Methods and ResultsWe used the nation‐wide inpatient sample between 2003 and 2011 to identify patients with a primary discharge diagnosis of ST‐elevation myocardial infarction and then used the International Classification of Diseases, Clinical Modification code 327.23 to identify a group of patients with OSA. The primary outcome of interest was in‐hospital mortality, and secondary outcomes were in‐hospital cardiac arrest, length of stay and hospital charges. Our cohort included 1 850 625 patients with ST‐elevation myocardial infarction, of which 1.3% (24 623) had documented OSA. OSA patients were younger and more likely to be male, smokers, and have chronic pulmonary disease, depression, hypertension, known history of coronary artery disease, dyslipidemia, obesity, and renal failure (P