Use of dual-mobility cup in primary total hip arthroplasties: an Italian regional register (RIPO) study on three thousand, seven hundred and ten cases.

PURPOSE: The purpose of the study was to investigate the outcome of dual-mobility cup (DM) compared with a standard cup (SC) in primary total hip arthroplasty (THA) in the long-term follow-up based on a regional Italian joint registry (RIPO). METHODS: The Registry of Prosthetic Orthopaedic Implant (RIPO) was consulted, looking for all primary THAs implanted from 2000 to 2019. Three thousand seven hundred ten were dual-mobility cup (DM) total hip arthroplasties (THA) and 85.816 were standard cup (SC) THAs, on a total of 89.526 primary THA. Demographics, survival rates and causes of revision were evaluated and compared between the two groups. RESULTS: The use of DM progressively increased from 0.4% in 2000 to 7.5% in 2018 of all primary THAs. Revision rate was 3.5% (128 on 3710) for DMC and 4.7% (4061 on 85,816) for SC. DM presented lower dislocation rate if compared to SC with 22-28-mm femoral head diameter. However, DM showed a higher risk of revision for any causes than SC with 32-mm femoral head diameter in long-term follow-up. Nevertheless, no significant difference was measured in terms of demographics and surgical approach for dislocation rate. CONCLUSIONS: The DM cup represents a valid implant solution and has a lower dislocation rate than 22-28-mm SC. A slight increase in the use of DM implants over time was observed in the RIPO. However, a larger population and a longer follow-up are needed to further monitor the survival rate of new-generation DM implants.

Hip stability parameters with dual mobility, modular dual mobility and fixed bearing in total hip arthroplasty: an analytical evaluation.

BACKGROUND: Use of dual mobility (DM) in total hip arthroplasty has gained popularity due to the ability to reduce dislocation through increased jumping distance and impingement-free arc of movement. Recently, modular dual mobility (modDM) systems were introduced to give the possibility to use DM with standard metal-backed shells, however few has been studied to date regarding how jumping distance and the center of rotation change with modDM. The objective of this study was to evaluate, through analytical simulation, how jumping distance, center of rotation and arc of movement change between DM and standard cups with modDM or fixed bearings (FB). METHODS: 3D-models of DM and standard press-fit cups with modDM or FB liners were used to simulate DM, modDM and FB implant configurations, matched for same cup size, according to same cup position and different femoral head diameters. Jumping distance was calculated and center of rotation lateralization and oscillation angles were measured for each size of these three implant configurations. RESULTS: Jumping distance with modDM was reduced by -3.9 mm to -8.6 mm in comparison with DM, from 48 to 64 mm size, but resulted comparable to polyethylene 36 mm FB and increased by + 1.1 mm and + 1.4 mm than ceramic 36 and 40 mm FBs for sizes > 54 mm. ModDM lateralized the center of rotation up to + 2.5 mm and + 4.0 mm in comparison with DM and FBs, respectively. Oscillation angle with modDM resulted higher than + 16°, + 23°, + 17° and + 14° in comparison to DM, 28 mm, 32 mm and 36 mm FB cups, respectively, for 56 mm cup size. CONCLUSIONS: According to its specific design, modDM might change hip stability parameters in comparison to DM, worsening jumping distance and center of rotation position, but increasing arc of movement. As not restoring stability parameters in the same fashion, modDM implants should be properly used when DM cups are not feasible.

A rapid screening method for testing the efficiency of masks in breaking down aerosols.

The highest risk of novel coronavirus SARS-CoV-2 to be spread through human-to-human transmission has boosted the use of personal protective equipment at worldwide level. In Europe, the medical face masks must be tested to certify the essential requirements in agreement with European Standard EN 14683:2019, and face masks for industrial use in agreement with European Standard EN 149:2009. Due to the need of large quantitative of medical and non-medical face masks in coronavirus outbreak, several Italian industries are working for shift a portion of their manufacturing capacity for producing medical and non-medical face mask. For screening evaluation of the effectiveness of personal protective equipment produced by reconverted industries, ARPA Lazio and the Department of Chemical Science and Technologies of Tor Vergata University have set-up an analytical system able to simulate the respiratory action and to measure the percentage of particles that pass through the face masks using optical particle counter (based on the EN 16890: 2017 that uses the same light scattering principle to evaluate the filter filtration efficiency). This set-up was challenged using face masks produced by reconverted industries and the data were compared with ones obtained using medical face mask.

Fate of Large-Scale Structure in Modified Gravity After GW170817 and GRB170817A.

The coincident detection of gravitational waves (GW) and a gamma-ray burst from a merger of neutron stars has placed an extremely stringent bound on the speed of GWs. We showed previously that the presence of gravitational slip (η) in cosmology is intimately tied to modifications of GW propagation. This new constraint implies that the only remaining viable source of gravitational slip is a conformal coupling to gravity in scalar-tensor theories, while viable vector-tensor theories cannot now generate gravitational slip at all. We discuss structure formation in the remaining viable models, demonstrating that (i) the dark-matter growth rate must now be at least as fast as in general relativity (GR), with the possible exception of that beyond the Horndeski model, and (ii) if there is any scale dependence at all in the slip parameter, it is such that it takes the GR value at large scales. We show a consistency relation that must be violated if gravity is modified.

Cosmology and fundamental physics with the Euclid satellite.

Euclid is a European Space Agency medium-class mission selected for launch in 2020 within the cosmic vision 2015-2025 program. The main goal of Euclid is to understand the origin of the accelerated expansion of the universe. Euclid will explore the expansion history of the universe and the evolution of cosmic structures by measuring shapes and red-shifts of galaxies as well as the distribution of clusters of galaxies over a large fraction of the sky. Although the main driver for Euclid is the nature of dark energy, Euclid science covers a vast range of topics, from cosmology to galaxy evolution to planetary research. In this review we focus on cosmology and fundamental physics, with a strong emphasis on science beyond the current standard models. We discuss five broad topics: dark energy and modified gravity, dark matter, initial conditions, basic assumptions and questions of methodology in the data analysis. This review has been planned and carried out within Euclid's Theory Working Group and is meant to provide a guide to the scientific themes that will underlie the activity of the group during the preparation of the Euclid mission.

Anisotropic stress as a signature of nonstandard propagation of gravitational waves.

We make precise the heretofore ambiguous statement that anisotropic stress is a sign of a modification of gravity. We show that in cosmological solutions of very general classes of models extending gravity-all scalar-tensor theories (Horndeski), Einstein-aether models, and bimetric massive gravity-a direct correspondence exists between perfect fluids apparently carrying anisotropic stress and a modification in the propagation of gravitational waves. Since the anisotropic stress can be measured in a model-independent manner, a comparison of the behavior of gravitational waves from cosmological sources with large-scale-structure formation could, in principle, lead to new constraints on the theory of gravity.

Sitting imbalance cause and consequence of post-traumatic Charcot spine in paraplegic patients.

PURPOSE: To analyze the role of spine alignment in post-traumatic paraplegic patient as a potential cause of late Charcot spine disease (CSD). METHOD: A retrospective review of three cases in which the disease appeared more than 15 years after a spinal cord injury treated by posterior fusion. A review of the literature concerning spine balance in sitting position, especially referred to paraplegic patients, is done to validate this hypothesis. RESULTS: Lumbar kyphosis in paraplegic patients during the sitting position may increase the mechanical load on disks and ligament below the previously fused area. This phenomenon, in combination with lack of protective mechanism because of poor muscular support and lack of sensitivity can speed up and amplify the normal degenerative changes in the disk and ligaments. CONCLUSIONS: More investigations are required to fully understand all the mechanisms underlying CSD pathogenesis to prevent it. Until then, a systematic long-term clinical and radiological follow-up in all post-trauma paraplegic patients is suggested. Combined anterior and posterior fusion, when feasible, can restore the sagittal balance providing a better quality of life in these patients.

Summary recommendations on "Analytical methods for substances in the Watch List under the Water Framework Directive".

The Watch List (WL) is a monitoring program under the European Water Framework Directive (WFD) to obtain high-quality Union-wide monitoring data on potential water pollutants for which scarce monitoring data or data of insufficient quality are available. The main purpose of the WL data collection is to determine if the substances pose a risk to the aquatic environment at EU level and subsequently to decide whether a threshold, the Environmental Quality Standards (EQS) should be set for them and, potentially to be listed as priority substance in the WFD. The first WL was established in 2015 and contained 10 individual or groups of substances while the 4th WL was launched in 2022. The results of monitoring the substances of the first WL showed that some countries had difficulties to reach an analytical Limit of Quantification (LOQ) below or equal to the Predicted No-Effect Concentrations (PNEC) or EQS. The Joint Research Centre (JRC) of the European Commission (EC) organised a series of workshops to support the EU Member States (MS) and their activities under the WFD. Sharing the knowledge among the Member States on the analytical methods is important to deliver good data quality. The outcome and the discussion engaged with the experts are described in this paper, and in addition a literature review of the most important publications on the analysis of 17-alpha-ethinylestradiol (EE2), amoxicillin, ciprofloxacin, metaflumizone, fipronil, metformin, and guanylurea from the last years is presented.

Cosmic variance and the measurement of the local Hubble parameter.

There is an approximately 9% discrepancy, corresponding to 2.4 σ, between two independent constraints on the expansion rate of the Universe: one indirectly arising from the cosmic microwave background and baryon acoustic oscillations and one more directly obtained from local measurements of the relation between redshifts and distances to sources. We argue that by taking into account the local gravitational potential at the position of the observer this tension--strengthened by the recent Planck results--is partially relieved and the concordance of the Standard Model of cosmology increased. We estimate that measurements of the local Hubble constant are subject to a cosmic variance of about 2.4% (limiting the local sample to redshifts z > 0.010) or 1.3% (limiting it to z > 0.023), a more significant correction than that taken into account already. Nonetheless, we show that one would need a very rare fluctuation to fully explain the offset in the Hubble rates. If this tension is further strengthened, a cosmology beyond the Standard Model may prove necessary.

Endoscopic excision of C2 Osteoid Osteoma: a technical case report.

PURPOSE: The Authors illustrate the feasibility of an open biopsy and complete excision of Osteoid Osteoma involving the C2 vertebral body performed via endoscopic anterior cervical approach. METHODS: A 23-year-old male patient with history of delayed diagnosis of cervical Osteoid Osteoma underwent evaluation and surgical treatment: the minimally invasive procedure and techniques were described. The clinical features, the radiological findings and the outcome were assessed. Complications and local recurrences were also recorded. RESULTS: There were no intra- or post-operative complications. Immediately after surgery the typical Osteoid Osteoma related pain disappeared. At three years follow-up the patient was asymptomatic and considered disease-free: CT-scan and x-Ray showed no local recurrence and C2-C3 interbody fusion with cervical plate in site. CONCLUSIONS: The endoscopic transcervical surgery represents an interesting option for the treatment of these diseases in difficult areas of the upper cervical spine, also minimizing soft tissue trauma and collateral damage allows patients a faster and complete return to normal function. To our knowledge this is the first report of cervical spine tumor removal using this minimally invasive approach.

Occipito-cervical fusion in post-traumatic instability of the upper cervical spine and cranio-cervical junction.

INTRODUCTION: Surgical management of upper cervical spine (UCS) unstable injuries may be challenging as the number of cases requiring this surgery collected in every single center is small. This retrospective study was conducted to analyze the radiographic and clinical results in 12 patients undergoing a posterior occipito-cervical fusion by a polyaxial screws-rod-plate system. METHODS: There were eight male and four female patients with a mean age of 73.7 years (range 32-89 years). Six patients presented neurologic deficits at admission. Six patients had sustained major trauma. The remaining six patients had suffered a minor trauma. RESULTS: Two patients died postoperatively in Intensive Care Unit. All surviving patients achieved solid fusion at 6 months. No surviving patient had neurological deterioration postoperatively. There were no instrumentation failures or revision required. Two patients suffered from superficial occipital wound infection. CONCLUSIONS: Although the indication to occipito-cervical fusion decreased since the new C1-C2 posterior fixation techniques were described, it remains a valid and reliable option in UCS post-traumatic instability to be applied even in emergency especially in the elderly.

Complications in minimally invasive percutaneous fixation of thoracic and lumbar spine fractures and tumors.

PURPOSE: We propose to evaluate the complication rate in minimally invasive stabilization (MIS) for spine fractures and tumors, as a common alternative to open fusion and conservative treatment. METHODS: From 2000 to 2010, 187 patients were treated by minimally invasive percutaneous fixation in 133 traumatic fractures and 54 primitive and/or secondary spine tumors. Complications were classified, according to the period of onset as intraoperative and postoperative, and according to the severity, as major and minor. RESULTS: A total of 15 complications (8 %) were recorded: 5 intraoperative (3 %), 6 early postoperative (3 %) and 4 late postoperative (2 %); 6 were minor complications (3 %) and 9 were major complications (5 %). CONCLUSIONS: Minimally invasive stabilization of selected spine pathologies appears to be a safe technique with low complication rate and high patient satisfaction. MIS reduces hospitalization and allows a fast functional recovery improving the quality of life.

Cosmology and Fundamental Physics with the Euclid Satellite.

Euclid is a European Space Agency medium-class mission selected for launch in 2019 within the Cosmic Vision 2015-2025 program. The main goal of Euclid is to understand the origin of the accelerated expansion of the universe. Euclid will explore the expansion history of the universe and the evolution of cosmic structures by measuring shapes and red-shifts of galaxies as well as the distribution of clusters of galaxies over a large fraction of the sky. Although the main driver for Euclid is the nature of dark energy, Euclid science covers a vast range of topics, from cosmology to galaxy evolution to planetary research. In this review we focus on cosmology and fundamental physics, with a strong emphasis on science beyond the current standard models. We discuss five broad topics: dark energy and modified gravity, dark matter, initial conditions, basic assumptions and questions of methodology in the data analysis. This review has been planned and carried out within Euclid's Theory Working Group and is meant to provide a guide to the scientific themes that will underlie the activity of the group during the preparation of the Euclid mission.

Modular dual mobility articulation in primary and revision hip arthroplasty: lights and shadows.

PURPOSE: The use of dual mobility cups in total hip arthroplasty has gained popularity in light of the fact it enables to reduce dislocation through increased jumping distance (JD) and impingement-free arc of movement. Modular Dual Mobility Cup (modular DMC) systems have been recently introduced to enable the use of dual mobility cups with standard metal-backed shells. The objective of this study was twofold: calculate the JD for each modular DMC system and conduct a systematic literature review to report clinical outcomes and reasons for failure of this construct. METHODS: The JD was calculated using the Sariali formula: JD = 2Rsin [(π/2 - Ψ - arcsin (offset/R))/2]. A qualitative systematic literature review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive search for English and French articles between January 2000 and July 2020 was run on PubMed, EMBASE, Google Scholar, and Scopus with the primary objective of finding articles about modular DMC systems. RESULTS: We identified eight 8 different manufacturers of modular DMC systems and 327 publications on the subject. After screening for duplicates and eligibility, we identified 229 publications: 206 articles were excluded because they contained no reports on modular DMC systems, whereas other three were not included because they focused on biomechanical aspects. Among the 11 included articles, 2 were prospective case series, 9 were retrospective case series. True dislocation occurred in 25 cases (0.9%), and six of them were solved by closed reduction without necessity of revision, while all 5 intraprosthetic dislocations were operated. CONCLUSIONS: Modular DMCs are a valid method to deal with complex THA instability, with good clinical and patient-reported outcomes, low complication rates, and low revision rates at early follow-up. We would advise cautious optimism on the role of modular DMC implants, as it seems safer to use ceramic instead of metallic heads whenever possible to avoid the increase cobalt and chromium trace ion serum levels.

Solitary eosinophilic granuloma of the adult lumbar spine.

INTRODUCTION: Eosinophilic granuloma (EG) is a benign bone tumor that rarely occurs in adults. It is usually found occurring in flat and long bones, but spine is often affected too. EG is of unknown aetiology, and the course of the disease is unpredictable. MATERIALS AND METHODS: Two cases of EG of the adult lumbar spine are reported, representing a difficult challenge for diagnosis and treatment. CONCLUSION: CT scan guided trocar biopsy allowed to achieve a definitive diagnosis, and CT scan guided intralesional infiltrations of corticosteroids were the successful treatment.

Influence of a thread wire saw guide and spinal cord protector device in "en bloc" vertebrectomies.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The objective of the study was to describe and compare the surgical outcomes between the use of a new auto static spinal cord and thread wire guiding device and the traditional scalpel technique for en bloc vertebrectomies using only the posterior approach. SUMMARY OF BACKGROUND DATA: As en bloc vertebrectomy has become more accepted as the ideal treatment for selected cases of spine tumors, its high morbidity has to be kept in mind. Uneven cutting surfaces and high risk of spinal cord lesions are among the problems. Although some modifications of the technique and development of new devices to minimize the risks have been reported, there are still some pitfalls associated with them. METHODS: Twenty-five patients, divided into 2 groups, were retrospectively reviewed. Patients in group 1 (G1) were operated using the device, and the patients in group 2 (G2) underwent en bloc vertebrectomy by the traditional scalpel technique. The surgical time, amount of blood loss based on the total volume of blood transfusion during surgery, and the rate of complication were compared. RESULTS: No differences regarding sex, age, and preoperative status occurred. The mean operative time was 294 and 388 minutes and the mean volume of transfused blood was 37 and 53 mL/kg for G1 and G2, respectively. These differences were not statistically significant. CONCLUSIONS: Patient selection and surgical experience are the best outcome predictors. However, methods to reduce the risks of neural lesions, surgical time, and blood loss should always be applied, specially dealing with highly morbid and demanding procedures in the spine.

Vertebroplasty: benefits are more than risks in selected and evidence-based informed patients. A retrospective study of 59 cases.

Vertebral compression fractures represent a frequent pathology among elderly population, with potentially devastating consequences. More than 20 years have passed since percutaneous vertebroplasty was initially used in the treatment of angiomas, representing nowadays a widely used treatment for osteoporotic vertebral fractures. The authors present a retrospective review of 59 consecutive patients (in total 94 fractured levels) that underwent polymethylmethacrylate percutaneous vertebroplasty for vertebral compression fractures due to senile or secondary osteoporosis. All fractures were free from neurologic involvement and were classified as A1 type according to Magerl classification. All of patients were initially treated conservatively, by application of orthosis that allows immediate deambulation. At control, patients who complained of pain and limitation of daily activities underwent MRI. If presence of marrow signal changes, especially hypertense signal in T2-weighted images was confirmed, percutaneous vertebroplasty procedure was performed (we could call it "sub-acute" procedure). A limited group of patients that did not tolerate brace and had an insufficient pain control underwent vertebroplasty "in acute", few days after fracture. Immediate post-operative pain reduction and follow-up clinical outcome (estimating quality of life and residual back pain) were evaluated by means of Visual Analogue Scale, SF-36 and Oswestry Disability Index. In the immediate post-operative course a significant pain relief was found in 39 patients (66.1%), moderate pain relief in 17 (28.8%), while 3 (5.1%) did not achieve relevant pain improvement. Pain intensity and life quality was maintained within satisfactory limits after a mean follow-up of 16 months. In conclusion, percutaneous vertebroplasty is an effective and safe procedure for treating vertebral compression fractures in the elderly. It provides immediate pain relief and allows early mobilization, thus avoiding potentially severe complications related to persistent back pain and prolonged bed rest. When performed by experienced surgeon complication rate is low, representing a safe procedure, able to provide a satisfactory outcome.

Fenestrated pedicle screws for cement-augmented purchase in patients with bone softening: a review of 21 cases.

BACKGROUND: This prospective mixed cohort study was designed to evaluate the middle- to long-term purchase of cement-augmented pedicular screws in patients with poor bone quality. The growing number of surgical procedures performed in the spine has highlighted the problem of screws loosening in patients with poor bone stock due to osteoporosis and/or tumors. Different methods of increasing screw purchase have been reported in the literature, including polymethylmethacrylate (PMMA) augmentation. MATERIALS AND METHODS: From September 2006 to April 2008, 21 patients with a poor bone stock condition due to osteoporosis or tumor underwent posterior stabilization by fenestrated pedicle screws and PMMA augmentation. Pain improvement and long-term clinical outcome were assessed by visual analogue scale (VAS) score and SF-36 health survey (SF-36) questionnaire. Implant stability was evaluated by plain radiography and CT scans performed three days after surgery and every three months thereafter. After the first 12 months, radiologic controls were taken once a year in all surviving patients. Complications were evaluated in all cases. RESULTS: All patients were clinically and radiographically followed up for a mean of 36 months. VAS scores and SF-36 questionnaires showed a statistically significant reduction in pain and improvement in the quality of life. No radiological loosening or pulling out of screws was observed. In two cases, cement leakage occurred intraoperatively: one patient who suffered from a transitory nerve root palsy improved spontaneously, while the surgeon immediately removed the excess cement before setting in the other case. In three cases, the post-op CT scan revealed a small amount of cement in the canal without clinical relevance. CONCLUSIONS: Fenestrated screws for cement augmentation provided effective and lasting purchase in patients with poor bone quality due to osteoporosis or tumors. No case of loosening was recorded after a mean follow-up of 36 months. The only clinical complication strictly related to PMMA screw augmentation did not require further surgery.

Posterior Osteotomy and Osteosynthesis for Malunited Atlas Fracture: A Surgical Technique.

Conservative treatment is commonly accepted and widely used for most atlas compression fractures. Malunion due to mismatching of the articular surfaces in C0-C1 and C1-C2 is therefore frequent even without associated instability. Such a result is considered acceptable in the elderly with low functional requests but should be avoided in young patients. Authors describe a new surgical technique to reduce and fix a nonunion and malunited fracture of the atlas through a posterior arch osteotomy followed by articular masses stabilization with polyaxial screws and precurved titanium rod. Rod prebending reduces lateral inclination of the screw heads during the reduction maneuver through compression applied between screw heads making it effective.