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Clinical and laboratory factors influencing the discontinuation of second-line antirheumatic drugs were prospectively studied using survival analysis in a consecutive series of 245 patients with recently diagnosed rheumatoid arthritis. A statistically significant influence of age, sex, serum IgA and HLA-DR3 on the discontinuation rate of chrysotherapy because of toxicity was observed. The discontinuation of sulfasalazine was increased by advanced age and high rank order of prescription. With respect to efficacy, high initial disease activity appeared to predispose to treatment termination of hydroxychloroquine, sulfasalazine and penicillamine. Furthermore, an influence of the rank order of prescription on discontinuation of sulfasalazine therapy because of lack of efficacy was found. Of interest is that discontinuation of hydroxychloroquine therapy because of lack of efficacy occurred less frequently in HLA-DR3-positive than in HLA-DR3-negative patients. Although these prognostic factors are of secondary importance in clinical practice, they may be of significance in the interpretation and comparison of clinical trials.

Background Although many studies focus on short-term side effects of radioiodine therapy, almost none studied long-term side effects. We assessed radioiodine long-term salivary side effects after radioiodine treatment for differentiated papillary thyroid carcinoma and compared it to short-term morbidity within the same population. Methods A standardized self-administrated questionnaire was submitted in 2019 by patients treated with radioiodine between January 2011 and December 2012. These patients had already answered the same questionnaire 6 years before. Results Our study showed a significant reduction for salivary side effects: discomfort in submandibular or parotid area, swelling, pain, a bad or salty taste in the mouth, allowing to get back to a "normal" diet. Conclusions Our study suggests that a significant rate of patients will recover from I131 therapy salivary side effects. As almost 30% of these remissions happened during our late stage follow-up, we highlight the necessity of a long-term follow-up in these patients.

International audience; Purpose: Patient data management systems (PDMS) are widely used in intensive care units (ICUs) to improve care traceability. Verbal orders are still used for prescriptions requiring immediate execution but should be subsequently recorded in the system. We assessed the rapid sequence induction (RSI) traceability for endotracheal intubation in an ICU dedicated PDMS.Materials and methods: A retrospective study was conducted on anonymous databases in 21 ICUs. Endotracheal tube insertions performed during one year were compared to the number of RSI registered in the PDMS.Results: We listed 5516 endotracheal tube insertions. A suxamethonium injection was registered in 829 cases and a rocuronium administration in 909 cases. The RSI traceability rate in the overall cohort was 31.5% and was greater in the units where nurses were allowed to record a drug administration before the computerized physician order entry.Conclusions: PDMS are supposed to improve prescription completeness and traceability, but our study suggests an opposite result. A co-responsibility policy between physicians and nurses should be promoted to improve care traceability. PDMS ergonomic improvements and enhanced integration in clinical workflow might also result in better compliance with documentation requirements. In each centre, indicators of PDMS correct use should be defined and periodically monitored.

We conducted a pilot study of a potential endoscopic alternative to bariatric surgery. We developed a Natural Orifice Transluminal Endoscopic Surgery (NOTES) gastric bypass with controlled bypass limb length using four new devices including a dedicated lumen-apposing metal stent (GJ-LAMS) and pyloric duodenal exclusion device (DED). We evaluated procedural technical success, weight change from baseline, and adverse events in growing Landrace/Large-White pigs through 38 weeks after GJ-LAMS placement. Six pigs (age 2.5 months, mean baseline weight 26.1 ± 2.7 kg) had initial GJ-LAMS placement with controlled bypass limb length, followed by DED placement at 2 weeks. Technical success was 100%. GJ-LAMS migrated in 3 of 6, and DED migrated in 3 of 5 surviving pigs after mucosal abrasion. One pig died by Day 94. At 38 weeks, necropsy showed 100–240 cm limb length except for one at 760 cm. Weight gain was significantly lower in the pigs that underwent endoscopic bypass procedures compared to expected weight for age. This first survival study of a fully endoscopic controlled bypass length gastrojejunostomy with duodenal exclusion in a growing porcine model showed high technical success but significant adverse events. Future studies will include procedural and device optimizations and comparison to a control group.

OBJECTIVES The objective of this in vitro study was to compare Doppler versus catheter transvalvular pressure gradients (TPG) in third generations balloon-expandable (BE) versus self-expanding (SE) transcatheter heart valves (THV). BACKGROUND TPG is a key parameter to assess and follow valve hemodynamic function following transcatheter aortic valve implantation (TAVI). It remains uncertain and debated whether, and to which extent, TPGs differ according to the type of THV, that is, BE versus SE and to the method used for TPG measurement, that is, Doppler echocardiography versus cardiac catheterization. METHODS The CoreValve EVOLUT PRO 26 mm and the SAPIEN 3 23 mm THVs were tested in a left heart simulator using a 21 mm aortic annulus under following conditions: heart rate: 70 bpm, mean aortic pressure: 100 mmHg, stroke volume: 30, 70 and 100 ml. Mean TPGs were measured by continuous-wave Doppler and by micro-tip pressure catheters positioned in the left ventricle and at 50 mm downstream to the tip of the THV leaflets. RESULTS Doppler TPGs (9.5 ± 3.9 mmHg) were on average 40.5 ± 13.9% higher (p

Influence of footwear on posture in athletes is poorly documented despite its potential impact on biomechanics and injury risk. The aim of this study was to investigate effects of different footwear geometries on comfort and posture on a cohort of 48 elite rugby players. Spine posture was characterized by photogrammetry, while center of pressure was measured by means of a force platform. Three different footwear outsoles architectures (one rugby shoe with flat outsole, one rugby shoe with a 10 mm heel rise and foot arch support, and a running shoe with a 10mm heel rise and foot arch support) were compared to non-shod in randomized order. Then comfort felt at the level of foot and spine was also estimated by subjective questionnaires. Compared to the flat rugby model, both other models induced significantly (p

International audience; The coronavirus disease 2019 (COVID-19) outbreak has had a major impact on medical and surgical activities. A decline in facial trauma incidence was noticed during the lockdown period. The aim of this study was to evaluate the decline in maxillofacial trauma in France during this particular period. A retrospective multicentre comparative study was initiated in 13 major French public hospital centres. The incidence of facial trauma requiring surgery during the first month of lockdown was compared to that during equivalent periods in 2018 and 2019. Differences in the types of trauma were also analysed. Thirteen maxillofacial departments participated in the study. A significant decline in maxillofacial trauma volumes was observed when compared to equivalent periods in 2018 and 2019 (106 patients compared to 318 and 296 patients, respectively), with an average reduction of 65.5% (P = 0.00087). The proportion of trauma due to sports and leisure was reduced when compared to reports in the literature. As a consequence, in the context of a pandemic, the material and human resources related to this activity could be reallocated to the management of other pathologies that cannot be postponed.

Objective: This study aimed to analyze the morphology of the hypoplasic mandible and its evolution during the growth period to better understand how it differs from the pediatric healthy mandible. Method: Three-dimensional mandibular models of hypoplasic and healthy children aged from 39 gestational weeks to 7 years old were analyzed with a morphometric method including data clustering. Morphological distinctions between pathological and healthy mandibles were highlighted. Bilateral and unilateral mandibular hypoplasia were distinguished. Results: The study sample was composed of 31 hypoplasic children and as many sex- and age-matched healthy children. Morphological distinctions between pathological and healthy mandibles were highlighted only from the first year of life. In bilateral hypoplasia, the overall mandibular dimensions were reduced while there was only a ramus asymmetry in unilateral mandibular hypoplasia (mean ± SD of the difference between the Grp03c and Grp03b subgroups: 6.80 ± 6.37 – P value = 1.64e–3 for the height of the left ramus versus 0.18 ± 4.18 – P value = .82 for the height of the right ramus). Supervised classification trees were built to identify the pathology and discriminate unilateral from bilateral mandibular hypoplasia (prediction rates = 81% and 84%, respectively). Conclusions: Based on a morphometric analysis, we demonstrated that mandibular hypoplasia significantly impacts the mandibular morphology only from the first year of life, with a distinction between bilateral and unilateral hypoplasia.

Objective: Proprioceptive senses play an important role in human body reflex and movement, so far implementing physiological mathematical models of proprioceptors in the musculoskeletal model and investigating their effects have not been sufficiently investigated. The purpose of the present study was to establish a compact framework for a lower limb musculoskeletal model by considering both ascending signals from central nervous system and descending feedback neural signal from physiologically realistic proprioceptors and evaluate it with progressive experimental data as well as investigating the effects of the proprioceptive feedback on the human movement. Methods: The simulation framework was established by combining a lower limb musculoskeletal model, the forward dynamic tool from OpenSim codes, and an executive program based on Python codes. The physiological mathematical models of the muscle spindle and Golgi tendon organs were included in the feedback control loop for the model. The model was evaluated through both previous literature data and currently implemented volunteer reflex experiments from the neural organ level to the monosynaptic reflex loop, and finally the complicated movement, such as the firing rate of the proprioceptors, the knee-jerk reflex, and the normal gait. Simultaneously, the effects of the proprioceptors on human normal gait were initially investigated. Results: The reliability of the framework was properly evaluated by comparing the experimental data of neural firing rate, electromyography signals, and joint kinematics. The gait analysis indicated that the introduction of the proprioceptors in the motor control loop can substantially resist the external disturbance. Conclusion: The established framework has been evaluated at different levels, and it can be extended and applied to different musculoskeletal models for human movement analysis and evaluate the effects of the proprioceptors on them.

The development of artificial prosthetic lower limbs aims to improve patient’s mobility while avoiding secondary problems resulting from the use of the prostheses themselves. The residual limb is a pressure-sensitive area where skin injuries and pain are more likely to develop. Requirements for adequate prosthetic limbs have now become urgent to improve amputee’s quality of life. This study aims to understand how socket design parameters related to geometry can influence pressure distribution in the residual limb. A finite element model was developed to simulate the mechanical loading applied on the residual limb of a below-knee amputee while walking. A sensitivity analysis to socket initial geometry, scaling the socket downward in the horizontal plane, was performed. Recordings include stress levels on the skin and in the residual limb deep soft tissues. Peak stress was reduced by up to 51% with a limited reduction of the socket size. More important scale reduction of the residual limb would lead to possible negative effects, such as stress concentrations in sensitive areas. This result confirms the interest of the prosthetist to develop a well-fitting socket, possibly a little smaller than the residual limb itself, in order to avoid residual limb mobility in the socket that could cause friction and stress concentrations. Non-homogeneous geometrical reductions of the socket should be further investigated.

An ectopic accessory parotid gland with a congenital cheek fistula is a rare congenital condition that belongs to the oculoauriculovertebral spectrum. The clinical symptom is generally a cheek fistula. Surgical treatment can include either the removal of the ectopic gland or a duct transposition. We describe a sialendoscopy-assisted duct transposition and its associated surgical management. Sialendoscopy helped identify the fistula tract through the mucosa. Sialendoscopy-assisted duct transposition in treating an ectopic accessory parotid gland proved to be a safe and minimally invasive procedure. The required incisions were small, which makes this type of surgery more straightforward and more precise.

Calcified aortic stenoses are among the most prevalent form of cardiovascular diseases in the industrialized countries. This progressive disease, with no effective medical therapy, ultimately requi...

International audience; The wealth of data in the National Cancer Database (NCDB) has allowed numerous studies investigating patient, disease, and treatment-related factors in oral cavity squamous cell carcinoma (OCSCC); however, to date, no summation of these studies has been performed. The aim of this study was to provide a concise review of the NCDB studies on OCSCC, with the hopes of providing a framework for future, novel studies aimed at enhancing our understanding of clinical parameters related to OCSCC. Two databases were searched, and 27 studies published between 2002 and 2020 were included. The average sample size was 13,776 patients (range 356- 50,896 patients). Four areas of research focus were identified: demographic and socioeconomic status, diagnosis, prognosis, and treatment. This review highlights the impact of age, sex, ethnicity, and socioeconomic status on the prognosis and management of OCSCC, describes the prognostic factors, and details the modalities and indications for neck dissection and adjuvant therapy in OCSCC. In conclusion, the NCDB is a very valuable resource for clinicians and researchers involved in the management of OCSCC, offering an incomparable perspective on a large dataset of patients. Future developments regarding hospital information management, review of data accuracy and completeness, and wider accessibility will help clinicians to improve the care of patients affected by OCSCC.

The sacroiliac joint (SIJ) is a known pain generator that, in severe cases, may require surgical fixation to reduce intra-articular displacements and allow for arthrodesis. The objective of this computational study was to analyze how the number of implants affected SIJ stabilization with patient-specific characteristics such as the pelvic geometry and bone quality. Detailed finite element models were developed to account for three pelvises of differing anatomy. Each model was tested with a normal and low bone density (LD) under two types of loading: compression only and compression with flexion and extension moments. These models were instrumented with one to three cylindrical, threaded and fenestrated implants through a posterior oblique trajectory, requiring less muscle dissection than the more common lateral trajectory used with triangular implants. Compared with the noninstrumented pelvis, the change in range of motion (ROM) and stress distribution were used to characterize joint stabilization. Noninstrumented mobility ranged from 0.86 to 2.55 mm and from 1.37° to 6.11°. Across patient-specific characteristics, the ROM reduction with one implant varied from 3% to 21% for vertical and 15% to 47% for angular displacements. With two implants, the ROM reduction ranged from 12% to 41% for vertical and from 28% to 61% for angular displacements. Three implants, however, did not further improve the joint stability (14% to 42% for vertical and 32% to 63% for angular displacements). With respect to patient characteristics, an LD led to a decreased stabilization and a higher volume of stressed bone (>75% of yield stress). A better understanding of how patient characteristics affect the implant performance could help improve surgical planning of sacroiliac arthrodesis.

Introduction This study aims at identifying mechanical characteristics under bi-axial loading conditions of extracted swine pia mater (PM) and dura and arachnoid complex (DAC). Methods 59 porcine spinal samples have been tested on a bi-axial experimental device with a pre-load of 0.01 N and a displacement rate of 0.05 mm.s−1. Post-processing analysis included an elastic modulus, as well as constitutive model identification for Ogden model, reduced Gasser Ogden Holzapfel (GOH) model, anisotropic GOH model, transverse isotropic and anisotropic Gasser models as well as a Mooney-Rivlin model including fiber strengthening for PM. Additionally, micro-structure of the tissue was investigated using a bi-photon microscopy. Results Linear elastic moduli of 108±40 MPa were found for DAC longitudinal direction, 53±32 MPa for DAC circumferential direction, with a significant difference between directions (p Statement of Significance This study is the first to present biaxial tensile test of pia mater as well as constitutive model comparisons for dura and arachnoid complex tissue based on such tests. Collagen structures observed by semi-quantitative analysis of two photon microscopy confirmed the use of anisotropic Gasser model for pia mater and existence of fenestration. While clear identification of fibre population was not possible in DAC, results from anisotropic Gasser model depicted better fitting on experimental data as per this protocol. Bi-axial mechanical testing allows quasi-static characterization under conditions closr to the physiological context and the results presented could be used for further simulations of physiology. Indeed, the inclusion of meningeal tissue in finite element models will allow more accurate and reliable numerical simulations.

Summary Three deaths following facial impacts in the presence of witnesses and resulting in brain lesions that were visualized only on pathological examination were studied at the forensic medicine institute of Marseille. Craniofacial impacts, even of low intensity, received during brawls may be associated with brain lesions ranging from a simple knock-out to fatal injuries. In criminal cases that are brought to court, even by autopsy it is still difficult to establish a direct link between the violence of the impact and the injuries that resulted in death. During a facial impact, the head undergoes a movement of violent forced hyperextension. Death may thus be secondary to the transmission of forces to the brain, either by a mechanism involving nerve conduction that may be termed a reflex mechanism (for example by vagal hyperstimulation) or by injury to the central nervous system (axonal damage). In such situations, autopsy does not make it possible to determine the cause of death, but only to suspect it in a context of voluntary violence in the presence of witnesses, with or without violent injury observed on external examination or on superficial incisions to determine the extent of bruises or hematoma. Systemic and comprehensive investigation involving pathology and toxicology is essential in any medicolegal case for positive interpretation and discrimination of other causes of death.

Purpose The aim of this study was to show the displacements and strain induced by the supraorbital band advancement during a craniofacial surgery for an anterior plagiocephaly on the orbital bones and the orbital content thanks to a numerical surgical simulation using the finite element method. Methods A three-dimensional (3D) finite element model of a child with an anterior plagiocephaly was entirely created from a tomodensitometry of a patient followed by our Craniofacial Pediatric team. Data of the tomodensitometry were computed with Slicer 3D to re-create the orbit geometry. Mesh production, properties of the model, and simulations of the fronto-orbital advancement were conducted on Hyperworks software (Altair Engineering, Inc., Detroit, MI, USA). Results The resulting 3D Finite Element Model was used to perform the supraorbital advancement simulation. Displacement and strain patterns were studied for orbital bones, oculomotor muscles, and eyeballs. Relative high strain in the both trochlear area and excycloration of the right orbit are among the most interesting results as torsional strabismus as V-pattern strabismus are often described in children with an anterior plagiocephaly. Conclusions This pediatric Finite-Element Model of both orbits of a child with an anterior plagiocephaly showed the impact of the fronto-orbital advancement on the oculomotor system. This model described the relationship between the craniofacial surgery and the strabismus in the unilateral coronal synostosis. The advantages of this model are the many opportunities for improvement, including postoperative period and additional surgical procedures.

International audience; Objective: This study aimed to analyze the morphology of the hypoplasic mandible and its evolution during the growth period to better understand how it differs from the pediatric healthy mandible. Method: Three-dimensional mandibular models of hypoplasic and healthy children aged from 39 gestational weeks to 7 years old were analyzed with a morphometric method including data clustering. Morphological distinctions between pathological and healthy mandibles were highlighted. Bilateral and unilateral mandibular hypoplasia were distinguished. Results: The study sample was composed of 31 hypoplasic children and as many sex- and age-matched healthy children. Morphological distinctions between pathological and healthy mandibles were highlighted only from the first year of life. In bilateral hypoplasia, the overall mandibular dimensions were reduced while there was only a ramus asymmetry in unilateral mandibular hypoplasia (mean ± SD of the difference between the Grp03c and Grp03b subgroups: 6.80 ± 6.37 – P value = 1.64e –3 for the height of the left ramus versus 0.18 ± 4.18 – P value = .82 for the height of the right ramus). Supervised classification trees were built to identify the pathology and discriminate unilateral from bilateral mandibular hypoplasia (prediction rates = 81% and 84%, respectively). Conclusions: Based on a morphometric analysis, we demonstrated that mandibular hypoplasia significantly impacts the mandibular morphology only from the first year of life, with a distinction between bilateral and unilateral hypoplasia.

Background Prosthetic rehabilitation improves the overall quality of life of patients, despite discomfort and medical complications. No quantitative assessment of prosthesis-patient interaction is used in routine protocols and prosthesis quality still results from the manufacturer's know-how. Objective Our objective is to investigate whether pressure can be a relevant factor for assessing socket adequacy. Methods A total of 8 transtibial amputee volunteers took part in this experimental study. The protocol included static standing and 2 minutes walking tests while the stump-to-socket interface pressures were measured. Questionnaires on comfort and pain were also conducted. Results During static standing test, maximum pressures were recorded in the proximal region of the leg, with a peak value reaching 121.1 ± 31.6 kPa. During dynamic tests, maximum pressures of 254.1 ± 61.2 kPa were recorded during the loading phase of the step. A significant correlation was found between the pain score and static maximum recorded pressure (r= 0.81). Conclusions The protocol proposed and evaluated in this study is a repeatable, easy-to-set quantified analysis of the patient to socket interaction while standing and walking. This approach is likely to improve feedback for prosthesis manufacturers and consequently the overall design of prostheses.

Objectives:Numerous tools have been developed to characterize the morphometryof 3D models. The aim of this study was to apply these techniques to better under-stand the morphometric growth pattern of healthy children's mandibles.Material and Methods:The study sample was composed of 480 very young childrenaged from 36 gestational weeks to 7 years old. The sample was divided into threesubsamples according to the development stages of their deciduous dentition. Sev-eral biometric data were collected on 3D mandibular models.Results:There was homothetic growth during the first years of life. Once all decidu-ous teeth were fully erupted, the mandibular corpus warped more independently ofthe ramus, and the inter-individual variability was more pronounced. Throughout thegrowth period, several subgroups could be identified, highlighting the morphologicalgrowth pattern of the mandible.Conclusions:A particular morphogenesis of the mandible during the growth periodwas observed, which was correlated with deciduous dentition development. In youn-ger individuals, this morphological pattern was mainly characterized by the progres-sive closure of the chin symphysis and ramus growth. The tongue movements in theoral space, depending on whether the child was bottle- or breast-fed, may explainthis result. As the children grew older, the mandible widened to create sufficientspace for the developing teeth buds. During the eruption of deciduous dentition, themandible took on various morphologies, which was likely based on the child's sex anddiet. Therefore, we assume that this mandibular morphogenesis is induced by thefunctional strains affecting the mandible during deciduous teeth development.

To evaluate the performance of an early repeated computed tomography (rCT) in initially non-operated patients with blunt bowel and mesenteric injuries (BBMI). This was a monocentric retrospective observational study from 2009 to 2017 of patients with a BBMI on initial CT (iCT). Patients initially non-operated on were scheduled for a rCT within 48 h. Initial CT and rCT diagnostic performance were compared based on a surgical injury prediction score previously described. For statistical analysis, we used the chi-square analyses for paired data (McNemar test). Eighty-four patients (1.9% of trauma) had suspected BBMI on iCT. Among these patients, 22 (26.2%) were initially operated on, 18 (21.4%) were later operated on, and 44 (52.4%) were not operated on. The therapeutic laparotomy rate was 85%. Thirty-four patients initially non-operated on had a rCT. The absolute value of the CT scan score increased for 15 patients (44.1%). The early rCT diagnostic performance, compared with iCT, showed an increase in sensitivity (from 63.6 to 91.7%), in negative predictive value (from 77.4 to 94.7%), and in AUC (from 0.77 to 0.94). In initially non-operated patients with BBMI lesions, the performance of an early rCT improved the sensitivity of lesion detection requiring surgical repair and the security of patient selection for non-operative treatment. • Selective non-operative treatment for hemodynamically stable patients with blunt bowel and/or mesenteric injuries on CT is developing but remains controversial. • An early repeated CT improved the sensitivity of lesion detection requiring surgical repair and the security of patient selection for conservative treatment.

Introduction The authors’ main purpose was to simulate the behavior of a titanium mesh implant (TMI) used to reconstruct the orbital floor under the stress of a blunt trauma. Materials and methods The orbital floor of a previously validated finite element model (FEM) of the human orbit was numerically fractured and reconstructed by a simplified TMI. Data from a CT scan of the head were computed with MICMICS (Materialise, Louvain, Belgium) software to re-create the skull's geometry. The meshing production, the model's properties management and the simulations of blunt traumas of the orbit were conducted on HYPERWORKS® software (Altair Engineering, Detroit, MI, USA). Some of the elements of the orbital floor were selected and removed to model the fracture; these elements were duplicated, their characteristics being changed by those of titanium to create a TMI covering this fracture. A 3D FEM composed of 640,000 elements was used to perform 21 blunt trauma simulations on the reconstructed orbit. Results In 90.4% (19/21) of the tests conducted, the TMI, whether free from any bony attachment or screwed to the orbital rim, has tended to move in the orbit and/or to deform. Discussion In the event of traumatic recurrence, which is not rare, TMIs may deform in a “blow-in” motion and threaten intra-orbital structures.

International audience; Objective: The aim of this study was to analyse the correlations between maternal size, neonatal size, the dimensions of the maternal pelvis and gestational variables. Methods: In this study 131 mother-infant pairs were recruited. We investigate correlation between maternal traits (height, BMI, uterus height), neonatal traits (gestational age, birthweight, head, suboccipito-brematic and abdominal girth) and pelvic variables (conjugate diameter, inter-spinous diameter, sub-pubic angle) collected from computed tomography pelvimetry. Results: We found that the five neonatal traits are significantly inter-correlated. Among maternal traits, height is highly correlated with conjugate and inter-spinous diameters. Subpubic angle is correlated with inter-spinous diameter. Uterus height is correlated with the four neonatal growth traits. Gestational age is correlated with birthweight, head and abdominal girth. Among neonatal and pelvimetry correlations, conjugate diameter is highly correlated with suboccipito-bregmatic girth. Discussion: Matches between gestational age and neonatal traits, and between uterus height and neonatal traits could be related to the process of fetal maturation, orchestrated by the pregnancy clocks. Indeed, the triggering of parturition is supposed to result from the coordination and initiation of 4 clocks (endocrine, fetal membrane, decidual and myometrial) implying fetal organ maturation and fetal membrane senescence. Obstetric dilemma is an evolutionary tradeoff resulting from the conflicting pressures between bipedal locomotion efficiency and the selection for bigger brain size at birth. Correlation between suboccipito-bregmatic girth and conjugate suggests that the more the inlet is sagitally reduced, the smaller suboccipito-bregmatic girth is. Moreover, acquisition of the adult birth canal morphology causes minimal variation at the inlet, compare to the fetus morphology, suggesting that suboccipito-bregmatic girth follows the size of the inlet, but in one-way. Therefore, our interpretation of this pelvic-fetal correlation suggests that the pelvic size seems to be also a constraint to the fetal growth process. This adjustement of fetus size to the birth canal dimensions limits the risk of dystocia and could be interpretated as a remnant signature of the obstetric dilemma in our obstetrical sample.

Background Planimetry of aortic stenosis can be performed when Doppler measurements are unavailable. We sought to evaluate if, as advised in guidelines, the geometric orifice area (GOA) threshold value of 1 cm² was concordant with the threshold of 1 cm² of the effective orifice area (EOA), and the factors influencing the contraction coefficient (EOA/GOA ratio). Methods In an in vitro mock circulatory system, we tested 6 degrees of AS severity (3 severe and 3 non-severe), and 3 levels of flow ( 250 ml/s). The EOA was calculated by Doppler-echocardiography, and the GOA was measured with dedicated software after camera acquisition. Results In all but the very low flow condition, an EOA of 1 cm² corresponded to a GOA of 1.2 cm². The contraction coefficient increased with both the flow and the stenosis severity. For very severe stenoses, the EOA and the GOA were interchangeable. Conclusion As observed in clinical studies, the GOA was larger than the EOA, and a GOA between 1 and 1.2 cm² should not discard the possibility of severe aortic stenosis.

Finite element analysis (FEA) has been widely used to study foot biomechanics and pathological functions or effects of therapeutic solutions. However, development and analysis of such foot modeling is complex and time-consuming. The purpose of this study was therefore to propose a method coupling a FE foot model with a model order reduction (MOR) technique to provide real-time analysis of the dynamic foot function. A generic and parametric FE foot model was developed and dynamically validated during stance phase of gait. Based on a design of experiment of 30 FE simulations including four parameters related to foot function, the MOR method was employed to create a prediction model of the center of pressure (COP) path that was validated with four more random simulations. The four predicted COP paths were obtained with a 3% root-mean-square-error (RMSE) in less than 1 s. The time-dependent analysis demonstrated that the subtalar joint position and the midtarsal joint laxity are the most influential factors on the foot functions. These results provide additionally insight into the use of MOR technique to significantly improve speed and power of the FE analysis of the foot function and may support the development of real-time decision support tools based on this method.

Objective The AMBUVASC trial evaluated the cost effectiveness of outpatient vs. inpatient hospitalisation for endovascular repair of lower extremity arterial disease (LEAD). Methods AMBUVASC was a national multicentre, prospective, randomised controlled trial conducted in nine public and two private French centres. The primary endpoint was the incremental cost effectiveness ratio (ICER), defined by cost per quality adjusted life year (QALY). Analysis was conducted from a societal perspective, excluding indirect costs, and considering a one month time horizon. Results From 16 February 2016 to 29 May 2017, 160 patients were randomised (80 per group). A modified intention to treat analysis was performed with 153 patients (outpatient hospitalisation: n = 76; inpatient hospitalisation: n = 77). The patients mainly presented intermittent claudication (outpatient arm: 97%; inpatient arm: 92%). Rates of peri-operative complications were 20% (15 events) and 18% (14 events) for the outpatient and inpatient arms respectively (p = .81). Overall costs (difference: €187.83; 95% confidence interval [CI] −275.68–651.34) and QALYs (difference: 0.00277; 95% CI –0.00237 – 0.00791) were higher for outpatients due to more re-admissions than the inpatient arm. The mean ICER was €67 741 per QALY gained for the base case analysis with missing data imputed using multiple imputation by predictive mean matching. The outpatient procedure was not cost effective for a willingness to pay of €50 000 per QALY and the probability of being cost effective was only 59% for a €100 000/QALY threshold. Conclusion Outpatient hospitalisation is not cost effective compared with inpatient hospitalisation for endovascular repair of patients with claudication at a €50 000/QALY threshold.

Background The spinal meninges play a mechanical protective role for the spinal cord. Better knowledge of the mechanical behavior of these tissues wrapping the cord is required to accurately model the stress and strain fields of the spinal cord during physiological or traumatic motions. Then, the mechanical properties of meninges along the spinal canal are not well documented. The aim of this study was to quantify the elastic meningeal mechanical properties along the porcine spinal cord in both the longitudinal direction and in the circumferential directions for the dura-arachnoid maters complex (DAC) and solely in the longitudinal direction for the pia mater. This analysis was completed in providing a range of isotropic hyperelastic coefficients to take into account the toe region. Methods Six complete spines (C0 – L5) were harvested from pigs (2–3 months) weighing 43±13 kg. The mechanical tests were performed within 12 h post mortem. A preload of 0.5 N was applied to the pia mater and of 2 N to the DAC samples, followed by 30 preconditioning cycles. Specimens were then loaded to failure at the same strain rate 0.2 mm/s (approximately 0.02/s, traction velocity/length of the sample) up to 12 mm of displacement. Results The following mean values were proposed for the elastic moduli of the spinal meninges. Longitudinal DAC elastic moduli: 22.4 MPa in cervical, 38.1 MPa in thoracic and 36.6 MPa in lumbar spinal levels; circumferential DAC elastic moduli: 20.6 MPa in cervical, 21.2 MPa in thoracic and 12.2 MPa in lumbar spinal levels; and longitudinal pia mater elastic moduli: 18.4 MPa in cervical, 17.2 MPa in thoracic and 19.6 MPa in lumbar spinal levels. Discussion The variety of mechanical properties of the spinal meninges suggests that it cannot be regarded as a homogenous structure along the whole length of the spinal cord.

Some young patients with a significant skeletal shift with a strong morpho-aesthetic and psychological impact may require surgical correction during their growth. A good understanding of facial growth, the different treatment options and the effects of surgery on the post-operative growth pattern will allow the practitioner to use the technique most suited to each of his patients and improve long-term treatment outcomes. So-called « interceptive » surgery may therefore be considered in cases of severe skeletal dysmorphism of secondary or functional origin. It will lead to early normalization with the immediate consequence of breaking the « dysmorpho-dysfunctional » spiral.

To resolve the various types of biological ice nuclei (IN) with atmospheric models, an extension of the empirical parameterization (EP) (Phillips et al. 2008; 2013) is proposed to predict the active IN from multiple groups of primary biological aerosol particles (PBAPs). Our approach is to utilize coincident observations of PBAP sizes, concentrations, biological composition, and ice-nucleating ability. The parameterization organizes the PBAPs into five basic groups: fungal spores, bacteria, pollen, viral particles, plant/animal detritus, algae, and their respective fragments. This new biological component of the EP was constructed by fitting predicted concentrations of PBAP IN to those observed at the Amazon Tall Tower Observatory (ATTO) site located in the central Amazon. The fitting parameters for pollen and viral particles, plant/animal detritus, which are much less active as IN than fungal and bacterial groups, are constrained based on their ice nucleation activity from the literature. The parameterization has empirically derived dependencies on the surface area of each group (except algae), and the effects of variability in their mean sizes and number concentrations are represented via their influences on the surface area. The concentration of active algal IN is estimated from literature-based measurements.Predictions of this new biological component of the EP are consistent with previous laboratory and field observations not used in its construction. The EP scheme was implemented in a 0D parcel model. It confirms that biological IN account for most of the total IN activation at temperatures warmer than −20°C and at colder temperatures dust and soot become increasingly more important to ice nucleation.

No specific performance assessment scales have been reported in laparoscopic liver resection. This study aimed at developing an objective scale specific for the assessment of technical skills for wedge resection in anterior segments (WRAS) and left lateral sectionectomy (LLS). A laparoscopic liver skills scale (LLSS) was developed using a hierarchical task analysis. A Delphi method obtained consensus among five international experts on relevant steps that should be included into the LLSS for assessment of operative performances. The consensus was predefined using Cronbach’s alpha > 0.80. A semi-structured review extracted 15 essential subtasks for full laparoscopic WRAS and LLS for evaluation in the Delphi survey. Two rounds of the survey were conducted. Three over 15 subtasks did not reach the predefined level of consensus. Based on the expert’s comments, 13 subtasks were reformulated, 4 subtasks were added, and a revised skills scale was developed. After the 2nd round survey (Cronbach’s alpha 0.84), 19 subtasks were adopted. The LLSS was composed of three main parts: patient positioning and intraoperative preparation (task 1 to 8), the core part of the WRAS and LLS procedure (tasks 9 to 14), and completion of procedure (task 15 to 19). The LLSS was developed for measuring the skill set for the education of safe and secure laparoscopic WRAS and LLS procedures in a dedicated training program. After validation, this scale could be also used as an assessment tool in the operating room and extrapolated as an operative roadmap to other complex procedures.

International audience; Mitral regurgitation (MR) is the second mostcommon valve disease in industrialized countries. Despite itshigh prevalence, little is known about its impact on the flowdynamics in the left ventricle (LV). Because of the interde-pendence between valvular function and hemodynamics inthe heart chambers, an exploration of the dynamics in the LVcould lead to a diagnosis of MR. Thisin vitrostudy aimed todevelop an advanced left heart simulator capable of repro-ducing several conditions of MR and to evaluate their impacton the LV flow dynamics in terms of flow structures andviscous energy dissipation (VED).Methods—A simulator, previously developed to test mechan-ical and biological valves, was upgraded with an originalanatomically-shaped mitral valve made from a hydrogel. Thevalve can be used in healthy or pathological configurations.The nature and severity of the disease was controlled byapplying specific strain to the chordae. In this study, inaddition to a healthy condition, two different severities ofMR were investigated: moderate MR and severe MR. Planartime-resolved particle image velocimetry measurements wereperformed in order to evaluate the velocity field in the LVand the VED induced by each condition.Results—Our results showed that MR led to flow distur-bances in the LV that were characterized by an increase inmitral inflow velocity and by elevated values of VED.Interestingly VED increased in proportion to the severityof MR and with a dissipation predominating during systole.Conclusion—Considering these results, the introduction ofnew parameters based on LV VED could provide crucialinformation regarding the coupling between the mitral valveand the LV and allow for a better stratification of patientswith

International audience

This report highlights the utility of MatriStem Surgical Matrix Thick UBM™ (rebranded as Gentrix® ACell, Inc), a decellularised urinary bladder extracellular matrix in the reconstruction of a post-oncological maxillectomy defect. In utilising this biological construct to serve as a biological dressing, our patient underwent complete mucosalisation of his surgical site without the development of an oroantral fistula and with adequate maxillary vestibule to allow for definitive oral rehabilitation with a removable partial denture.

International audience; PurposeTo explore the feasibility of dynamic susceptibility contrast MRI at 7 Tesla for human spinal cord perfusion mapping and fill the gap between brain and spinal cord perfusion mapping techniques.MethodsAcquisition protocols for high‐resolution single shot EPI in the spinal cord were optimized for both spin‐echo and gradient‐echo preparations, including cardiac gating, acquisition times and breathing cycle recording. Breathing‐induced MRI signal fluctuations were investigated in healthy volunteers. A specific image‐ and signal‐processing pipeline was implemented to address them. Dynamic susceptibility contrast was then evaluated in 3 healthy volunteers and 5 patients. Bolus depiction on slice‐wise signal within cord was investigated, and maps of relative perfusion indices were computed.ResultsSignal fluctuations were increased by 1.9 and 2.3 in free‐breathing compared to apnea with spin‐echo and gradient‐echo, respectively. The ratio between signal fluctuations and bolus peak in healthy volunteers was 5.0% for spin‐echo and 3.8% for gradient‐echo, allowing clear depiction of the bolus on every slice and yielding relative blood flow and volume maps exhibiting the expected higher perfusion of gray matter. However, signal fluctuations in patients were increased by 4 in average (using spin‐echo), compromising the depiction of the bolus in slice‐wise signal. Moreover, 3 of 18 slices had to be discarded because of fat‐aliasing artifacts.ConclusionDynamic susceptibility contrast MRI at 7 Tesla showed great potential for spinal cord perfusion mapping with a reliability never achieved thus far for single subject and single slice measurements. Signal stability needs to be improved in acquisition conditions associated with patients; guidelines to achieve that have been identified and shared.

International audience; Defects affecting the anterior wall of the tympanal bone can result from trauma, infection, neoplasm or previous local surgery. An anatomic variation, namely the persistence of the foramen tympanicum, can also be encountered. When symptomatic, surgical reconstruction may be indicated. The aim of this study was to identify the surgical treatments of symptomatic foramen tympanicum found in the literature and detail our innovative reconstruction technique. A bibliographic research was conducted in PubMed database in March 2020, without time limitation. Papers dealing with surgical management of a foramen tympanicum were included. Data collected were the publication date, the number of patients, their age and gender, the symptoms and the surgical treatment performed. We report, in addition, the case of a symptomatic persistent foramen tympanicum in a 30-year-old man with a follow-up of 18-months. A total of 17 studies (n=23 patients) were included for analysis. The main reconstruction techniques were, in equal proportion, cartilage graft (30%) and insertion of a titanium mesh (30%). We carried out an iliac crest bone graft using a preauricular approach on a patient suffering from chronic tinnitus and fullness in the left ear resulting from a persistent foramen tympanicum, confirmed by clinical and radiological examinations. It allowed the complete resolution of symptoms and no complication such as temporomandibular ankylosis occurred. Based on the review of the literature, we believe this technique has the advantage of providing durable reconstruction thanks to osseointegration.

Several approaches have been described for the surgical management of condylar fractures. Although there is no consensus on the best surgical technique, the retromandibular approach appears to be the most common reported in the literature. This approach is traditionally performed via a retromandibular incision and a transparotid route. An alternative technique to this approach entails a subparotid passage with the gland lifted antero-superiorly and no intraglandular dissection. This modification has been designed to reduce the risk of direct injury of the facial nerve branches as well as the risk of post-operative salivary fistula. The purpose of this technical report was to provide a "step-by-step" description of the retromandibular subparotid approach as performed in our department with particular emphasis on the relevant anatomically critical structures.

Prone positioning is an adjuvant therapy used to treat COVID-19 pneumonia complicated by acute respiratory distress syndrome. However, prolonged pressure on facial skin at the level of the bony structures may be responsible for facial pressure ulcers. In the context of severe COVID-19 pneumonia, we hypothesized that hypoxemia, microvascular injury and thrombosis can increase the risk of pressure ulcers. We described two cases in order to emphasize the risk of facial pressure ulcers as a result of prone positioning, so as to discuss their physiopathology and highlight the importance of appropriate preventive measures.

International audience; BackgroundDegenerative Cervical Myelopathy results from spine degenerations narrowing the spinal canal and inducing cord compressions. Prognosis is challenging. This study aimed at simulating typical spinal cord compressions observed in patients with a realistic model to better understand pathogenesis for later prediction of patients' evolution.MethodsA 30% reduction in cord cross-sectional area at C5-C6 was defined as myelopathy threshold based on Degenerative Cervical Myelopathy features from literature and MRI measurements in 20 patients. Four main compression types were extracted from MRIs and simulated with a comprehensive three-dimensional finite element spine model. Median diffuse, median focal and lateral types were modelled as disk herniation while circumferential type additionally involved ligamentum flavum hypertrophy. All stresses were quantified along inferior-superior axis, compression development and across atlas-defined spinal cord regions.FindingsAnterior gray and white matter globally received the highest stress while lateral pathways were the least affected. Median diffuse compression induced the highest stresses. Circumferential type focused stresses in posterior gray matter. Along inferior-superior axis, those two types showed a peak of constraints at compression site while median focal and lateral types showed lower values but extending further.InterpretationMedian diffuse type would be the most detrimental based on stress amplitude. Anterior regions would be the most at risk, except for circumferential type where posterior regions would be equally affected. In addition to applying constraints, ischemia could be a significant component explaining the early demyelination reported in lateral pathways. Moving towards patient-specific simulations, biomechanical models could become strong predictors for degenerative changes.

Motorcycle to vehicle collision is one of the most common accidents in the world and usually leads to serious or fatal head injuries to motorcyclists. This study aims to investigate the influences of impact scenarios and vehicle front-end design parameters on head injury risk of the motorcyclist. Five general vehicle types and different impact scenarios were selected for a parametric analysis. Impact scenarios were set according to ISO, 13232 regulation considering impact angles and impact speeds. Five vehicle types of Sedan, MPV (Multi-Purpose Vehicle), SUV (Sport Utility Vehicle), EV (Electric Vehicle) and 1-Box vehicle were included. HIC15 (Head Injury Criterion), head angular acceleration and CSDM (Cumulative Strain Damage Measure) were calculated to evaluate head injury risk of the motorcyclist. The results show that the critical impact speed for HIC15 and head angular acceleration was around 15 m/s, while the critical speed for CSDM was approximately 10 m/s. Impact angle of 45° show extremely high injury risk to the motorcyclist head. Bonnet leading edge height and its combination with other parameter present high influences on motorcyclist head injuries, and the increasing the bonnet leading edge height can potentially reduce head injury risk of motorcyclists. In summary, the present research results provide some theoretic bases for determining the test speed in motorcycle-vehicle crash regulation and design consideration for typical vehicle front end shape.

Virtual finite element human body models have been widely used in biomedical engineering, traffic safety injury analysis, etc. Soft tissue modeling like skeletal muscle accounts for a large portion of a human body model establishment, and its modeling method is not enough explored. The present study aims to investigate the compressive properties of skeletal muscles due to different species, loading rates and fiber orientations, in order to obtain available parameters of specific material laws as references for building or improving the human body model concerning both modeling accuracy and computational cost. A series of compressive experiments of skeletal muscles were implemented for human gastrocnemius muscle, bovine and porcine hind leg muscle. To avoid long-time preservation effects, all experimental tests were carried out in 24 h after that the samples were harvested. Considering computational cost and generally used in the previous human body models, one-order hyperelastic Ogden model and three-term simplified viscoelastic quasi-linear viscoelastic (QLV) were selected for numerical analysis. Inverse finite element analysis was employed to obtain corresponding material parameters. With good fitting records, the simulation results presented available material parameters for human body model establishment, and also indicated significant differences of muscle compressive properties due to species, loading rates and fiber orientations. When considering one-order Ogden law, it is worthy of noting that the inversed material parameters of the porcine muscles are similar to those of the human gastrocnemius regardless of fiber orientations. In conclusion, the obtained material parameters in the present study can be references for global human body and body segment modeling.

International audience; Celiac disease is an immune-mediated enteropathy associated with malabsorptive syndrome and fat-soluble vitamin deficiencies. Celiac disease affects 1% of individuals but is largely underdiagnosed, as its multifaceted clinical presentations create challenging diagnostic scenarios. With the rise of the obesity epidemic, doctors are increasingly seeing celiac disease patients with overweight or obesity, which raises the question of bariatric surgery. However, few studies so far have investigated bariatric surgery in this patient population. Here, we provide a comprehensive review of the literature on celiac disease, its nutritional consequences and complications, and we discuss the possible impact of bariatric surgery on weight loss, nutritional deficiencies, response to gluten-free diet, and long-term post-operative complications. We also review the effect of bariatric surgery on the incidence of celiac disease.

Strangulation is a violent act which can be lethal and is often studied in forensic context. The neck includes several anatomical elements that can evolve with aging. We therefore created a numerical human neck model including the main anatomical elements and simulated one-handed grip strangulation cases. In addition, we created 3 models each representing age groups: 20–30 years old, 30–50 years old and over 50 years old. The main changes between the different age groups are the ossification of the cartilages and the muscles mechanical properties. Several initial and boundary conditions have been tested to perform a realistic simulation of one-handed grip strangulation. Stress analysis and fracture observation were compared with the grip strength of an average man, 552 N, to look at the intentionality of the gesture. In each age group, the results show no model fracture for a force of 552 N. It is necessary to reach a minimum of 1406 N before observing a first fracture on the hyoid bone. However, it is possible to get stresses on the hyoid bone and on the thyroid cartilage way before 552 N. It thus appears that the force created by one-handed grip strangulation is not sufficient to cause fractures of the bony elements of the neck, but it remains sufficient to compress the larynx and at least reduce airflow.