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Finite element analysis (FEA) is a fundamental tool that can be used in the orthopaedic world to simulate and analyze the behaviour of different surgical procedures. It is important to be aware that removing more than 20% of the meniscus could increase the shear stress in the cartilage and enlarge the risk of knee joint degeneration. In this fact, the maximal shear stress value in the medial cartilage increased up to 225% from 0.15 MPa to 0.5 MPa after medial meniscectomy. Also, meniscal root repair can improve meniscal biomechanics and potentially reduce the risk of osteoarthritis, even in cases of a loose repair. FEA has been used to better understand the biomechanical role of cruciate ligaments in the knee joint. ACLr with bone-patellar tendon-bone graft at 60 N of pretension and double-bundle PCLr were closer to that of a native knee in terms of biomechanics. The addition of a lateral extra-articular augmentation technique can reduce 50% of tibial translation and internal rotation, protecting the graft and minimizing the risk of re-rupture. Interestingly, anatomic and non-anatomic medial patellofemoral ligament reconstruction increased the pressure applied to the patellofemoral joint by increasing patellar contact pressure to 0.14 MPa at 30° of knee flexion using the semitendinosus as a graft. After all the advances in medical imaging technologies, future studies should take into consideration patient-specific data on both anatomy and mechanics, in order to better personalize the experimental model.

Abstract An unusual case of left internal thoracic artery (ITA) origin from the thyrocervical trunk (TCT) was detected during routine cadaver dissection. The variability of origin and course of ITA has less or more frequently been documented in the literature. However, the ITA origin from the TCT on the left side has been detected less commonly, making its dissection and preparation during coronary artery bypass grafting surgery more difficult. We discuss the ITA origin and course variability as well as clinical significance of the present variant, reviewing the relative literature. The objective of our study is to exhibit a rare ITA origin in order to provide a more accurate knowledge of such variations.

Abstract Over the recent years, an increased alertness for thorough knowledge of anatomical variants with clinical significance has been recorded in order to minimize the risks of surgical complications. We report a rare case of bilateral strap-like sternalis muscle of the anterior chest wall in a female cadaver. Its presence may evoke alterations in the electrocardiogram or confuse a routine mammography. The incidental finding of a sternalis muscle in mammography, CT, and MRI studies must be documented in a patient's medical records as it can be used as a pedicle flap or flap microvascular anastomosis during reconstructive surgery of the anterior chest wall, head and neck, and breast. Moreover, its presence may be misdiagnosed as a wide range of benign and malignant anterior chest wall lesions and tumors.

Abstract Introduction Although variations in the origin of the testicular artery are not uncommon, few reports about a high origin from the abdominal aorta exist in the literature. We discuss the case of a high origin of the testicular artery, its embryology, classification systems, and its clinical significance. Case presentation We report a very rare case of high origin of the left testicular artery in a 68-year-old Caucasian male cadaver. The artery originated from the anterolateral aspect of the abdominal aorta, 2 cm cranially to the ipsilateral renal artery. Approximately 1 cm after its origin, it branched off into the inferior suprarenal artery. During its course, the artery crossed anterior to the left renal artery. Conclusions A knowledge of the variant origin of the testicular artery is important during renal and testicular surgery. The origin and course must be carefully identified in order to preserve normal blood circulation and prevent testicular atrophy. A reduction in gonadal blood flow may lead to varicocele under circumstances. A knowledge of this variant anatomy may be of interest to radiologists and helpful in avoiding diagnostic errors.

Background: Alzheimer's disease (AD) may present with pure (typical or atypical) and mixed phenotypes, sometimes causing difficulties in (differential) diagnosis. In order to achieve a diagnostic accuracy as high as possible, the diagnosis of AD during life depends on various biomarkers, including the cerebrospinal fluid (CSF) biomarkers. Methods: Classical CSF AD biomarkers were determined in a total of 61 patients, classified as both beta amyloid- and tau-positive A+T+ (or A+T1+ according to the recently revised Alzheimer Association criteria for diagnosis and staging of AD). Twenty one of these patients fulfilled the criteria for mixed AD (mixed with Lewy bodies, cerebrovascular disease, or normal pressure hydrocephalus), whilst 40 had pure AD. Results: Patients did not differ with respect to gender, education, disease duration, and cognitive status. After controlling for confounding factors, no difference was observed between mixed and pure AD groups in Aβ42 or Aβ42/Aβ40 levels. Although by definition, patients of both groups had abnormal (increased) levels of phospho-tau181, the mixed AD group presented with lower (less abnormal) levels of phospho-tau181 and total tau as compared to the pure group. Conclusions: In patients with AD of comparable cognitive status, mixed AD cases may present with lower levels of tau proteins and, if close to the cut-off values, diagnostic uncertainty may be increased. [ABSTRACT FROM AUTHOR]

ImportanceCerebral amyloid-β aggregation is an early event in Alzheimer disease (AD). Understanding the association between amyloid aggregation and cognitive manifestation in persons without dementia is important for a better understanding of the course of AD and for the design of prevention trials.ObjectiveTo investigate whether amyloid-β aggregation is associated with cognitive functioning in persons without dementia.Design, setting, and participantsThis cross-sectional study included 2908 participants with normal cognition and 4133 with mild cognitive impairment (MCI) from 53 studies in the multicenter Amyloid Biomarker Study. Normal cognition was defined as having no cognitive concerns for which medical help was sought and scores within the normal range on cognitive tests. Mild cognitive impairment was diagnosed according to published criteria. Study inclusion began in 2013 and is ongoing. Data analysis was performed in January 2017.Main outcomes and measuresGlobal cognitive performance as assessed by the Mini-Mental State Examination (MMSE) and episodic memory performance as assessed by a verbal word learning test. Amyloid aggregation was measured with positron emission tomography or cerebrospinal fluid biomarkers and dichotomized as negative (normal) or positive (abnormal) according to study-specific cutoffs. Generalized estimating equations were used to examine the association between amyloid aggregation and low cognitive scores (MMSE score ≤27 or memory z score≤-1.28) and to assess whether this association was moderated by age, sex, educational level, or apolipoprotein E genotype.ResultsAmong 2908 persons with normal cognition (mean [SD] age, 67.4 [12.8] years), amyloid positivity was associated with low memory scores after age 70 years (mean difference in amyloid positive vs negative, 4% [95% CI, 0%-7%] at 72 years and 21% [95% CI, 10%-33%] at 90 years) but was not associated with low MMSE scores (mean difference, 3% [95% CI, -1% to 6%], P = .16). Among 4133 patients with MCI (mean [SD] age, 70.2 [8.5] years), amyloid positivity was associated with low memory (mean difference, 16% [95% CI, 12%-20%], P

ImportanceCerebral amyloid-β aggregation is an early pathological event in Alzheimer disease (AD), starting decades before dementia onset. Estimates of the prevalence of amyloid pathology in persons without dementia are needed to understand the development of AD and to design prevention studies.ObjectiveTo use individual participant data meta-analysis to estimate the prevalence of amyloid pathology as measured with biomarkers in participants with normal cognition, subjective cognitive impairment (SCI), or mild cognitive impairment (MCI).Data sourcesRelevant biomarker studies identified by searching studies published before April 2015 using the MEDLINE and Web of Science databases and through personal communication with investigators.Study selectionStudies were included if they provided individual participant data for participants without dementia and used an a priori defined cutoff for amyloid positivity.Data extraction and synthesisIndividual records were provided for 2914 participants with normal cognition, 697 with SCI, and 3972 with MCI aged 18 to 100 years from 55 studies.Main outcomes and measuresPrevalence of amyloid pathology on positron emission tomography or in cerebrospinal fluid according to AD risk factors (age, apolipoprotein E [APOE] genotype, sex, and education) estimated by generalized estimating equations.ResultsThe prevalence of amyloid pathology increased from age 50 to 90 years from 10% (95% CI, 8%-13%) to 44% (95% CI, 37%-51%) among participants with normal cognition; from 12% (95% CI, 8%-18%) to 43% (95% CI, 32%-55%) among patients with SCI; and from 27% (95% CI, 23%-32%) to 71% (95% CI, 66%-76%) among patients with MCI. APOE-ε4 carriers had 2 to 3 times higher prevalence estimates than noncarriers. The age at which 15% of the participants with normal cognition were amyloid positive was approximately 40 years for APOE ε4ε4 carriers, 50 years for ε2ε4 carriers, 55 years for ε3ε4 carriers, 65 years for ε3ε3 carriers, and 95 years for ε2ε3 carriers. Amyloid positivity was more common in highly educated participants but not associated with sex or biomarker modality.Conclusions and relevanceAmong persons without dementia, the prevalence of cerebral amyloid pathology as determined by positron emission tomography or cerebrospinal fluid findings was associated with age, APOE genotype, and presence of cognitive impairment. These findings suggest a 20- to 30-year interval between first development of amyloid positivity and onset of dementia.

Idiopathic normal-pressure hydrocephalus (iNPH) is a clinic-radiological neurological syndrome presenting with cognitive deficits, gait disturbances and urinary incontinence. It often coexists with Alzheimer's disease (AD). Due to the reversible nature of iNPH when promptly treated, a lot of studies have focused on possible biomarkers, among which are cerebrospinal fluid (CSF) biomarkers. The aim of the present study was to determine the rate of beta-amyloid pathology and AD co-pathology by measuring AD CSF biomarkers, namely, amyloid beta with 42 and 40 amino acids (Aβ42), the Aβ42/Aβ40 ratio, total Tau protein (t-Tau) and phosphorylated Tau protein at threonine 181 (p-Tau), in a cohort of iNPH patients, as well as to investigate the possible associations among CSF biomarkers and iNPH neuropsychological profiles. Fifty-three patients with iNPH were included in the present study. CSF Aβ42, Aβ40, t-Tau and p-Tau were measured in duplicate with double-sandwich ELISA assays. The neuropsychological evaluation consisted of the Mini-Mental State Examination, Frontal Assessment Battery, Five-Word Test and CLOX drawing tests 1 and 2. After statistical analysis, we found that amyloid pathology and AD co-pathology are rather common in iNPH patients and that higher values of t-Tau and p-Tau CSF levels, as well as the existence of the AD CSF profile, are associated with more severe memory impairment in the study patients. In conclusion, our study has confirmed that amyloid pathology and AD-co-pathology are rather common in iNPH patients and that CSF markers of AD pathology and t-Tau are associated with a worse memory decline in these patients. [ABSTRACT FROM AUTHOR]

Objective: Mucoepidermoid carcinomas (MEC) of the larynx account for less than 1% of all laryngeal tumors. The unique features and clinical behavior of these rare entities remain unknown. To fill this knowledge gap, we performed a scoping review of every reported case of laryngeal MEC to study the clinical behavior and the treatment modalities in this rare entity. Review Methods: We followed the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses extension for scoping reviews (PRISMA‐ScR) statement. Data Sources: MedLine, Google Scholar, and Science Direct databases were searched to identify eligible studies. Results: We concluded with 25 studies and overall 66 cases. Our study revealed that the average age of cases was 55.7 years, and the range was from 12 to 81 years, with younger onset in females. Supraglottic (60%) is the most common subsite of laryngeal MEC s followed by glottis (27.3%). Supraglottic carcinomas frequently present with metastatic neck disease at the time of the initial diagnosis and require more extensive surgical approaches. Surgery with negative surgical margins seems to be the cornerstone in the treatment of MEC. Radiation therapy has not been tested widely as monotherapy but is considered a useful adjuvant modality. Conclusion: This study suggests that negative surgical margins seem to be associated to higher disease control rate and that high‐grade supraglottic cases likely benefit from addressing neck disease simultaneously. Level of Evidence: NA Laryngoscope, 134:2578–2584, 2024 [ABSTRACT FROM AUTHOR]