Thoracic outlet syndrome: A neurological and vascular disorder

Thoracic outlet syndrome (TOS) is a condition arising from compression of the subclavian vessels and/or brachial plexus as the structures travel from the thoracic outlet to the axilla. Despite the significant pathology associated with TOS, there remains some general disagreement among experts on the specific anatomy, etiology, and pathophysiology of the condition, presumably because of the wide variation in symptoms that manifest in presenting patients, and because of lack of a definitive gold standard for diagnosis. Symptoms associated with TOS have traditionally been divided into vascular and neurogenic categories, a distinction based on the underlying structure(s) implicated. Of the two, neurogenic TOS (nTOS) is more common, and typically presents as compression of the brachial plexus; primarily, but not exclusively, involving its lower trunk. Vascular TOS (vTOS) usually involves compression of the vessel, most commonly the subclavian artery or vein, or is secondary to thrombus formation in the venous vasculature. Any anatomical anomaly in the thoracic outlet has the potential to predispose a patient to TOS. Common anomalies include variations in the insertion of the anterior scalene muscle (ASM) or scalenus minimus muscle, the presence of a cervical rib or of fibrous and muscular bands, variations in insertion of pectoralis minor, and the presence of neurovascular structures, which follow an atypical course. A common diagnostic technique for vTOS is duplex imaging, which has generally replaced more invasive angiographic techniques. In cases of suspected nTOS, electrophysiological nerve studies and ASM blocks provide guidance when screening for patients likely to benefit from surgical decompression of TOS. Surgeons generally agree that the transaxillary approach allows the greatest field of view for first rib excision to relieve compressed vessels. Alternatively, a supraclavicular approach is favored for scalenotomies when the ASM impinges on surrounding structures. A combined supraclavicular and infraclavicular approach is preferred when a larger field of view is required. The future of TOS management must emphasize the improvement of available diagnostic and treatment techniques, and the development of a consensus gold standard for diagnosis. Helical computed tomography offers a three‐dimensional view of the thoracic outlet, and may be valuable in the detection of anatomical variations, which may predispose patients to TOS. This review summarizes the history of TOS, the pertinent clinical and anatomical presentations of TOS, and the commonly used diagnostic and treatment techniques for the condition. Clin. Anat. 27:724–732, 2014. © 2013 Wiley Periodicals, Inc.     

Comparison between Steroid Injection and Stretching Exercise on the Scalene of Patients with Upper Extremity Paresthesia: Randomized Cross-Over Study

PurposeTo compare the therapeutic effects on upper extremity paresthesia of intra-muscular steroid injections into the scalene muscle with those of stretching exercise only.ResultsAfter two weeks, there was a significant decrease of the visual analog scale score of treatment effect compared with baseline in both groups (6.90 to 2.85 after injection and 5.65 to 4.05 after stretching exercise, p<0.01). However, injection resulted in greater improvements than stretching exercise (p<0.01). The number of patients with successful treatment, defined as >50% reduction in post-treatment visual analog scale, was 18 of 20 (90.0%) after injection, compared to 5 of 20 (25.0%) after stretching exercise. There were no cases of unintended brachial plexus block after injection.ConclusionUltrasound-guided steroid injection or stretching exercise of scalene muscles led to reduced upper extremity paresthesia in patients who present with localized tenderness in the scalene muscle without electrodiagnostic test abnormalities, although injection treatment resulted in more improvements. The results suggest that symptoms relief might result from injection into the muscle alone not related to blockade of the brachial plexus.     

A morphometric study on the superficial palmar arch of the hand

The vascular anatomy of the hand is a complex and challenging area and has been the subject of many studies. Knowledge of the vascular patterns and diameters of the hand gained more importance with improvements in microsurgical techniques in reconstructive hand surgery. We evaluated 50 hands (26 left, 24 right) of 26 formalin preserved cadavers to determine the superficial palmar arch, its branches and contributing vessels with special attention to the diameters. The symmetry of the types was also evaluated in detail for the first time in the literature. Measurements were made with the help of a digital caliper. The diameters of the ulnar, radial and median arteries were taken at the level of the wrist while the common palmar digital arteries, hypothenar branches and the superficial palmar branch of the radial artery were measured at their origin. Two types of superficial palmar arch were found and defined as complete (43/50 hands) and incomplete arches (7/50 hands). The complete arches were divided into four subgroups and incomplete arches into three subgroups. Most cases were found at the complete AI group (17 hands). Comparison of the arterial diameters showed the ulnar artery was the dominant vessel of the palm. The diameters of the common palmar digital arteries were not different with regard to complete or incomplete arches and between both sides. It looks safe to sacrifice one of the radial or ulnar arteries in some arterial interventions including radial artery cannulation, radial forearm flap and radial or ulnar artery harvesting for bypass grafting if the arch is complete. But we still recommend the noninvasive tests like modified Allen test or Doppler ultrasonography, before performing an invasive arterial intervention. We propose the radiologists to incorporate the median artery into the Doppler dynamic test in particular the existence or the absence of anastomoses between radial and ulnar arteries.This study was accepted as an oral presentation in the “IX National Congress of Anatomists, 7–10 September 2005, Kusadasi, Turkey”     

Potential sites of compression of tibial nerve branches in foot: A cadaveric and imaging study

Hypertrophy of abductor hallucis muscle is one of the reported causes of compression of tibial nerve branches in foot, resulting in tarsal tunnel syndrome. In this study, we dissected the foot (including the sole) of 120 lower limbs in 60 human cadavers (45 males and 15 females), aged between 45 and 70 years to analyze the possible impact of abductor hallucis muscle in compression neuropathy of tibial nerve branches. We identified five areas in foot, where tibial nerve branches could be compressed by abductor hallucis. Our findings regarding three of these areas were substantiated by clinical evidence from ultrasonography of ankle and sole region, conducted in the affected foot of 120 patients (82 males and 38 females), aged between 42 and 75 years, who were referred for evaluation of pain and/or swelling in medial side of ankle joint with or without associated heel and/or sole pain. We also assessed whether estimation of parameters for the muscle size could identify patients at risk of having nerve compression due to abductor hallucis muscle hypertrophy. The interclass correlation coefficient for dorso‐planter thickness of abductor hallucis muscle was 0.84 (95% CI, 0.63–0.92) and that of medio‐lateral width was 0.78 (95% CI, 0.62–0.88) in the imaging study, suggesting both are reliable parameters of the muscle size. Receiver operating characteristic curve analysis showed, if ultrasonographic estimation of dorso‐plantar thickness is >12.8 mm and medio‐lateral width > 30.66 mm in patients with symptoms of nerve compression in foot, abductor hallucis muscle hypertrophy associated compression neuropathy may be suspected. Clin. Anat. 26:768–779, 2013. © 2012 Wiley Periodicals, Inc.     

HTAD patient pathway: Strategy for diagnostic work-up of patients and families with (suspected) heritable thoracic aortic diseases (HTAD). A statement from the HTAD working group of VASCERN

Heritable thoracic aortic diseases (HTAD) are rare pathologies associated with thoracic aortic aneurysms and dissection, which can be syndromic or non-syndromic. They may result from genetic defects. Associated genes identified to date are classified into those encoding components of the (a) extracellular matrix (b) TGFβ pathway and (c) smooth muscle contractile mechanism. Timely diagnosis allows for prompt aortic surveillance and prophylactic surgery, hence improving life expectancy and reducing maternal complications as well as providing reassurance to family members when a diagnosis is ruled out. This document is an expert opinion reflecting strategies put forward by medical experts and patient representatives involved in the HTAD Rare Disease Working Group of VASCERN. It aims to provide a patient pathway that improves patient care by diminishing time to diagnosis, facilitating the establishment of a correct diagnosis using molecular genetics when possible, excluding the diagnosis in unaffected persons through appropriate family screening and avoiding overuse of resources. It is being recommended that patients are referred to an expert centre for further evaluation if they meet at least one of the following criteria: (1) thoracic aortic dissection (<70 years if hypertensive; all ages if non-hypertensive), (2) thoracic aortic aneurysm (all adults with Z score >3.5 or 2.5–3.5 if non-hypertensive or hypertensive and <60 years; all children with Z score >3), (3) family history of HTAD with/without a pathogenic variant in a gene linked to HTAD, (4) ectopia lentis without other obvious explanation and (5) a systemic score of >5 in adults and >3 in children. Aortic imaging primarily relies on transthoracic echocardiography with magnetic resonance imaging or computed tomography as needed. Genetic testing should be considered in those with a high suspicion of underlying genetic aortopathy. Though panels vary among centers, for patients with thoracic aortic aneurysm or dissection or systemic features these should include genes with a definitive or strong association to HTAD. Genetic cascade screening and serial aortic imaging should be considered for family screening and follow-up. In conclusion, the implementation of these strategies should help standardise the diagnostic work-up and follow-up of patients with suspected HTAD and the screening of their relatives.     

基于CT图像胸主动脉夹层与正常胸主动脉内血流动力学模拟对比分析

目的通过对基于CT图像的血流动力学数值模拟获得的患有降主动脉夹层与正常胸主动脉内的血流动力学参数的比较,分析主动脉夹层内血液流动状态与动脉夹层疾病的关系,为阐明主动脉夹层疾病的发病机制提供理论依据。方法患者A为46岁男性,胸主动脉正常;患者B为33岁女性,患有通腔型降主动脉夹层,即通腔形式的DeBakeyⅢ型主动脉夹层。CT图像为DICOM格式,层间距为0.5mm,每片图像的平面分辨率为512×512,像素大小为0.5mm。应用医学图像后处理软件对通过临床获得的CT二维医学图像数据进行处理重构,得到正常和患有降主动脉夹层的胸主动脉三维立体模型并转化为可用于模拟计算的计算机辅助设计（CAD）模型。应用计算流体力学（CFD）软件模拟胸主动脉内血流情况,获得相关血流动力学参数。结果计算出胸主动脉在心动周期内不同时刻的血流动力学参数。结论在心动周期内患有动脉夹层胸主动脉内血流情况较正常胸主动脉内血流情况更为复杂,表现为管壁压力变化较大、夹层开口处出现多个漩涡等现象,表明主动脉夹层内复杂血流情况与主动脉夹层疾病的发病机制存在一定的关系。     

Determination of fractional flow reserve (FFR) based on scaling laws: a simulation study

Fractional flow reserve (FFR) provides an objective physiological evaluation of stenosis severity. A technique that can measure FFR using only angiographic images would be a valuable tool in the cardiac catheterization laboratory. To perform this, the diseased blood flow can be measured with a first pass distribution analysis and the theoretical normal blood flow can be estimated from the total coronary arterial volume based on scaling laws. A computer simulation of the coronary arterial network was used to gain a better understanding of how hemodynamic conditions and coronary artery disease can affect blood flow, arterial volume and FFR estimation. Changes in coronary arterial flow and volume due to coronary stenosis, aortic pressure and venous pressure were examined to evaluate the potential use of flow and volume for FFR determination. This study showed that FFR can be estimated using arterial volume and a scaling coefficient corrected for aortic pressure. However, variations in venous pressure were found to introduce some error in FFR estimation. A relative form of FFR was introduced and was found to cancel out the influence of pressure on coronary flow, arterial volume and FFR estimation. The use of coronary flow and arterial volume for FFR determination appears promising.     

Lumbar shape characterization of the neural arch and vertebral body in spondylolysis: A comparative skeletal study

The lumbar vertebral shape is an important causative factor in spondylolysis (SP). However, a complete characterization of this shape, that would shed light on its pathophysiology enhance its earlier diagnosis, is still missing. The aim of this study was to evaluate the shape distinctiveness of the lumbar (L1-L5) vertebral body (VB) and neural arch (isthmus, lamina, vertebral canal, spinous, and transverse processes) in SP. Using a three-dimensional (3D) digitizer, the VB length, width, height, and sagittal wedging as well as the lengths of the isthmus, lamina spinous, and transverse processes of all lumbar vertebrae (L1-L5) were measured from 115 male skeletons with bilateral SP at L5 and compared with 120 normal ones. Compared with the normal group, the following results were indicated in SP [analysis of variance (ANOVA), P < 0.05]: the VB's are significantly longer at the superior surfaces of L1-L4 and inferior surfaces of L1-L3 (total mean difference = 7.61 mm and 3.94 mm, respectively), and wider at the superior surfaces of L1-L4 and inferior surfaces of L1-L5 (total mean difference = 10.06 mm and 12.90 mm, respectively); The L5 VB is significantly shorter posteriorly (mean difference = 3.05 mm) and more lordotic (+1° of dorsal wedging); L5 is manifested with longer lamina (mean difference = 1.85-2.18 mm), longer isthmus (mean difference = 3.24-4.69 mm), and longer and wider vertebral canal (mean differences = 3.64 mm and 1.13 mm, respectively); The L2-L5 spinous processes are significantly longer (total mean difference = 7.45 mm). Clinically, detecting the aforementioned unique lumbar vertebral morphometric features in individuals suffering from chronic low back pain may facilitate the early diagnosis of SP.     

Variability in facial‐muscle innervation: A comparative study based on electrostimulation and anatomical dissection

Facial‐nerve palsy is the most common complication during facial surgery. However, there are few detailed reports on the distribution of the terminal branches of the facial nerve to the mimetic muscles. This also applies to the communicating branches. The aim of our study was to assess the variability of communicant and terminal branches of the facial nerve in humans. This prospective study involved anatomical dissections and intraoperative electric stimulation of facial nerves. We first performed 30 dissections to define the branching patterns of the extracranial facial nerve, with particular focus on the penetrating points into the mimetic muscles. We then studied and compared these preliminary data with 14 operative facial stimulations conducted during parotidectomies. Each trunk and branch received systematic electrostimulation. The electrostimulation and facial‐and‐neck movements were analyzed by two independent reviewers. The peripheral branching and intercommunication of the facial branches were highly variable. Combining electrostimulation and dissections, the frontalis muscle, the depressor labii inferioris and the platysma showed little nerve recuperation whereas the sphincter muscles (orbicularis ori and oculi) were anatomically protected. Facial‐muscle innervation differed among individuals. We found complex variations in the facial branching mode. Our study highlights the branches and corresponding areas that could be considered anatomically risky. Clin. Anat. 32:169–175, 2019. © 2018 Wiley Periodicals, Inc.     

Influence of pulse pressure variation on the results of local arterial compliance measurement: A computer simulation study

A computer simulation has been performed to study the influence of the pulse pressure variation on the arterial compliance readings in regard to different calculation techniques and arterial wall elastic properties. We applied the derivative- and amplitude-based (delta-based) calculation techniques to the model of the pressure vs. arterial lumen area relationship of different arteries. The simulated pulse pressure increase resulted in an essential reduction of the delta-based compliance in its near maximum region, and in an increase or no change outside this region. In the case of the relationship of a lower steepness the alterations were smaller.     

Infantile digital fibromatosis-like tumour (inclusion body fibromatosis) of adulthood: report of two cases with ultrastructural and immunocytochemical findings

Two adult cases of a cutaneous lesion indistinguishable from typical infantile digital fibromatosis are added to the unique similar case so far reported in adulthood. The immunocytochemical localization of vimentin and muscle actin in the proliferating cells confirms their myofibroblastic nature and establishes closer relationships between the adult and the infantile variants of this entity. These two variants, however, appear to be clinically different, since all the adult cases were extradigital and did not recur after surgical excision. The term inclusion body fibromatosis underlines the histological hallmark of the lesion and should be used to identify this entity in place of recurrent infantile digital fibromatosis which does not seem any longer appropriate.     

Morphometric analysis of the relationships between intervertebral disc and vertebral body heights: an anatomical and radiographic study of the human thoracic spine

The main aim of this study was to provide anatomical data on the heights of the human intervertebral discs for all levels of the thoracic spine by direct and radiographic measurements. Additionally, the heights of the neighboring vertebral bodies were measured, and the prediction of the disc heights based only on the size of the vertebral bodies was investigated. The anterior (ADH), middle (MDH) and posterior heights (PDH) of the discs were measured directly and on radiographs of 72 spine segments from 30 donors (age 57.43 ± 11.27 years). The radiographic measurement error and the reliability of the measurements were calculated. Linear and non-linear regression analyses were employed for investigation of statistical correlations between the heights of the thoracic disc and vertebrae. Radiographic measurements displayed lower repeatability and were shorter than the anatomical ones (approximately 9% for ADH and 37% for PDH). The thickness of the discs varied from 4.5 to 7.2 mm, with the MDH approximately 22.7% greater. The disc heights showed good correlations with the vertebral body heights (R(2), 0.659-0.835, P-values < 0.005; anova), allowing the generation of 10 prediction equations. New data on thoracic disc morphometry were provided in this study. The generated set of regression equations could be used to predict thoracic disc heights from radiographic measurement of the vertebral body height posterior. For the creation of parameterized models of the human thoracic discs, the use of the prediction equations could eliminate the need for direct measurement on intervertebral discs. Moreover, the error produced by radiographic measurements could be reduced at least for the PDH.     

Ethnic differences in body composition and the associated metabolic profile: A comparative study between Asians and Caucasians

It is estimated that Asia will be the home of more than 100 million people with type 2 diabetes by the year of 2025. This region combines a high proportion of the world's population with rapidly rising diabetes prevalence rates. The increase in diabetes in Asia differs from that reported in other parts of the world: it has developed in a shorter time, in a younger age group, and in people with lower body-mass index (BMI).     

Glaucoma-lens ectopia-microspherophakia-stiffness-shortness (GEMSS) syndrome: A dominant disease with manifestations of Weill-Marchesani syndromes

We report on a syndrome of progressive joint stiffness, glaucoma, and lens dislocation observed in three generations and compare it with two previous records of short stature, lens ectopia, and articular limitation. This family confirms the existence of a dominant Weill-Marchesani-like syndrome. We suggest that it could be related to the Moore-Federman syndrome. We coin the acronym GEMSS syndrome (Glaucoma, Ectopia, Microspher-ophakia, Stiff joints, Short stature) to distinguish this dominant Weill-Marchesani-like syndrome from the classic, recessively inherited syndrome. © 1992 Wiley-Liss, Inc.     

Monitoring muscle over three orders of magnitude: Widespread positive allometry among locomotor and body support musculature in the pectoral girdle of varanid lizards (Varanidae)

There is a functional trade-off in the design of skeletal muscle. Muscle strength depends on the number of muscle fibers in parallel, while shortening velocity and operational distance depend on fascicle length, leading to a trade-off between the maximum force a muscle can produce and its ability to change length and contract rapidly. This trade-off becomes even more pronounced as animals increase in size because muscle strength scales with area (length²) while body mass scales with volume (length³). In order to understand this muscle trade-off and how animals deal with the biomechanical consequences of size, we investigated muscle properties in the pectoral girdle of varanid lizards. Varanids are an ideal group to study the scaling of muscle properties because they retain similar body proportions and posture across five orders of magnitude in body mass and are highly active, terrestrially adapted reptiles. We measured muscle mass, physiological cross-sectional area, fascicle length, proximal and distal tendon lengths, and proximal and distal moment arms for 27 pectoral girdle muscles in 13 individuals across 8 species ranging from 64 g to 40 kg. Standard and phylogenetically informed reduced major axis regression was used to investigate how muscle architecture properties scale with body size. Allometric growth was widespread for muscle mass (scaling exponent >1), physiological cross-sectional area (scaling exponent >0.66), but not tendon length (scaling exponent >0.33). Positive allometry for muscle mass was universal among muscles responsible for translating the trunk forward and flexing the elbow, and nearly universal among humeral protractors and wrist flexors. Positive allometry for PCSA was also common among trunk translators and humeral protractors, though less so than muscle mass. Positive scaling for fascicle length was not widespread, but common among humeral protractors. A higher proportion of pectoral girdle muscles scaled with positive allometry than our previous work showed for the pelvic girdle, suggesting that the center of mass may move cranially with body size in varanids, or that the pectoral girdle may assume a more dominant role in locomotion in larger species. Scaling exponents for physiological cross-sectional area among muscles primarily associated with propulsion or with a dual role were generally higher than those associated primarily with support against gravity, suggesting that locomotor demands have at least an equal influence on muscle architecture as body support. Overall, these results suggest that larger varanids compensate for the increased biomechanical demands of locomotion and body support at higher body sizes by developing larger pectoral muscles with higher physiological cross-sectional areas. The isometric scaling rates for fascicle length among locomotion-oriented pectoral girdle muscles suggest that larger varanids may be forced to use shorter stride lengths, but this problem may be circumvented by increases in limb excursion afforded by the sliding coracosternal joint.     

The European Registry on Obstetric Antiphospholipid Syndrome (EUROAPS): A survey of 1000 consecutive cases

Aim

To analyse the clinical features, laboratory data and foetal-maternal outcomes, and follow them up on a cohort of 1000 women with obstetric antiphospholipid syndrome (OAPS).

Safety and preliminary efficacy on cognitive performance and adaptive functionality of epigallocatechin gallate (EGCG) in children with Down syndrome. A randomized phase Ib clinical trial (PERSEUS study)

PurposeAlthough some caregivers are using epigallocatechin gallate (EGCG) off label in hopes of improving cognition in young adults with Down syndrome (DS), nothing is known about its safety, tolerability, and efficacy in the DS pediatric population. We aimed to evaluate safety and tolerability of a dietary supplement containing EGCG and if EGCG improves cognitive and functional performance.MethodsA total of 73 children with DS (aged 6-12 years) were randomized. Participants received 0.5% EGCG (10 mg/kg daily dose) or placebo for 6 months with 3 months follow up after treatment discontinuation.ResultsIn total, 72 children were treated and 66 completed the study. A total of 38 participants were included in the EGCG group and 35 in the placebo group. Of 72 treated participants, 62 (86%) had 229 treatment-emergent adverse events (AEs). Of 37 participants in the EGCG group, 13 (35%) had 18 drug-related treatment-emergent AEs and 12 of 35 (34%) from the placebo group had 22 events. In the EGCG group, neither severe AEs nor increase in the incidence of AEs related to safety biomarkers were observed. Cognition and functionality were not improved compared with placebo. Secondary efficacy outcomes in girls point to a need for future work.ConclusionThe use of EGCG is safe and well-tolerated in children with DS, but efficacy results do not support its use in this population.