Arthrogryposis multiplex congenita: An autopsy case of a fatal form

A case of a severe and fatal form of arthrogryposis multiplex congenita with a full necropsy examination is presented in which the central nervous system and many muscles of the four extremities were examined histologically. The most striking feature was a great reduction in the muscular tissue of the limbs with a marked increase in the adipose tissue. The muscular changes were thought to be caused by neurogenic atrophy, and microscopy of the spinal cord revealed developmental abnormalities, including degenerative changes of the anterior horn cells. Neonatal and fatal cases of arthrogryposis multiplex congenita reported in the literature are briefly reviewed, and the characteristics of the present case and its relation to other congenital neuromuscular disorders are discussed.     

Involvement of the larynx in a congenital “myopathy”, unilateral aplasia of the arytenoid,micrognathia, and malformation of the brain — A new syndrome?

Summary Neuromyopathic changes were found in various limb muscles and in intrinsic laryngeal muscles of a two month old girl. She had been noted to have micrognathia, arthrogryposis and congenital stridor and died as a result of respiratory insufficiency and aspiration. Autopsy revealed an absent left arytenoid cartilage and severe histogenic abnormalities of the brain. Although the muscles involved showed a mainly myopathic pattern, marked signs of peripheral neurogenic involvement were present. These differed from motor neurone disease or aplasia of anterior horn cells. These findings cast a new light on the discussion of unclassified congenital myopathy resembling the picture of congenital muscular dystrophy. This is the first case of congenital neuromyopathy in which involvement of intrinsic laryngeal muscles has been demonstrated morphologically.     

Misoprostol embryotoxicity: clinical evaluation of fifteen patients with arthrogryposis

We report on clinical evaluations of Brazilian patients with misoprostol-induced arthrogryposis. All 15 patients had growth retardation, underdeveloped bones, short feet with equinovarus, rigidity of several joints with skin dimples and webs, decreased movement of legs stemming from neurologic impairment, bilateral symmetrical hypoplasia or atrophy of limb muscles, and absent tendon reflexes. Of the 15 patients, five had upper limb deformities in addition to lower limb involvement, and one had spinal cord disruption leading secondarily to segmental sensory loss and neurogenic bladder and bowel. Electroneuromyography of five patients indicated that the abnormalities were of neurogenic origin and suggestive of anterior horn cell defects. All of their mothers took 400-4,800 mcg of misoprostol orally or vaginally at 8 to 12 weeks of pregnancy. Our observations support a previously stated caution with regard to the embryotoxicity of misoprostol.     

Freeman-Sheldon syndrome: a disorder of congenital myopathic origin?

Freeman-Sheldon syndrome was diagnosed in an unrelated adult man and woman, with severe abnormalities of the extremities but only slight anomalies of the face. Electromyography and muscle biopsy showed a myopathy which was classified as a congenital disproportion of fibre type and seemed to be the primary cause of the deformities. This allowed classification of the syndrome as a separate type of myopathic arthrogryposis.     

牛脊髓前角匀浆皮下注射损伤豚鼠脊髓运动神经元

目的探讨牛脊髓前角匀浆对豚鼠脊髓、前根及坐骨神经的影响。方法采用新鲜牛脊髓前角匀浆免疫豚鼠。观察脊髓、前根、坐骨神经光镜及超微结构的变化。结果豚鼠体重在第4次免疫后明显下降。脊髓前角运动神经元变性和丢失,有卫星、噬节及墓穴现象形成。电镜下最主要的表现是线粒体异常;其次神经元核周质内异常神经丝聚集,形成包涵体;轴突内异常神经丝聚集形成轴索球。前根及坐骨神经的变化,表现为轴索变性及继发的髓鞘改变。结论牛脊髓前角匀浆可以作为抗原引起豚鼠脊髓、前根及坐骨神经免疫所介导的损伤,为进一步研究运动神经元病的发病机制提供了可靠的方法。     

免疫介导运动神经元损伤豚鼠模型的建立

目的建立免疫介导运动神经元损伤动物模型。方法取成年雄性白化病远交系Hartley豚鼠,用新鲜牛脊髓前角匀浆、弗氏佐剂和PBS制成油包水乳剂,于豚鼠背部皮下/皮内接种。观察动物的行为学表现及肌电图改变。取材进行组织学和血清抗豚鼠脊髓前角抗体检查。结果牛脊髓前角匀浆免疫后,豚鼠17/19只出现肢体和/或颈部肌肉无力、肌肉萎缩;肌电图示失神经改变及运动单位电位波幅增高、时限增长;运动皮质大锥体细胞及大脑脚有髓神经纤维均有不同程度的改变;脊髓颈腰膨大前角运动神经元变性、丢失及胶质细胞增生。免疫组豚鼠血清内抗豚鼠脊髓前角抗体滴度升高,脊髓前角运动神经内可见IgG沉积。结论本实验成功建立了免疫介导的运动神经元损伤动物模型。     

Congenital muscular dystrophy associated with lethal arthrogryposis multiplex congenita

Summary Two unrelated patients with severe arthrogryposis multiplex congenita (AMC) who died perinatally, are presented. In both, postmortem examination revealed an intact nervous system and striking dystrophic muscle changes, consistent with congenital muscular dystrophy (CMD). Few similar cases have been reported before, but since the condition is not well known, it seems probable that in the past many have been labeled as mere multiple malformations. The possibility of an underlying muscular disorder, either primary myopathic or neurogenic should be considered in any patient with early lethal AMC. Our findings confirm that the fetal akinesia-arthrogryposis sequence is a nonspecific clinical syndrome resulting from various causes of muscular inactivity in utero. The main objective of this report is to provide reasonable guidelines on how to approach the problem of classification. We favor a pathogenetic approach, depending upon careful sampling of the central nervous system and skeletal muscles at autopsy.     

A Neurogenic Component in Muscular Dystrophy

Evidence for a neurogenic component in mouse and human muscular dystrophy is briefly reviewed. Such evidence comes from certain clinical observations, electrophysiological studies, muscle pathology, nervous system pathology, transplantation experiments in animals, and tissue culture studies. The evidence is at present rather conflicting though the results of recent tissue culture experiments are more convincing. If there is a neurogenic component in dystrophy then the basic defect may have to be sought in the central nervous system rather than in the muscle itself. It is argued, however, that a neurogenic component in dystrophy cannot be simply a defect in the anterior horn cells of the spinal cord since the clinical features and the laboratory and pathological findings are quite different from those in spinal muscular atrophy.     

Oculopharyngeal muscular dystrophy. Description of a case with involvement of the central nervous system

A sporadic case of oculopharyngeal muscular dystrophy occurred in a 74-year-old woman is described. High levels of IgA and IgG in the serum, and esophageal smooth muscle involvement are shown. Electromyography of several limb muscles displayed myopathic pattern with giant polyphasic motor unit potentials, suggesting superimposed denervation. The histological examination of peroneus brevis muscle biopsy specimen showed myopathic changes with dystrophic features, associated with neurogenic changes, including atrophic angulated fibers, small-group atrophy and type-grouping: concomitant involvement of spinal motor neuron pathway is hypotized, normal values of motor and sensory nerve conduction velocities excluding associated polineuropathy. Furthermore, Somatosensory Evoked Potentials recording revealed bilaterally increased Central Conduction Time. Referring to other similar cases previously reported in the literature, the significance of neurogenic involvement in oculopharyngeal muscular dystrophy is discussed.     

复方丹参对脊髓损伤大鼠一氧化氮合酶神经元的影响

目的：探讨丹参治疗脊髓损伤的机制。方法：大鼠按Allen‘s法制备脊髓损伤动物模型。用复方丹参注射液腹腔注射治疗;用NADPH-d组化方法测定NOS神经元变化,并做图像分析。结果：脊髓损伤大鼠用复方丹参注射液治疗后,脊髓前角内的NOS阳性细胞增多,表达升高;而后角内几乎未见阳性细胞。结论：脊髓损伤大鼠经过复方丹参注射液治疗后,脊髓前角内NO的合成增加,但后角内NO合成下降。     

异种脊髓前角匀浆对豚鼠前角运动神经元的影响

目的：观察豚鼠脊髓前角运动神经元在异种脊髓前角匀浆免疫后的变化。方法：猪脊髓前角匀浆免疫豚鼠后,豚鼠脊髓前角以苏木精-伊红、甲苯胺蓝及IgG免疫组化染色,同时电镜下观察前角运动神经元的超微变化。结果：豚鼠脊髓前角运动神经元存在变性和丢失,以神经元固缩、胶质细胞围绕破坏的神经元形成卫星现象及小墓穴为主,脊髓前角运动神经元胞质内IgG沉积呈颗粒状分布。运动神经元胞质内内质网扩张、线粒体肿胀。结论：猪脊髓前角匀浆作为抗原可引起豚鼠下运动神经元损伤,说明猪与豚鼠运动神经元存在共同抗原,自身免疫机制可能参与了运动神经元变性过程。     

A gene for a severe lethal form of X-linked arthrogryposis (X-linked infantile spinal muscular atrophy) maps to human chromosome Xp11.3-q11.2

X-linked arthrogryposis Type I (X-linked infantile spinal muscularatrophy) is a rare disorder showing hypotonia, areflexia, andmultiple congenital contractures (arthrogryposis) associatedwith loss of anterior horn cells and death in infancy. We havestudied an X-linked arthrogryposis family using highly polymorphicmlcrosateiiite markers throughout the X chromosome. Meioticbreakpoint analysis (concordance analysis) based on shared regionsof the founder X chromosome was successful in localizing theX-linked arthrogryposis gene to Xp11.3–q11.2. in thisregion, the highest two-point lod score was found with DXS991(Z_max=2.63,     

The response of ventral horn neurons to ricin. An experimental abiotrophy model

The morphological alterations of anterior horn neurons of the spinal cord of rabbits produced by the administration of ricin conveyed via retrograde axonal flow are described. The differences with the primary response after axonal transection and the similarity with degenerative abiotrophic systemic lesions are discussed.     

增殖性细胞核抗原和c-Fos蛋白参与调控人胚胎脊髓的发育

Objective To explore effects of proliferating cell nuclear antigen (PCNA)and c-Fos protein on the early and middle embryonic development of the human spinal cord. Methods Using immunohistochemical method, the expression of PCNA and c-Fos were investigated in the central canal, anterior horn and posterior horn of spinal cord of 16 human embryos aged at the second to fourth month of gestation. Results At the second month of gestation, there were the positive PCNA immunohistochemical reaction in the central canal and alar plate of the spinal cord, but not in the basal plate. The c-Fos immunohistochemical positive reaction were localized in the epithelial cells of the central canal, alar plate and basal plate of the spinal cord. Following growth, the positive immunohistochemical staining for PCNA was also found in the epithelial cells of the central canal, anterior horn, and posterior horn of the spinal cord. The average intensity and cell number of the c-Fos immunohistochemical positive profiles decreased first, and then increased in spinal cord anterior horn (EM>P /EM><0.01), but no changes was found in the posterior horn of the spinal cord. Conclusion PCNA and c-Fos proteins may regulate the growth and development of the neuroepithelial cells of the neural tube of the human embryo.     

Lethal congenital contracture syndrome (LCCS) and other lethal arthrogryposes in Finland--an epidemiological study

Arthrogryposis multiplex congenita is a heterogeneous group of disorders characterized by multiple contractures with an estimated frequency of 1 in 3,000 births. With improving diagnostic methods, increasing numbers of fetuses with arthrogryposis are found. The pathogenetic mechanisms are relatively well known but the epidemiology and genetics of the prenatally lethal forms of arthrogryposis are less well known. In this study we collected all cases of a multiple contractures diagnosed in Finland during 1987-2002 including live born infants, stillbirths, and terminated pregnancies. Ninety-two cases of 214 suffered intrauterine demise (68 selective pregnancy terminations and 24 stillbirths) and 58 died in infancy. In 141 out of these cases the diagnosis could be included within lethal arthrogryposes, with a prevalence of 1 in 6,985 (1.43/10,000) births. Of these, 59 had spinal cord pathology at autopsy and thus were of neurogenic origin. Thirty-nine cases had lethal congenital contracture syndrome (LCCS) clinically characterized by total immobility of the fetus at all ultrasound examinations (12 weeks or later), multiple joint contractures in both upper and lower limbs, hydrops, and fetal death before the 32nd week of pregnancy. LCCS is noted as a unique Finnish disorder with a prevalence of 1 in 25,250 (0.40/10,000) births and is a major cause of lethal arthrogryposis in Finland.     

Segmental motor and sensory innervation of muscles in anterior leg compartment as revealed by retrograde transport of horseradish peroxidase

Horseradish peroxidase (HRP) tracing technique was used to label and localize motor and sensory neurons innervating tibialis anterior, extensor hallucis longus and extensor digitorum longus muscles of the anterior leg compartment of the rat. The tibialis anterior sensory neurons were located in the ipsilateral L4 and L5 spinal ganglia. Cells of origin of tibialis anterior motor endings were also found in the ipsilateral ventral horn of the same cord segments as the labeled sensory ganglia. Extensor hallucis longus sensory neurons were located in L4 to L6 spinal ganglia, while its labeled motor neurons were located in L4 and L5 spinal cord segments. The motor neurons innervating the extensor digitorum longus muscle were located in L4 to L6 spinal cord segments; its sensory neurons were previously localized. All labeled motor and sensory neurons were present on the ipsilateral side. Almost all motoneurons innervating the 3 muscles were present in the dorsolateral nucleus of the ventral horn.     

Abnormal astrocyte differentiation and defective cellular interactions in wobbler mouse spinal cord

Summary The wobbler mutation is inherited as an autosomal recessive trait and displays a muscular atrophy associated with motoneuron degeneration in early postnatal development. It has been shown that the level of glial fibrillary acidic protein (GFAP) is greatly increased in the spinal cord of wobbler mice. We performed immunocytochemical analyses combined with confocal microscopy to study the developmental distribution of GFAP-positive astrocytes in the spinal cord of wobbler mice during the course of the disease, and in primary cultures of adult wobbler spinal cord astrocytes. Many changes in the number and distribution of astrocytes were observed in the wobbler mice from 1–10 months post-partum. Strongly GFAP-positive astrocytes are present in small number in the anterior horn by 1 month. They increase in number and are observed in the entire spinal cord grey and white matters by 2–10 months. These reactive astrocytes have thick, short, extensively branched processes which contrast with the long, unbranched processes observed in control mice. The wobbler astrocyte processes are oriented perpendicular to the surface of the spinal cord, which contrasts with the normal parallel, concentric orientation. No expansion of astrocyte processes exit from the white matter towards the grey matter. Moreover, the surface of the wobbler spinal cord beneath the meninges displays a dramatic decrease of interdigitating processes, end feet and flattened cell bodies of astrocytes that form a disorganized layer.In vitro, mutant astrocytes have morphological characteristics similar to thosein vivo and, in particular, develop short, thick, branched processes. These mutant astrocytes in cultures do not contact one another, whereas normal mature cultures show an increased incidence of cell-cell contacts between long processes. The increase of astrocyte reactivity associated with these modifications in astrocytic process arrangement may reflect an important primary event in the course of the wobbler disease rather than a non-specific response to motoneuronal death.     

A recessive form of congenital contractures and torticollis associated with malignant hyperthermia.

Two families are presented, each with two affected sibs, all four of whom seem to have a newly described and specific form of congenital contractures (arthrogryposis). The affected subjects have congenital torticollis, dysmorphic, asymmetrical, myopathic facial features, and progressive scoliosis. Two sibs had cleft palate. Malignant hyperthermia has occurred in two of the patients.