Historical Perspective of Split Cord Malformations: A Tale of Two Cords.

INTRODUCTION: Our appreciation and understanding of what is now known as the split cord malformation (SCM) have a long history. The oldest known example of SCM is from roughly AD 100. Other isolated examples can be found in the large body of work of the pathologists of the 1800s, where the SCMs were found incidentally during autopsies. CONCLUSIONS: SCM has a rich history and has intrigued physicians for over 200 years. Many well-known figures from the past such as Chiari and von Recklinghausen, both pathologists, made early postmortem descriptions of SCM. With the advent of MRI, these pathological embryological derailments can now often be detected and appreciated early and during life. Our understanding and ability to treat these congenital malformations as well as the terminology used to describe them have changed over the last several decades.

History of the current understanding and management of tethered spinal cord.

An understanding of the underlying pathophysiology of tethered cord syndrome (TCS) and modern management strategies have only developed within the past few decades. Current understanding of this entity first began with the understanding and management of spina bifida; this later led to the gradual recognition of spina bifida occulta and the symptoms associated with tethering of the filum terminale. In the 17th century, Dutch anatomists provided the first descriptions and initiated surgical management efforts for spina bifida. In the 19th century, the term "spina bifida occulta" was coined and various presentations of spinal dysraphism were appreciated. The association of urinary, cutaneous, and skeletal abnormalities with spinal dysraphism was recognized in the 20th century. Early in the 20th century, some physicians began to suspect that traction on the conus medullaris caused myelodysplasia-related symptoms and that prophylactic surgical management could prevent the occurrence of clinical manifestations. It was not, however, until later in the 20th century that the term "tethered spinal cord" and the modern management of TCS were introduced. This gradual advancement in understanding at a time before the development of modern imaging modalities illustrates how, over the centuries, anatomists, pathologists, neurologists, and surgeons used clinical examination, a high level of suspicion, and interest in the subtle and overt clinical appearances of spinal dysraphism and TCS to advance understanding of pathophysiology, clinical appearance, and treatment of this entity. With the availability of modern imaging, spinal dysraphism can now be diagnosed and treated as early as the intrauterine stage.

[Neural tube defects and folic acid: a historical overview of a highly successful preventive intervention]. / Defectos del tubo neural y del ácido fólico: recorrido histórico de una intervención preventiva altamente efectiva.

This article gives a broad overview of part of the historical evolution of medical knowledge about neural tube defects (NTD) and the discovery of vitamin B9 or folic acid, as well as some relevant research events that, over the course of several centuries, defined the relationships between the understanding of central nervous system embryology, the discovery of the vitamin, the correlation between folic acid and cell proliferation and lastly the development of preventive measures for this type of defects. This narrative allows us to examine historically relevant concepts underlying clinical actions with a populational impact that prevent NTDs via folic acid consumption prior to conception.

Homocysteine: a history in progress.

This paper shows that the linkage between basic science and clinical research has characterized the field of sulfur amino acid metabolism since 1810, when Wollaston isolated cystine from a human bladder stone. The nature and consequences of this relationship are discussed.

Chiari's description of cerebellar ectopy (1891). With a summary of Cleland's and Arnold's contributions and some early observations on neural-tube defects.

One hundred years ago, Chiari published his first paper on cerebellar ectopy. The contribution of his paper and those of Cleland (1883) and Arnold (1894) to the development of the knowledge of craniocervical abnormalities is discussed. Some early contributions (those of Tulp and Ollivier d'Angers) to the subject of neural-tube defects were also studied and it is concluded that Chiari's name should be connected with the different types of cerebellar ectopy.

Triple osteotomy of the innominate bone. 1973.

In forty-five patients, twenty-three with congenital dislocations and the rest with paralytic or other disturbances, this new displacement osteotomy of the hip joint was done when other iliac osteotomies were considered ineffective. The patients, seven to seventeen years old, were followed two to ten years. Of the fifty-two procedures, forty were satisfactory. Most of the unsatisfactory results were in cases of myelodysplasia, peroneal atrophy, and cerebral palsy.

Homocysteine and human reproduction.

Homocysteine is an amino acid that is capable of disturbing the proper growth of cells. Hyperhomocysteinemia can lead to a non-closure of the neural tube. The underlying basis is a derangement of homocysteine metabolism due to a missense mutation of the MTHFR enzyme that has to catalyze the folate metabolic cycle furnishing sufficient methyl groups for DNA and tRNA synthesis. Folate can overcome the dysfunction of the mutation and the decreased activity of the thermolabile MTHFR. Homocysteine is also recognized as an independent risk factor for obstetrical vascular disease that can manifest itself in maternal veins (thrombosis), arteries (preeclampsia) or spiral arteries supplying the placenta (placental abruption). Low vitamin status (folic acid, vitamin B6 and B12), hyperhomocysteinemia, the MTHFR gene mutation C677T, and thrombotic factors like Protein C, Protein S. antithrombin III, factor V Leiden and Activated Protein C, are alone or in combination high risk factors for obstetrical vascular disease. Their values can be modulated by B-vitamin status and could be able to prevent disease from occurring or recurring. Placebo-randomized trials have been done in neural tube defects but are urgently needed in the vascular area. The common denominator of the effect of homocysteine on the embryo and the blood vessels (endothelium) could be sited in the process of proliferation of cells that need proper methyl groups for proper function.

Making birth defects 'preventable': pre-conceptional vitamin supplements and the politics of risk reduction.

Since the mid-1990s, governments and health organizations around the world have adopted policies designed to increase women's intake of the B-vitamin 'folic acid' before and during the first weeks of pregnancy. Building on initial clinical research in the United Kingdom, folic acid supplementation has been shown to lower the incidence of neural tube defects (NTDs). Recent debate has focused principally on the need for mandatory fortification of grain products with this vitamin. This article takes a longer view, tracing the transformation of folic acid from a routine prenatal supplement to reduce the risk of anaemia to a routine 'pre-conceptional' supplement to 'prevent' birth defects. Understood in the 1950s in relation to social problems of poverty and malnutrition, NTDs were by the end of the century more likely to be attributed to individual failings. This transition was closely associated with a second. Folic acid supplements were initially prescribed to 'high-risk' women who had previously borne a child with a NTD. By the mid-1990s, they were recommended for all women of childbearing age. The acceptance of folic acid as a 'risk-reducing drug' both relied upon and helped to advance the development of preventive and clinical practices concerned with women's health before pregnancy.

Apparent prevention of neural tube defects by periconceptional vitamin supplementation. 1981.

An earlier preliminary paper is expanded. Women who had given birth to one or more infants with a neural tube defect were recruited into a trial of periconceptional vitamin supplementation. Two hundred mothers attending five centres were fully supplemented (FS), 50 were partially supplemented (PS), and 300 were unsupplemented (US). Neural tube defect recurrences in the study pregnancies were 1(0.5%), in FS, none in PS, and 13 (4%) in US mothers. The difference in outcome between FS and US mothers is significant. The most likely explanation is that supplementation has prevented some neural tube defects, but further studies are needed.

Folic acid food fortification-its history, effect, concerns, and future directions.

Periconceptional intake of folic acid is known to reduce a woman's risk of having an infant affected by a neural tube birth defect (NTD). National programs to mandate fortification of food with folic acid have reduced the prevalence of NTDs worldwide. Uncertainty surrounding possible unintended consequences has led to concerns about higher folic acid intake and food fortification programs. This uncertainty emphasizes the need to continually monitor fortification programs for accurate measures of their effect and the ability to address concerns as they arise. This review highlights the history, effect, concerns, and future directions of folic acid food fortification programs.

Cats, frogs, and snakes: early concepts of neural tube defects.

Disturbed neurulation fascinated scientists of all times. In Egypt, anencephalic infants were venerated as animal-headed gods. Roman law required them to be killed. The medieval world held the mother responsible, either because of assumed imagination or "miswatching," or because of suspected intercourse with animals or devils. Modern embryology and teratology began with the use of the microscope by Malpighi in 1672. Details of neural tube closure were described by Koelliker in 1861 and by His in 1874. From 1822, genetic disease and familial recurrence due to insufficient nutrition were discerned and lower social class identified as a risk factor. It took a century to define the malnutrition as insufficient folate intake. The mandatory supplementation of folate in staple foods successfully reduced the incidence of neural tube defects in the United States, Australia, Canada, and Chile, but it was not adopted by most European countries.

Defectos del tubo neural y del ácido fólico: recorrido histórico de una intervención preventiva altamente efectiva / Neural tube defects and folic acid: a historical overview of a highly successful preventive intervention

Este artículo describe de forma comprehensiva parte del devenir histórico que han tenido, el conocimiento médico de los defectos del tubo neural (DTN) y el descubrimiento de la vitamina B9 o ácido fólico, así como algunos de los acontecimientos investigativos relevantes que a través de varios siglos definieron las relaciones entre la comprensión de la embriología del sistema nervioso central, el descubrimiento de la vitamina, la correlación del ácido fólico con la proliferación celular y finalmente el desarrollo de medidas preventivas de este tipo de defectos. Se pretende, a través de esta narrativa, exponer los conceptos históricamente relevantes que sustentan las acciones de índole clínico y de impacto poblacional que previenen los DTN a través del consumo preconcepcional de ácido fólico.

This article gives a broad overview of part of the historical evolution of medical knowledge about neural tube defects (NTD) and the discovery of vitamin B9 or folic acid, as well as some relevant research events that, over the course of several centuries, defined the relationships between the understanding of central nervous system embryology, the discovery of the vitamin, the correlation between folic acid and cell proliferation and lastly the development of preventive measures for this type of defects. This narrative allows us to examine historically relevant concepts underlying clinical actions with a populational impact that prevent NTDs via folic acid consumption prior to conception.

Neural tube defect in a 4000-year-old Egyptian infant mummy: a case of meningocele from the museum of anthropology and ethnography of Turin (Italy).

This paper reports a paleopathological study of a severe neural tube defect in an ancient mummy, more specifically, a meningocele in an Egyptian infant from the XI dynasty (2100-1955B.C.). This is one of the most ancient cases of meningocele in mummified human remains described in paleopathological literature. Prehistoric and early historic examples of severe congenital defects of the vertebral column and neural tube are rare, because of the precarious preservation conditions of ancient human remains. Further, since the majority are only the skeletal remains, paleopathological and paleoepidemiological analysis based on the observation of bones is even more difficult. Hence, it is not easy to investigate this disease in the past in all its complexities and true diffusion. The case presented here is peculiar, since it concerns a mummy with almost all soft tissues preserved, thus allowing us to describe the defect in an infant. Only targeted, minimally invasive examinations were performed. An anthropological investigation with helical CT scan and histological analysis was used to diagnose the defect and identify post-mortem transformation processes. The analyses confirmed the diagnosis of meningocele in an approximately six-month-old infant.