The lateral meningocele syndrome is a very rare skeletal disorder with facial anomalies, hypotonia and meningocele-related neurologic dysfunction.

This syndrome appears to be inherited in an autosomal dominant fashion.

Molecular analyses suggest that the causative mutations cause a truncation of the protein. These mutations result in the loss of PEST sequence in the protein. This loss is associated with a prolonged half life of the protein.

Mutations in Notch 3 were found to be associated with this syndrome.

Three main support groups of this syndrome are the ASGA in Australia, The Association for Children with Genetic Disorders in Poland, and the Association of People of Genetic Disorders in Greece.

Some individuals have preaxial polydactyly in the feet (unilateral in one, bilateral in 13), consisting of a small extra biphalangeal toe, in most cases with an associated rudimentary extra metatarsal, lying in a soft tissue web between the hallux and second toe. In some cases, this was accompanied by hypoplasia of the head of the first metatarsal and absence of both phalanges of the hallux.

The disorder is an autosomal dominant genetic trait caused by a mutation in the HLXB9 homeobox gene. In 2000 the first large series of Currarino cases was genetically screened for HLXB9 mutations, and it was shown that the gene is specifically causative for the syndrome, but not for other forms of sacral agenesis. The study was published on the American Journal of Human Genetics.

An initial clinical report of this syndrome describes a 6-month-old boy with rhizomelic shortening, particularly in the arms, and protuberances over the lateral aspects of the clavicles. On radiographs the lateral third of the clavicles had a appearance resulting from an abnormal process or protuberance arising from the fusion center. His 22-year-old mother also had a height of 142 cm with an arm span of 136 cm and rhizomelic shortness of the limbs, maximal in the arms, and abnormalities of the acromioclavicular joints. Both the mother and the son had marked bilateral clinodactyly of the fifth fingers associated with hypoplastic middle phalanx.

Wallis–Zieff–Goldblatt syndrome is a rare condition characterized by inherited skeletal disorders manifested mainly as short stature and lateral clavicular defects. It is also known as Cleidorhizomelic syndrome.

The Currarino syndrome (also Currarino triad) is an inherited congenital disorder where either the sacrum (the fused vertebrae forming the back of the pelvis) is not formed properly, or there is a mass in the presacral space in front of the sacrum, and (3) there are malformations of the anus or rectum. It can also cause an anterior meningocele or a presacral teratoma.

Presacral teratoma usually is considered to be a variant of sacrococcygeal teratoma. However, the presacral teratoma that is characteristic of the Currarino syndrome may be a distinct kind.

Because the cause of facial clefts still is unclear, it is difficult to say what may prevent children being born with facial clefts. It seems that folic acid contributes to lowering the risk of a child being born with a facial cleft.

Fetal trimethadione syndrome (also known as paramethadione syndrome, German syndrome, tridione syndrome, among others) is a set of birth defects caused by the administration of the anticonvulsants trimethadione (also known as Tridione) or paramethadione to epileptic mothers during pregnancy.

Fetal trimethadione syndrome is classified as a rare disease by the National Institute of Health's Office of Rare Diseases, meaning it affects less than 200,000 individuals in the United States.

The fetal loss rate while using trimethadione has been reported to be as high as 87%.

Fetal trimethadione syndrome is characterized by the following major symptoms as a result of the teratogenic characteristics of trimethadione.

- Cranial and facial abnormalities which include; microcephaly, midfacial flattening, V-shaped eyebrows and a short nose

- Cardiovascular abnormalities

- Absent kidney and ureter

- Meningocele, a birth defect of the spine

- Omphalocele, a birth defect where portions of the abdominal contents project into the umbilical cord

- A in mental and physical development

A deficiency of folate itself does not cause neural tube defects. The association seen between reduced neural tube defects and folic acid supplementation is due to a gene-environment interaction such as vulnerability caused by the C677T Methylenetetrahydrofolate reductase (MTHFR) variant. Supplementing folic acid during pregnancy reduces the prevalence of NTDs by not exposing this otherwise sub-clinical mutation to aggravating conditions. Other potential causes can include folate antimetabolites (such as methotrexate), mycotoxins in contaminated corn meal, arsenic, hyperthermia in early development, and radiation. Maternal obesity has also been found to be a risk factor for NTDs. Studies have shown that both maternal cigarette smoking and maternal exposure to secondhand smoke increased the risk for neural tube defects in offspring. A mechanism by which maternal exposure to cigarette smoke could increase NTD risk in offspring is suggested by several studies that show an association between cigarette smoking and elevations of homocysteine levels. Cigarette smoke during pregnancy, including secondhand exposure, can increase the risk of neural tube defects. All of the above may act by interference with some aspect of normal folic acid metabolism and folate linked methylation related cellular processes as there are multiple genes of this type associated with neural tube defects.

Triploidy affects approximately 1-2% of pregnancies, but most miscarry early in development. At birth, males with triploidy are 1.5 times more common than females.

Encephaloceles occur rarely, at a rate of one per 5,000 live births worldwide. Encephaloceles of the back of the head are more common in Europe and North America, while encephaloceles on the front of the head more frequently occur in Southeast Asia, Africa, Malaysia, and Russia. Ethnic, genetic, and environmental factors, as well as parental age, can all affect the likelihood of encephaloceles. The condition can occur in families with a family history of spina bifida.

Most fetuses with triploidy do not survive to birth, and those that do usually pass within days. As there is no treatment for Triploidy, palliative care is given if a baby survives to birth. If Triploidy is diagnosed during the pregnancy, termination is often offered as an option due to the additional health risks for the mother (preeclampsia, a life-threatening condition, or choriocarcinoma, a type of cancer). Should a mother decide to carry until term or until a spontaneous miscarriage occurs, doctors will monitor her closely in case either condition develops.

Mosaic triploidy has an improved prognosis, but affected individuals have moderate to severe cognitive disabilities.

Most patients are diagnosed by the age of 10 years and Duane's is more common in girls (60 percent of the cases) than boys (40 percent of the cases). A French study reports that this syndrome accounts for 1.9% of the population of strabismic patients, 53.5% of patients are female, is unilateral in 78% of cases, and the left eye (71.9%) is affected more frequently than the right. Around 10–20% of cases are familial; these are more likely to be bilateral than non-familial Duane syndrome. Duane syndrome has no particular race predilection.

Weismann-Netter-Stuhl syndrome, also known as Weismann-Netter Syndrome or more technically by the term tibioperoneal diaphyseal toxopachyosteosis, is a rare disorder characterized by bowing of the lower legs and an abnormal thickening of thinner bone in the leg.

The main sign is anterior bowing and posterior cortical thickening of the diaphyses of both the tibiae and fibulae. It is thought to be inherited in an autosomal dominant fashion, and is most often bilateral and symmetric in nature. Associated features include dwarfism and mild intellectual disability, as well as a process known as tibialization of the fibulae, which involves thickening and enlargement of these bones to an extent resembling the tibiae. The combination of the presence of tibialization of the fibulae, which is highly specific for the disorder, and the absence of laboratory abnormalities ruling out alternative diagnoses including rickets, essentially confirms the diagnosis.

A facial cleft is an opening or gap in the face, or a malformation of a part of the face. Facial clefts is a collective term for all sorts of clefts. All structures like bone, soft tissue, skin etc. can be affected. Facial clefts are extremely rare congenital anomalies. There are many variations of a type of clefting and classifications are needed to describe and classify all types of clefting. Facial clefts hardly ever occur isolated; most of the time there is an overlap of adjacent facial clefts.

Although the exact cause is unknown, encephaloceles are caused by failure of the neural tube to close completely during fetal development. Research has indicated that teratogens (substances known to cause birth defects), trypan blue (a stain used to color dead tissues or cells blue), and arsenic may damage the developing fetus and cause encephaloceles.

Proper levels of folic acid have been shown to help prevent such defects when taken before pregnancy, and early in pregnancy.

Empty sella syndrome (abbreviated ESS) is where the pituitary gland shrinks or becomes flattened, filling the sella turcica with cerebrospinal fluid on imaging instead of the normal pituitary. ESS can be found in the diagnostic workup of pituitary disorders, or as an incidental finding when imaging the brain.

Those at the overall highest risk for lateral medullary syndrome are men at an average age of 55.06. Having a history of hypertension, diabetes and smoking all increase the risk of large artery atherosclerosis. Large artery atherosclerosis is thought to be the greatest risk factor for lateral medullary syndrome due to the deposits of cholesterol, fatty substances, cellular waste products, calcium and fibrin. Otherwise known as plaque build up in the arteries.

In terms of management, unless the syndrome results in other medical problems, treatment for endocrine dysfunction associated with pituitary malfunction is symptomatic and thus supportive;however, in some cases, surgery may be needed.

Folic acid supplementation reduces the prevalence of neural tube defects by approximately 70% of neural tube defects indicating that 30% are not folate-dependent and are due to some cause other than alterations of methylation patterns. Multiple other genes related to neural tube defects exist which are candidates for folate insensitive neural tube defects. There are also several syndromes such as Meckel syndrome, and Triploid Syndrome which are frequently accompanied by neural tube defects that are assumed to be unrelated to folate metabolism

There is no known definitive single mechanism that causes colpocephaly. However, researchers believe there are many possible causes of colpocephaly. It is a common symptom of other neurological disorders in newborns, can be caused as a result of shunt treatment of hydrocephalus, developmental disorders in premature infants, due to intrauterine disturbances during pregnancy, genetic disorders, underdevelopment or lack of white matter in the cerebrum, and exposure of the mother and the developing fetus to medications, infections, radiation, or toxic substances. Also, it is usually more common in premature infants than in full-term infants, especially in babies born with hypoxia or lung immaturity.

Some of the central nervous system disorders which are associated with colpocephaly are as follows:

- polymicrogyria

- Periventricular leukomalacia (PVL)

- intraventricular hemorrhage

- Hydrocephalus

- schizencephaly

- microgyria

- microcephaly

- Pierre-Robin syndrome

- Neurofibromatosis

Often colpocephaly occurs as a result of hydrocephalus. Hydrocephalus is the accumulation of cerebrospinal fluid (CSF) in the ventricles or in the subarachnoid space over the brain. The increased pressure due to this condition dilates occipital horns causing colpocephaly.

The most generally accepted theory is that of neuronal migration disorders occurring during the second to fifth months of fetal life. Neuronal migration disorders are caused by abnormal migration, proliferation, and organization of neurons during early brain development. During the seventh week of gestation, neurons start proliferating in the germinal matrix which is located in the subependymal layer of the walls of the lateral ventricles. During the eighth week of gestation, the neurons then start migrating from the germinal zone to cortex along specialized radial glial fibers. Next, neurons organize themselves into layers and form synaptic contacts with other neurons present in the cortex. Under normal conditions, the neurons forming a germinal layer around ventricles migrate to the surface of the brain and form the cerebral cortex and basal ganglia. If this process is abnormal or disturbed it could result in the enlargement of the occipital horns of the lateral ventricles. Common prenatal disturbances that have been shown to disturb the neuronal migration process include the following:

- continuation of oral contraceptives

- exposure to alcohol

- intrauterine malnutrition

- intrauterine infections such as toxoplasmosis

- maternal drug ingestion during early pregnancy such as corticosteroids, salbutamol, and theophylline

Researchers also believe that these factors can cause destruction of neural elements that have previously been normally formed.

It is suggested that the underdevelopment or lack of white matter in the developing fetus could be a cause of colpocephaly. The partial or complete absence of white matter, also known as agenesis of the corpus callosum results in anatomic malformations that can lead to colpocephaly. This starts to occur around the middle of the second month to the fifth month of pregnancy. The lateral ventricles are formed as large cavities of the telencephalic vesicle. The size of the ventricles are decreased in normal development after the formation of the Foramen of Magendie, which decompresses the ventricular cavities. Myelination of the ventricular walls and association fibers of the corpus callosum and the calcarine fissure helps shape the occipital horns. In cases where this developmental process is interrupted, occipital horns are disproportionately enlarged.

Colpocephaly has been associated with chromosomal abnormalities such as trisomy 8 mosaic and trisomy 9 mosaic. A few reports of genetically transmitted colpocephaly are also found in literature. Some of these are of two siblings, monozygotic twins, and non-identical twins. The authors suggest a genetic origin with an autosomal or X-linked recessive inheritance rather than resulting from early prenatal disturbances.

The most prominent and extensively documented findings of Weismann-Netter-Stuhl syndrome are on plain radiographs of the bones. Findings include bilateral and symmetric anterior bowing of both tibiae and fibulae, lateral bowing of the tibiae, femoral bowing, and squaring of iliac and pelvis bones.