Facial femoral syndrome is a rare congenital disorder. It is also known as femoral dysgenesis, bilateral femoral dysgenesis, bilateral-Robin anomaly and femoral hypoplasia-unusual facies syndrome. The main features of this disorder are underdeveloped thigh bones (femurs) and unusual facial features.

Aphalangy, hemivertebrae and urogenital-intestinal dysgenesis is an extremely rare syndrome, described only in three siblings. It associates hypoplasia or aplasia of phalanges of hands and feet, hemivertebrae and various urogenital and/or intestinal abnormalities. Intrafamilial variability is important as one sister had lethal abnormalities (Potter sequence and pulmonary hypoplasia), while her affected brother was in good health with normal psychomotor development at 6 months of age. Prognosis seems to depend mainly on the severity of visceral malformations. Etiology and inheritance remain unknown.

The presenting characteristics of DDS include loss of playfulness, decreased appetite, weight loss, growth delay, abnormal skeletal development, insomnia, abdominal pain, constipation, and anuria.

Clinically, Denys–Drash is characterized by the triad of pseudohermaphroditism, mesangial renal sclerosis, and Wilms' tumor. The condition first manifests as early nephrotic syndrome and progresses to mesangial renal sclerosis, and ultimately renal failure—usually within the first three years of life.

The diagnosis is based on the combination of unusual facial features and the dysplastic or absent femurs.

Diagnosis may be made antenatally.

Bamforth–Lazarus syndrome is a genetic condition that results in thyroid dysgenesis. It is due to recessive mutations in forkhead/winged-helix domain transcription factor ("FKLH15" or "TTF2").

It is associated with "FOXE1".

Symptoms begin in infancy and include:

- hypotonia

- areflexia

- amyotrophy

- variable degrees of dysgenesis of the corpus callosum

- mild to severe intellectual and developmental delay

- psychiatric problems including paranoid delusions, depression, hallucinations and autistic-like behavior

Malouf syndrome (also known as "congestive cardiomyopathy-hypergonadotropic hypogonadism syndrome") is a congenital disorder that causes one or more of the following symptoms: mental retardation, ovarian dysgenesis, congestive cardiomyopathy, broad nasal base, blepharoptosis, and bone abnormalities, and occasionally marfanoid habitus (tall stature with long and thin limbs, little subcutaneous fat, arachnodactyly, joint hyperextension, narrow face, small chin, large testes, and hypotonia).

This disease is named after J. Malouf, who performed a case study on a family suffering from this disease in 1985.

Singleton Merten Syndrome is an autosomal dominate genetic disorder with variable expression with an onset of symptoms during childhood.

Denys–Drash syndrome (DDS) or Drash syndrome is a rare disorder or syndrome characterized by gonadal dysgenesis, nephropathy, and Wilms' tumor.

The clinical manifestations present at birth are generalized hypotonia, muscle weakness, developmental delay with mental retardation and occasional seizures. The congenital muscular dystrophy is characterized by hypoglycosylation of α-dystroglycan.

Those born with the disease also experience severe ocular and brain defects. Half of all children with WWS are born with encephalocele, which is a gap in the skull that will not seal. The meninges of the brain protrude through this gap due to the neural tube failing to close during development. A malformation of the a baby's cerebellum is often a sign of this disease.Common ocular issues associated with WWS are abnormally small eyes and retinal abnormalities cause by an underdeveloped light-sensitive area in the back of the eye.

Cerebral dysgenesis–neuropathy–ichthyosis–keratoderma syndrome (also known as "CEDNIK syndrome") is a cutaneous condition caused by mutation in the SNAP29 gene.

Clinical:

Patients often present with a history of fever of unknown origin, muscular weakness, poor development, abnormal dentition, normal serum calcium, phosphorus, and alkaline phosphatase levels. Associated clinical findings also include glaucoma, photosensitivity, heart block, foot deformities, and chronic psoriasiform skin lesions.

Radiological:

Classic radiologic findings were first described by Edward B. Singleton and David Merten in 1973.

Typical radiographic appearances include skeletal demineralization, expanded shafts of the metacarpals and phalanges with widenend medullary cavities, cardiomegaly, and intramural calcification of the proximal aorta with occasional extension into the aortic or mitral valves.

Other commonly seen radiographic findings include shallow acetabular fossa, subluxation of the femoral head, coxa valga, hypoplastic radial epiphysis, soft tissue calcifications between the radius and ulna, constriction of the proximal radial shaft, acro-osteolysis, and equinovarus foot deformities.

Andermann syndrome also known as agenesis of corpus callosum with neuronopathy (ACCPN), Charlevoix disease among others is a very rare neurodegenerative genetic disorder that damages the nerves used to control muscles and related to sensation, and is often associated with agenesis of the corpus collosum.

It was first described by Eva Andermann et al. in 1972.

Tooth and nail syndrome (also known as "Hypodontia with nail dysgenesis," and "Witkop syndrome") is a rare disorder, first described in 1965, characterized by nails that are thin, small, and friable, and which may show koilonychia at birth.

It is associated with "MSX1".

Walker–Warburg syndrome (WWS), also called Warburg syndrome, Chemke syndrome, HARD syndrome (Hydrocephalus, Agyria and Retinal Dysplasia), Pagon syndrome, cerebroocular dysgenesis (COD) or cerebroocular dysplasia-muscular dystrophy syndrome (COD-MD), is a rare form of autosomal recessive congenital muscular dystrophy. It is associated with brain (lissencephaly, hydrocephalus, cerebellar malformations) and eye abnormalities. This condition has a worldwide distribution. The overall incidence is unknown but a survey in North-eastern Italy has reported an incidence rate of 1.2 per 100,000 live births. It is the most severe form of congenital muscular dystrophy with most children dying before the age of three years.

Renal-hepatic-pancreatic dysplasia is an autosomal recessive congenital disorder characterized by pancreatic fibrosis, renal dysplasia and hepatic dysgenesis. It is usually fatal soon after birth.

An association with NPHP3 has been described.

It was characterized in 1959.

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.

Characteristics are:

- A fibrous band instead of the fibula

- Short deformed leg

- Absence of the lateral part of the ankle joint (due to absence of the distal end of the fibula), and what is left is unstable; the foot has an equinovalgus deformity

- Possible absence of part of the foot requiring surgical intervention to bring the foot into normal function, or amputation.

- Possible absence of one or two toes on the foot

- Possible conjoined toes or metatarsals

Partial or total absence of fibula is among the most frequent limb anomalies. It is the most common long bone deficiency and is the most common skeletal deformity in the leg. It most often is unilateral (present only on one side). It may also present as bilateral (affecting both legs). Paraxial fibular hemimelia is the most common manifestation in which only the postaxial portion of the limb is affected. It is commonly seen as a complete terminal deficiency, where the lateral rays of the foot are also affected. Hemimelia can also be intercalary in which case the foot remains unaffected. Although the missing bone is easily identified, this condition is not simply a missing bone. Males are affected twice as often as females in most series.

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.

The disease is characterized by Perthes-like pelvic anomalies (premature closure of the capital femoral epiphyses and widened femoral necks with flattened femoral heads), enchondromata and ecchondromata.

Cleidocranial dysostosis is a general skeletal condition so named from the collarbone (cleido-) and cranium deformities which people with it often have.

People with the condition usually present with a painless swelling in the area of the clavicles at 2–3 years of age. Common features are:

- Clavicles (collarbones) can be partly missing leaving only the medial part of the bone. In 10% cases, they are completely missing. If the collarbones are completely missing or reduced to small vestiges, this allows hypermobility of the shoulders including ability to touch the shoulders together in front of the chest. The defect is bilateral 80% of the time. Partial collarbones may cause nerve damage symptoms and therefore have to be removed by surgery.

- The mandible is prognathic due to hypoplasia of maxilla (micrognathism) and other facial bones.

- A soft spot or larger soft area in the top of the head where the fontanelle failed to close, or the fontanelle closes late.

- Bones and joints are underdeveloped. People are shorter and their frames are smaller than their siblings who do not have the condition.

- The permanent teeth include supernumerary teeth. Unless these supernumeraries are removed they will crowd the adult teeth in what already may be an underdeveloped jaw. If so, the supernumeraries will probably need to be removed to make space for the adult teeth. Up to 13 supernumarary teeth have been observed. Teeth may also be displaced. Cementum formation may be deficient.

- Failure of eruption of permanent teeth.

- Bossing (bulging) of the forehead.

- Open skull sutures, large fontanelles.

- Hypertelorism.

- Delayed ossification of bones forming symphysis pubis, producing a widened symphysis.

- Coxa vara can occur, limiting abduction and causing Trendelenburg gait.

- Short middle fifth phalanges, sometimes causing short and wide fingers.

- Vertebral abnormalities.

- On rare occasions, brachial plexus irritation can occur.

- Scoliosis, spina bifida and syringomyelia have also been described.

Other features are: parietal bossing, basilar invagination (atlantoaxial impaction), persistent metopic suture, abnormal ear structures with hearing loss, supernumerary ribs, hemivertebrae with spondylosis, small and high scapulae, hypoplasia of illiac bones, absence of the pubic bone, short / absent fibular bones, short / absent radial bones, hypoplastic terminal phalanges.

Upington disease, also called Perthes-like hip disease, enchondromata, ecchondromata, and familial dyschondroplasia, is an extremely rare autosomal dominant malformation disorder. It has only one published source claiming its existence in three generations of one family from South Africa.

Congenital cystic eye (also known as "CCE" or "cystic eyeball") is an extremely rare ocular malformation where the eye fails to develop correctly "in utero" and is replaced by benign, fluid-filled tissue. Its incidence is unknown, due to the very small number of cases reported. An audit by Duke-Elder of the medical literature from 1880 to 1963 discovered only 28 cases. The term was coined in 1937 by the renowned ophthalmologist Ida Mann.

Embryologically, the defect is thought to occur around day 35 of gestation, when the vesicle fails to invaginate. Dysgenesis of the vesicle later in development may result in coloboma, a separate and less severe malformation of the ocular structures.

CCE is almost always unilateral, but at least 2 cases of bilateral involvement have been described. Patients may also present with skin appendages attached to the skin surrounding the eyes. Association with intracranial anomalies has been reported.

Treatment of CCE is usually by enucleation, followed by insertion of an ocular implant and prosthesis.

Fibular hemimelia or longitudinal fibular deficiency is "the congenital absence of the fibula and it is the most common congenital absence of long bone of the extremities." It is the shortening of the fibula at birth, or the complete lack thereof. In humans, the disorder can be noted by ultrasound in utero to prepare for amputation after birth or complex bone lengthening surgery. The amputation usually takes place at six months with removal of portions of the legs to prepare them for prosthetic use. The other treatments which include repeated corrective osteotomies and leg-lengthening surgery (Ilizarov apparatus) are costly and associated with residual deformity.

Acorea or fibrous occlusion of the pupil, microphthalmia and cataracts are present in both eyes. Microcornea and iridocorneal dysgenesis also occur. The retina and optic disc are normal.