Non-progressive congenital ataxia (NPCA) is a non-progressive form of cerebellar ataxia which can occur with or without cerebellar hypoplasia.

Worster-Drought syndrome is a form of congenital suprabulbar paresis that occurs in some children with cerebral palsy. It is caused by inadequate development of the corticobulbar tracts and causes problems with the mouth and tongue including impaired swallowing. A similar syndrome in adults is called anterior opercular syndrome.

A 1986 study of a family in which multiple members had Worster-Drought Syndrome suggested it might be hereditary.

A 2000 review of cases classified Worster-Drought Syndrome as a form of cerebral palsy, caused by early damage to the brain, but identified no obvious causes during gestation or birth and found some families with a history of the condition.

The syndrome was named after Cecil Charles Worster-Drought, the doctor who discovered it in 1956.

The symptoms of phocomelia syndrome are undeveloped limbs and absent pelvic bones; however, various abnormalities can occur to the limbs and bones. Usually the upper limbs are not fully formed and sections of the "hands and arms may be missing." Short arm bones, fused fingers, and missing thumbs will often occur. Legs and feet are also affected similarly to the arms and hands. Individuals with phocomelia will often lack thigh bones, and the hands or feet may be abnormally small or appear as stumps due to their close "attachment to the body."

According to NORD, individuals carrying phocomelia syndrome will generally show symptoms of growth retardation previous to and after birth. The syndrome can also cause severe mental deficiencies in infants. Infants born with phocomelia will normally have a petite head with "sparse hair" that may appear "silvery-blonde." Hemangioma, the abnormal buildup of blood vessels, will possibly develop around the facial area at birth and the eyes may be set widely apart, a condition known as orbital hypertelorism. The pigment of the eyes will be a bluish white. Phocomelia can also cause: an undeveloped nose with slender nostrils, disfigured ears, irregularly petite jaws [also known as micrognathia], and a cleft lip with cleft palate. According to NORD, severe symptoms of phocomelia include:

- A fissure of the skull and a projecting brain known as (encephalocele)

- An accumulation of spinal fluid under the skull also known as hydrocephalus; causing vomiting and migraines

- An abnormally shaped uterus (bicornuate)

- Inability to clot blood efficiently due to a low amount of platelets running through the blood

- Malformations in the kidney and heart

- Shortened neck

- Abnormalities in the urethra

BFPP is a cobblestone-like cortical malformation of the brain. Disruptions of cerebral cortical development due to abnormal neuronal migration and positioning usually lead to cortical disorders, which includes cobblestone lissencephaly. Cobblestone lissencephaly is typically seen in three different human congenital muscular dystrophy syndromes: Fukuyama congenital muscular dystrophy, Walker-Warburg syndrome, and muscle-eye-brain disease. In cobblestone lissencephaly, the brain surface actually has a bumpy contour caused by the presence of collections of misplaced neurons and glial cells that have migrated beyond the normal surface boundaries of the brain. Sometimes regions populated by these misplaced cells have caused a radiologic misdiagnosis of polymicrogyria. However, the presence of other abnormalities in these cobblestone lissencephaly syndromes, including ocular anomalies, congenital muscular dystrophy, ventriculomegaly, and cerebellar dysplasia, usually distinguishes these disorders from polymicrogyria. There are no anatomopathologic studies that have characterized the pattern of cortical laminar alterations in patients with GPR56 gene mutations, but it has been suggested that the imaging characteristics of BFPP, including myelination defects and cerebellar cortical dysplasia, are reminiscent of those of the so-called cobblestone malformations (muscle-eye-brain disease and Fukuyama congenital muscular dystrophy) that are also associated with N-glycosylation defects in the developing brain.

Lissencephaly ("smooth brain") is the extreme form of pachygyria. In lissencephaly, few or no sulci are seen on the cortical surface, resulting in a broad, smooth appearance to the entire brain. Lissencephaly can be radiologically confused with polymicrogyria, particularly with low-resolution imaging, but the smoothness and lack of irregularity in the gray-white junction, along with markedly increased cortical thickness, distinguishes lissencephaly.

GPR56 mutation also can cause a severe encelphalopathy which is associated with electro clinical features of the Lennox-Gastaut syndrome. Lennox-Gastaut syndrome can be cryptogenic or symptomatic, but the symptomatic forms have been associated with multiple etiologies and abnormal cortical development. BFPP caused by GPR56 mutations is a representation of a malformation of cortical development that causes Lennox-Gastaut Syndrome.

Polymicrogyria usually gets misdiagnose with pacygyria so therefore it needs to be distinguished from pachygyria. Pachygyria is a distinct brain malformation in which the surface folds are excessively broad and sparse. Pachygyria and polymicrogyria may look similar on low-resolution neuroimaging such as CT because the cortical thickness can appear to be increased and the gyri can appear to be broad and smooth in both conditions. This is why higher resolution neuroimaging are needed such as an MRI.

Neuroimaging like MRI is important. However, there was considerable intrafamilial variability regarding neuroimaging, with some individuals showing normal MRI findings. Early individual prognosis of such autosomal recessive cerebellar ataxias is not possible from early developmental milestones, neurological signs, or neuroimaging.

Zori–Stalker–Williams syndrome, also known as pectus excavatum, macrocephaly, short stature and dysplastic nails, is a rare autosomal dominant congenital disorder associated with a range of features such as pectus excavatum, macrocephaly and dysplastic nails, familial short stature, developmental delay and distinctive facies. Further signs are known to be associated with this syndrome.

The name originates from the researchers who first defined and noticed the syndrome and its clinical signs.

It is believed that the syndrome is inherited in an autosomal dominant pattern, though there has been no new research undertaken for this rare disease.

There are different tests or methods used to determine GPR56 expression or visuals of the brain to analyze the specific sections that are affected. These tests for example, using animals such as mice, RNAi, Behavioral assay, Electron microscopy, CT scan, or MRI demonstrate different results that concludes an affected BFPP patient. MRI's reveal either irregularity to the cortical surface suggestive of multiple small folds or an irregular, scalloped appearance of the gray matter-white matter junction.

Neuroimaging The diagnosis of polymicrogyria is typically made by magnetic resonance imaging (MRI) since computed tomography (CT) and other imaging methods generally do not have high enough resolution or adequate contrast to identify the small folds that define the condition. The cerebral cortex often appears abnormally thick as well because the multiple small gyri are fused, infolded, and superimposed in appearance.

Neuropathology Gross neuropathologic examination reveals a pattern of complex convolutions to the cerebral cortex, with miniature gyri fused and superimposed together, often resulting in an irregular brain surface. The cortical ribbon can appear excessively thick as a result of the infolding and fusion of multiple small gyri.

Microscopic examination demonstrates that the cerebral cortex is in fact abnormally thin and has abnormal lamination; typically the cortex is unlayered or has four layers, in contrast to the normal six layers. The most superficial layers between adjacent small gyri appear fused, with the pia (layer of the meninges) bridging across multiple gyri. Prenatal diagnosis for BFPP is also available for pregnancies at risk if the GPR56 mutations have been identified in an affected family member.

Signs and symptoms of CBPS typically appear in infancy or at birth, but can appear later in childhood. These include facial diplegia (paralysis on both sides), facial muscle spasms, pseudobulbar palsy, dysarthria (difficulty speaking), difficulty chewing, dysphagia (difficulty swallowing), epilepsy, and intellectual disability. Epileptic seizures in individuals with CBPS are different between individuals and can vary between episodes.

The characteristic features of the syndrome are:

- Limitation of abduction (outward movement) of the affected eye.

- Less marked limitation of adduction (inward movement) of the same eye.

- Retraction of the eyeball into the socket on adduction, with associated narrowing of the palpebral fissure (eye closing).

- Widening of the palpebral fissure on attempted abduction. (N. B. Mein and Trimble point out that this is "probably of no significance" as the phenomenon also occurs in other conditions in which abduction is limited.)

- Poor convergence.

- A head turn to the side of the affected eye to compensate for the movement limitations of the eye(s) and to maintain binocular vision.

While usually isolated to the eye abnormalities, Duane syndrome can be associated with other problems including cervical spine abnormalities Klippel-Feil syndrome, Goldenhar syndrome, heterochromia, and congenital deafness.

Symptoms of HNA may include pain in the back, neck, arms, or shoulders, nerve pulls in the arms or back, muscular atrophy, and weakness.

Facial nerve paralysis may be divided into supranuclear and infranuclear lesions.

A simple definition of the syndrome is "limited elevation in adduction from mechanical causes around the superior oblique". This definition indicates that when the head is upright, the eye is restricted in movement due to problems with muscles and tendons that surround the eye.

Harold W. Brown characterized the syndrome in many ways such as:

- Limited elevation in the eye when head is straight up

- Eyes point out in a straight up gaze (divergence in up gaze)

- Widening of the eyelids in the affected eye on adduction

- Head tilts backwards (compensatory chin elevation to avoid double vision)

- Near normal elevation in abduction

He concluded that all of these features of Brown syndrome were due to the shortening or tightening of the anterior superior oblique tendon. Because this syndrome can be acquired or occur at random and has spontaneous resolution, Brown hypothesized one major truth for this disorder — that the short tendon sheath was due to a complete separation, congenital paresis, of the ipsilateral (on the same side) inferior oblique muscle and secondary to a permanent shortening.

After further research, he redefined the sheath syndrome into the following divisions: true sheath syndrome, which categorized only the cases that had a congenital short anterior sheath of the superior oblique tendon, and simulated sheath syndrome, which characterized all cases in which the clinical features of a sheath syndrome caused by something different other than a congenital short anterior sheath of the tendon. The clinical features of the two categories are correct but true sheath syndrome is always congenital. However, in 1970 it was discovered that a tight sheath tendon was not the cause of Brown's Syndrome. The real cause was a tight or short superior oblique tendon; studies have confirmed this and have labeled the tendon inelastic.

Phocomelia is a condition that involves malformations of the arms and legs. Although many factors can cause phocomelia, the prominent roots come from the use of the drug thalidomide and from genetic inheritance. Occurrence in an individual results in various abnormalities to the face, limbs, ears, nose, vessels and many other underdevelopments. Although operations may improve some abnormalities, many are not surgically treatable due to the lack of nerves and other related structures.

The term is from Ancient Greek φώκη "phōkē", "seal (animal)" + "-o-" interfix + μέλος "melos", "limb" + English suffix "-ia") is an extremely rare congenital disorder involving malformation of the limbs (dysmelia). Étienne Geoffroy Saint-Hilaire coined the term in 1836.

Brown's syndrome is a rare form of strabismus characterized by limited elevation of the affected eye. The disorder may be congenital (existing at or before birth), or acquired. Brown syndrome is caused by a malfunction of the Superior oblique muscle, causing the eye to have difficulty moving up, particularly during adduction (when eye turns towards the nose). Harold W. Brown first described the disorder in 1950 and initially named it the "superior oblique tendon sheath syndrome".

HNA is an episodic disorder; it is characterized by episodes generally lasting 1–6 weeks. During an episode, the nerves of the brachial plexus are targeted by the body as antigens, and the body's immune system begins to degenerate the nerves of the brachial plexus. The exact order or location of the nerve degeneration cannot be predicted before an episode. Other areas of the nervous system that have been affected are the phrenic nerves and the recurrent laryngeal. As the nerves lose function, the muscles associated with those nerves begin to atrophy. In brachial plexus degeneration, atrophy may occur in the deltoid muscles. In phrenic nerve degeneration, the diaphragm may be affected. In this case, breathing can be impaired due to a lack of muscle control of the diaphragm. If the recurrent larangyl nerve is targeted, the pharynx will begin to atrophy and voice function may be lost.

This syndrome can begin with severe shoulder or arm pain followed by weakness and numbness. Those who suffer from Parsonage–Turner experience acute, sudden-onset pain radiating from the shoulder to the upper arm. Affected muscles become weak and atrophied, and in advanced cases, paralyzed. Occasionally, there will be no pain and just paralysis, and sometimes just pain, not ending in paralysis. MRI may assist in diagnosis. Scapular winging is commonly seen.

Central facial palsy can be caused by a lacunar infarct affecting fibers in the internal capsule going to the nucleus. The facial nucleus itself can be affected by infarcts of the pontine arteries. These are corticobulbar fibers travelling in internal capsule.

Fourth cranial nerve palsy also known as Trochlear nerve palsy, is a condition affecting Cranial Nerve 4 (IV), the Trochlear Nerve, which is one of the Cranial Cranial Nerves that causes weakness or paralysis to the Superior Oblique Muscle that it innervates. This condition often causes vertical or near vertical double vision as the weakened muscle prevents the eyes from moving in the same direction together.

Because the fourth cranial nerve is the thinnest and has the longest intracranial course of the cranial nerves, it is particularly vulnerable to traumatic injury.

To compensate for the double-vision resulting from the weakness of the superior oblique, patients characteristically tilt their head down and to the side opposite the affected muscle.

When present at birth, it is known as congenital fourth nerve palsy.

Primary lymphedema is a form of lymphedema which is not directly attributable to another medical condition.

It can be divided into three forms, depending upon age of onset: congenital lymphedema, lymphedema praecox, and lymphedema tarda.

Congenital lymphedema presents at birth. Lymphedema praecox presents from ages 1 to 35. This type of lymphedema accounts for 77–94% of all cases of primary lymphedema. Lymphedema tarda presents after age 35. This type of lymphedema usually develops as a result of a developmental abnormality being precipitated by some insult such as trauma, illness, or physical immobility. Compared to secondary lymphedema, primary lymphedema is more likely to involve the face, conjunctiva, and genitalia in association with any limbs involved.

It can be familial.

Symptoms include intrinsic minus hand deformity, paralysis of intrinsic hand muscles, and C8/T1 Dermatome distribution numbness. Involvement of T1 may result in Horner's syndrome, with ptosis, and miosis. Weakness or lack of ability to use specific muscles of the shoulder or arm.It can be contrasted to Erb-Duchenne's palsy, which affects C5 and C6.

In the clinical setting, the principal difficulties in differential diagnosis arise as a consequence of the very early age at which patients with this condition first present. The clinician must be persistent in examining abduction and adduction, and in looking for any associated palpebral fissure changes or head postures, when attempting to determine whether what often presents as a common childhood squint (note-"squint" is a British term for two eyes not looking in the same direction) is in fact Duane syndrome. Fissure changes, and the other associated characteristics of Duane's such as up or down shoots and globe retraction, are also vital when deciding whether any abduction limitation is the result of Duane's and not a consequence of VI or abducens cranial nerve palsy.

Acquired Duane's syndrome is a rare event occurring after peripheral nerve palsy.

Parsonage-Turner involves neuropathy of the suprascapular nerve in 97% of cases, and variably involves the axillary and subscapular nerves. As such, the muscles usually involved are the supraspinatus and infraspinatus, which are both innervated by the suprascapular nerve. Involvement of the deltoid is more variable, as it is innervated by the axillary nerve.

Axillary nerve palsy patients present themselves with differing symptoms. For instance, some axillary nerve palsy patients complain that they cannot bend their arm at the elbow, however no other pain or discomfort exists. To further complicate diagnosis, onset of palsy can be delayed and may not be noticed until 12-24 hours after the trauma of shoulder region occurred. Therefore it is important to recognize the symptoms, but also to realize that different people have various combinations of them.

Symptoms include:

- cannot bend arm at the elbow

- deficiency of deltoid muscle function

- different regions of skin around the deltoid area can lack sensation

- unable to raise arm at the shoulder

Congenital bilateral perisylvian syndrome (CBPS) is a rare neurological disease characterized by paralysis of certain facial muscles and epileptic seizures.

The appearance of the affected arm (or arms) depends on the individual case. In some cases the arm may lack the ability to straighten or rotate but otherwise function normally giving the overall appearance of the arm to be stiff and crooked. Whereas in other circumstances the arm has little to no control and has a "loose" appearance. Treatment such as physiotherapy, massage and electrical stimulation can help to prevent this early on (or throughout) the patient's life by strengthening the arm.

In some cases, again, individuals may suffer a great deal of discomfort. For example, they may experience a severe cramping pain that lasts for some time and is particularly painful after they have slept, running from the shoulder all the way down to the wrist. Although pain does not affect everyone with Erb's Palsy, it can be extremely uncomfortable to those that it does and can even cause patients to be physically sick or faint. This extreme nerve pain is mostly common during the final stages of growth and almost always eases off in time. Other pains that Erb's Palsy sufferers might endure include strained muscle, stiffness, circulatory problems and cramp. Different factors are dependent on the severity of the condition and can vary, so whilst some patient experience a lot of pain, some patients may experience no pain at all and for their affected arm to simply be visually crooked.

Discomfort with the shoulder blade is also extremely common in Erb's palsy as the shoulder is often at risk of dislocation. This can result, again, in sickness or lack of sleep.