There is no causative / curative therapy. Symptomatic medical treatments are focussing on symptoms caused by orthopaedic, dental or cardiac problems. Regarding perioperative / anesthesiological management, recommendations for medical professionals are published at OrphanAnesthesia.

Ellis–van Creveld Syndrome (also called "chondroectodermal dysplasia" or "mesoectodermal dysplasia" but see 'Nomenclature' section below) is a rare genetic disorder of the skeletal dysplasia type.

Meleda disease (MDM) or "mal de Meleda", also called Mljet disease, keratosis palmoplantaris and transgradiens of Siemens, (also known as "Acral keratoderma," "Mutilating palmoplantar keratoderma of the Gamborg-Nielsen type," "Palmoplantar ectodermal dysplasia type VIII", and "Palmoplantar keratoderma of the Norrbotten type") is an extremely rare autosomal recessive congenital skin disorder in which dry, thick patches of skin develop on the soles of the hands and feet, a condition known as palmoplantar hyperkeratosis.

MDM is most common on the Dalmatian island of Mljet (or "Meleda"), thought to be because of a founder effect. It is of autosomal recessive inheritance. It may be caused by a mutation on the "SLURP1" gene, located on chromosome 8.

Individuals affected by certain ED syndromes cannot perspire. Their sweat glands may function abnormally or may not have developed at all because of inactive proteins in the sweat glands. Without normal sweat production, the body cannot regulate temperature properly. Therefore, overheating is a common problem, especially during hot weather. Access to cool environments is important.

Ectodermal dysplasia is not a single disorder, but a group of syndromes all deriving from abnormalities of the ectodermal structures. More than 150 different syndromes have been identified.

Despite some of the syndromes having different genetic causes the symptoms are sometimes very similar. Diagnosis is usually by clinical observation often with the assistance of family medical histories so that it can be determined whether transmission is autosomal dominant or recessive.

Worldwide around 7,000 people have been diagnosed with an ectodermal dysplasia condition. Some ED conditions are only present in single family units and derive from very recent mutations. Ectodermal dysplasias can occur in any race but are much more prevalent in Caucasians than any other group and especially in fair caucasians.

Ectodermal dysplasias are described as "heritable conditions in which there are abnormalities of two or more ectodermal structures such as the hair, teeth, nails, sweat glands, salivary glands, cranial-facial structure, digits and other parts of the body."

Naxos disease (also known as "Diffuse non-epidermolytic palmoplantar keratoderma with woolly hair and cardiomyopathy," "Diffuse palmoplantar keratoderma with woolly hair and arrhythmogenic right ventricular cardiomyopathy firstly described in Naxos island by Dr Nikos Protonotarios," and "Naxos disease") is a cutaneous condition characterized by a palmoplantar keratoderma. The prevalence of the syndrome is about 1 person in 1000 in the Hellenic islands.

It has been associated with mutations in the genes encoding desmoplakin and plakoglobin.

Gigantiform cementoma is a rare, autosomal dental tumor. It is benign, but without intervention it can result in severe disfigurement of the jaw. The cause of this tumor is currently unknown. This is an exceedingly rare tumor with only a handful of documented cases worldwide. The most famous case is of Novemthree Siahaan (who died on September 15, 2005), a young Indonesian boy from Batam Island who received medical care in Haulien, Taiwan through a Buddhist missionary from the Tzu Chi Foundation, which was documented on the Discovery Health Channel. Another famous case is a young Korean girl named Ayun Lee (August 26, 2003~) and her father Young-hak Lee whose case has shown that the tumor can be heritable. She is currently under treatment, which she may need to continue until her growth stops in her early 20s.

The term has been used in the past to describe florid cemento-osseous dysplasia, but it is now reserved for an autosomal dominant condition affecting the maxillae. It affects mostly Caucasian people under the age of 10. Treatment is difficult. Surgical removal of the affected bone is needed, and has to be followed by reconstruction.

Affected individuals may benefit from autologous fat transfer or fat grafts to restore a more normal contour to the face. However, greater volume defects may require microsurgical reconstructive surgery which may involve the transfer of an island parascapular fasciocutaneous flap or a free flap from the groin, rectus abdominis muscle (Transverse Rectus Abdominis Myocutaneous or "TRAM" flap) or latissimus dorsi muscle to the face. Severe deformities may require additional procedures, such as pedicled temporal fascia flaps, cartilage grafts, bone grafts, orthognathic surgery, and bone distraction. The timing of surgical intervention is controversial; some surgeons prefer to wait until the disease has run its course while others recommend early intervention.

Medical management may involve immunosuppressive drugs such as methotrexate, corticosteroids, cyclophosphamide, and azathioprine. No randomized controlled trials have yet been conducted to evaluate such treatments, so the benefits have not been clearly established.

There is no known treatment for FTS, as the cause is not yet known. There are conflicting reports on whether the paralysis is reversible; some sources claim that moving an elephant away from the area in which it contracted the condition will allow it to recover, while others claim that damage to the trunk is irreversible.

In some extreme cases, wildlife managers have killed affected elephants for humane reasons.

There is no cure for XDP and medical treatment offers only temporary relief. Some authors have reported benzodiazepines and anticholinergic agents in the early stages of the disease. Botulinum toxin injections have been used to relieve focal dystonia. Deep brain stimulation has shown promise in the few cases treated surgically.

X-linked dystonia parkinsonism (XDP), also known as Lubag Syndrome or X-linked Dystonia of Panay, is a rare x-linked progressive movement disorder with high penetrance found almost exclusively in males from the Panay, Philippines. It is characterized by dystonic movements first typically occurring in the 3rd and 4th decade of life. The dystonic movements often either coexist or develop into parkinsonism within 10 years of disease onset.

The opioid antagonist naloxone allowed a woman with congenital insensitivity to pain to experience it for the first time. Similar effects were observed in Na1.7 null mice treated with naloxone. As such, opioid antagonists like naloxone and naltrexone may be effective in treating the condition.

Congenital insensitivity to pain is found in Vittangi, a village in Kiruna Municipality in northern Sweden, where nearly 40 cases have been reported. A few Americans also have it.

Lucio Godina (March 8, 1908 – November 24, 1936) and Simplicio Godina (March 8, 1908 - December 8, 1936) were pygopagus conjoined twins from the island of Samar in the Philippines.

At the age of 21 they married Natividad and Victorina Matos, who were identical twins. They performed in various sideshow acts, including in an orchestra on Coney Island and in dance with their wives.

After Lucio died of rheumatic fever in New York City, doctors operated to separate him from Simplicio. Simplicio survived the operation, but died shortly thereafter due to spinal meningitis.

Polymelia (from Greek πολυ- = "many" plus μέλος (plural μέλεα) = "limb") also known as "hydra syndrome" is a birth defect involving limbs (a type of dysmelia), in which the affected individual has more than the usual number of limbs. In humans and most land-dwelling animals, this means having five or more limbs. The extra limb is most commonly shrunken and/or deformed.

Sometimes an embryo started as conjoined twins, but one twin degenerated completely except for one or more limbs, which end up attached to the other twin.

Sometimes small extra legs between the normal legs are caused by the body axis forking in the dipygus condition.

Floppy trunk syndrome was initially observed in 1989 on Fothergill Island, in Matusadona National Park, Zimbabwe, near Lake Kariba. Five more cases were observed in the same location around a year later, and several more cases were observed in July and August 1992. Several elephants suffering from the condition were surgically biopsied while paralyzed in May 1989, and a necropsy of affected elephants was performed in November 1991 and April 1992.

There are several proposed explanations for the mechanism which produces such dwarfism.

One is a selective process where only smaller animals trapped on the island survive, as food periodically declines to a borderline level. The smaller animals need fewer resources and smaller territories, and so are more likely to get past the break-point where population decline allows food sources to replenish enough for the survivors to flourish. Smaller size is also advantageous from a reproductive standpoint, as it entails shorter gestation periods and generation times.

In the tropics, small size should make thermoregulation easier.

Among herbivores, large size confers advantages in coping with both competitors and predators, so a reduction or absence of either would facilitate dwarfing; competition appears to be the more important factor.

Among carnivores, the main factor is thought to be the size and availability of prey resources, and competition is believed to be less important. In tiger snakes, insular dwarfism occurs on islands where available prey is restricted to smaller sizes than are normally taken by mainland snakes. Since prey size preference in snakes is generally proportional to body size, small snakes may be better adapted to take small prey.

An enostosis or bone island is a small area of compact bone within the cancellous bone. They are commonly seen as an incidental finding on radiographs or CT scans. They are typically very small and do not cause any symptoms. No treatment is necessary. Multiple enostoses are present in osteopoikilosis.

Insular dwarfism, a form of phyletic dwarfism, is the process and condition of the reduction in size of large animals over a number of generations when their population's range is limited to a small environment, primarily islands. This natural process is distinct from the intentional creation of dwarf breeds, called dwarfing. This process has occurred many times throughout evolutionary history, with examples including dinosaurs, like "Europasaurus", and modern animals such as elephants and their relatives. This process, and other "island genetics" artifacts, can occur not only on traditional islands, but also in other situations where an ecosystem is isolated from external resources and breeding. This can include caves, desert oases, isolated valleys and isolated mountains ("sky islands"). Insular dwarfism is one aspect of the more general "island rule", which posits that when mainland animals colonize islands, small species tend to evolve larger bodies, and large species tend to evolve smaller bodies.

There are drugs that can increase serum HDL such as niacin or gemfibrozil. While these drugs are useful for patients with hyperlipidemia, Tangier's disease patients do not benefit from these pharmaceutical interventions.

Therefore, the only current treatment modality for Tangier's disease is diet modification. A low-fat diet can reduce some of the symptoms, especially those involving neuropathies.

Coconut cadang-cadang disease has no treatment yet. However, chemotherapy with antibiotics has been tried with tetracycline solutions; antibiotics failed trying to alter progress of the disease since they had no significant effect on any of the studied parameters. When the treated plants were at the early stage, tetracycline injections failed to prevent the progression of the palms to more advanced stages, nor did they affect significantly the mean number of spathes or nuts. Penicillin treatment had no apparent improvement either.

Control strategies are elimination of reservoir species, vector control, mild strain protection and breeding for host resistance. Eradication of diseased plants is usually performed to minimize spread but is of dubious efficacy due to the difficulties of early diagnosis as the virus etiology remains unknown and the one discovered are the three main stages in the disease development.

During the latest outbreak of the disease (2004), several treatment methods were tested. Main treatment involved the administration of antibiotics, in some cases glucose solution or dietary mixtures were additionally supplemented. Outcome of the different treatment methods varied greatly. Especially the success of antibiotic treatment and a widespread use on wild animals remains a matter of debate.

There is no known "cure" for PDD-NOS, but there are interventions that can have a positive influence. Early and intensive implementation of evidence-based practices and interventions are generally believed to improve outcomes. Most of these are individualized special education strategies rather than medical or pharmaceutical treatment; the best outcomes are achieved when a team approach among supporting individuals is utilized.

Some of the more common therapies and services include:

- Visual and environmental supports, visual schedules

- Applied behavior analysis

- Discrete trial instruction (part of applied behavior analysis)

- Social stories and comic strip conversations

- Physical and occupational therapy