Surgery to separate conjoined twins may range from very easy to very difficult depending on the point of attachment and the internal parts that are shared. Most cases of separation are extremely risky and life-threatening. In many cases, the surgery results in the death of one or both of the twins, particularly if they are joined at the head or share a vital organ. This makes the ethics of surgical separation, where the twins can survive if not separated, contentious. Alice Dreger of Northwestern University found the quality of life of twins who remain conjoined to be higher than is commonly supposed. Lori and George Schappell and Abby and Brittany Hensel are notable examples.

In 1955, neurosurgeon Harold Voris (1902-1980) and his team at Mercy Hospital in Chicago performed the first successful operation to separate Siamese twins conjoined (Craniopagus twins) at the head, which resulted in long-term survival for both. The larger girl was reported in 1963 as developing normally, but the smaller was permanently impaired.

In 1957, Bertram Katz and his surgical team made international medical history performing the world's first successful separation of conjoined twins sharing a vital organ. Omphalopagus twins John Nelson and James Edward Freeman (Johnny and Jimmy) were born to Mr. and Mrs. William Freeman of Youngstown, Ohio, on April 27, 1956. The boys shared a liver but had separate hearts and were successfully separated at North Side Hospital in Youngstown, Ohio by Bertram Katz. The operation was funded by the Ohio Crippled Children's Service Society.

Recent successful separations of conjoined twins include that of the separation of Ganga & Jamuna Shreshta in 2001, who were born in Kathmandu, Nepal, in 2000. The 197-hour surgery on the pair of craniopagus twins was a landmark one which took place in Singapore; the team was led by neurosurgeons Chumpon Chan and Keith Goh. The surgery left Ganga with brain damage and Jamuna unable to walk. Seven years later, Ganga Shrestha died at the Model Hospital in Kathmandu in July 2009, at the age of 8, three days after being admitted for treatment of a severe chest infection.

A case of particular interest was that of infants Rose and Grace ("Mary" and "Jodie") Attard, conjoined twins from Malta who were separated in Great Britain by court order over the religious objections of their parents, Michaelangelo and Rina Attard. The surgery took place in November, 2000, at St Mary's Hospital in Manchester. The operation was controversial because Rose, the weaker twin, would die as a result of the procedure as her heart and lungs were dependent upon Grace's. (The twins were attached at the lower abdomen and spine.) However, if the operation had not taken place, it was certain that both twins would die. Grace survived to enjoy a normal childhood.

In 2003 two 29-year-old women from Iran, Ladan and Laleh Bijani, who were joined at the head but had separate brains (craniopagus) were surgically separated in Singapore, despite surgeons' warnings that the operation could be fatal to one or both. Their complex case was accepted only because high tech graphical imagery and modelling would allow the medical team to plan the risky surgery. Unfortunately, an undetected major vein hidden from the scans was discovered during the operation. The separation was completed but both women died while still in surgery on July 8, 2003.

Many factors determine the optimal way to deliver a baby. A vertex presentation is the ideal situation for a vaginal birth, however, occiput posterior positions tend to proceed more slowly, often requiring an intervention in the form of forceps, vacuum extraction, or Cesarean section. In a large study, a majority of brow presentations were delivered by Cesarean section, however, because of 'postmaturity', factors other than labour dynamics may have played a role. Most face presentations can be delivered vaginally as long as the chin is anterior; there is no increase in fetal or maternal mortality. Mento-posterior positions cannot be delivered vaginally in most cases (unless rotated) and are candidates for Cesarean section in contemporary management.

"'Conjoined twins" are identical twins joined in utero. An extremely rare phenomenon, the occurrence is estimated to range from 1 in 49,000 births to 1 in 189,000 births, with a somewhat higher incidence in Southeast Asia and Africa. Approximately half are stillborn, and an additional one-third die within 24 hours. Most live births are female, with a ratio of 3:1.

Two contradicting theories exist to explain the origins of conjoined twins. The more generally accepted theory is "fission", in which the fertilized egg splits partially. The other theory, no longer believed to be the basis of conjoined twinning, is fusion, in which a fertilized egg completely separates, but stem cells (which search for similar cells) find like-stem cells on the other twin and fuse the twins together. Conjoined twins share a single common chorion, placenta, and amniotic sac, although these characteristics are not exclusive to conjoined twins as there are some monozygotic but non-conjoined twins who also share these structures in utero.

The most famous pair of conjoined twins was Chang and Eng Bunker (Thai: อิน-จัน, In-Chan) (1811–1874), Thai brothers born in Siam, now Thailand. They traveled with P.T. Barnum's circus for many years and were labeled as the Siamese twins. Chang and Eng were joined at the torso by a band of flesh, cartilage, and their fused livers. In modern times, they could have been easily separated. Due to the brothers' fame and the rarity of the condition, the term "Siamese twins" came to be used as a synonym for conjoined twins.

The primary goal in surgical intervention is to allow normal cranial vault development to occur. This can be achieved by excision of the prematurely fused suture and correction of the associated skull deformities. If the synostosis goes uncorrected, the deformity will progressively worsen not only threatening the aesthetic aspect, but also the functional aspect. This is especially the case in the asymmetric conditions, such as unilateral coronal synostosis, with compromised function of the eyes and the jaw.

In addition signs of compromised neurodevelopment have been seen amongst all the synostoses, although this may also be caused by primary maldevelopment of the brain and can thus not be prevented by surgical intervention.

There are a few basic elements involved in the surgical intervention aimed at normalization of the cranial vault.

- One is minimization of blood loss, which is attempted by injection of vasoconstrictive agents (i.e. epinephrine) seven to ten minutes before scalp incision. In addition is the initiation of surgery delayed until blood products are physically present in the operating room.

- Another general agreement is the avoidance of the use of titanium plates in the fixation of the skull. The complication following this procedure is gradual movement of the titanium plates towards the brain, induced by resorption of the innermost bone layer of the skull and deposition of new bone on the outermost layer, thereby integrating the titanium plates. In some cases, the plates were even seen coming in direct contact with the brain. Absorbable plates are now used instead.

The prevention of the complications mentioned above plays an important role in the discussion about the timing of the surgery. The general consensus is now to perform surgery in late infancy, i.e. between six and twelve months. In this time frame the efficacy of surgery is enhanced due to several reasons:

- The bone is still more malleable and can be remodelled relatively 'simply' by greenstick fractures of the bone. At approximately one year of age the bone has become more mineralized and brittle and needs to be fastened to the surrounding bone with sutures or an absorbable plate.

- Reshaping of the cranial vault most commonly means excision of the bones and adjustment of the shape. Replacement of the bones can leave 'gaps' which are readily re-ossified before the age of one year, but need bony filling thereafter.

The reason why most surgeons will not intervene until after the age of six months is the greater risk that blood loss poses before this age. If possible it is preferred to wait until after three months of age when the anaesthetic risks are decreased.

Surgery is not performed in early childhood in every country. In some countries surgical intervention can take place in the late teens.

It is important that families seek out a Pediatric Craniofacial Physician who has experience with craniosynostosis for proper diagnosis, surgical care, and followup.

There are several options for treatment of mouth anomalies like Tessier cleft number 2-3-7 . These clefts are also seen in various syndromes like Treacher Collins syndrome and hemifacial microsomia, which makes the treatment much more complicated. In this case, treatment of mouth anomalies is a part of the treatment of the syndrome.

The outcome of this disease is dependent on the severity of the cardiac defects. Approximately 1 in 3 children with this diagnosis require shunting for the hydrocephaly that is often a consequence. Some children require extra assistance or therapy for delayed psychomotor and speech development, including hypotonia.

There is no single strategy for treatment of facial clefts, because of the large amount of variation in these clefts. Which kind of surgery is used depends on the type of clefting and which structures are involved. There is much discussion about the timing of reconstruction of bone and soft tissue. The problem with early reconstruction is the recurrence of the deformity due to the intrinsic restricted growth. This requires additional operations at a later age to make sure all parts of the face are in proportion. A disadvantage of early bone reconstruction is the chance to damage the tooth germs, which are located in the maxilla, just under the orbit. The soft tissue reconstruction can be done at an early age, but only if the used skin flap can be used again during a second operation. The timing of the operation depends on the urgency of the underlying condition. If the operation is necessary to function properly, it should be done at early age. The best aesthetic result is achieved when the incisions are positioned in areas which attract the least attention (they cover up the scars). If, however, the function of a part of the face isn’t damaged, the operation depends on psychological factors and the facial area of reconstruction.

The treatment plan of a facial cleft is planned right after diagnosis. This plan includes every operation needed in the first 18 years of the patients life to reconstruct the face fully.

In this plan, a difference is made between problems that need to be solved to improve the health of the patient (coloboma) and problems that need to be solved for a better cosmetic result (hypertelorism).

The treatment of the facial clefts can be divided in different areas of the face: the cranial anomalies, the orbital and eye anomalies, the nose anomalies, the midface anomalies and the mouth anomalies.

No treatment is available for most of these disorders. Mannose supplementation relieves the symptoms in PMI-CDG (CDG-Ib) for the most part, even though the hepatic fibrosis may persist. Fucose supplementation has had a partial effect on some SLC35C1-CDG (CDG-IIc or LAD-II) patients.

Treatment of Wiskott–Aldrich syndrome is currently based on correcting symptoms. Aspirin and other nonsteroidal anti-inflammatory drugs should be avoided, since these may interfere with platelet function. A protective helmet can protect children from bleeding into the brain which could result from head injuries. For severely low platelet counts, patients may require platelet transfusions or removal of the spleen. For patients with frequent infections, intravenous immunoglobulins (IVIG) can be given to boost the immune system. Anemia from bleeding may require iron supplementation or blood transfusion.

As Wiskott–Aldrich syndrome is primarily a disorder of the blood-forming tissues, a hematopoietic stem cell transplant, accomplished through a umbilical cord blood or bone marrow transplant offers the only current hope of cure. This may be recommended for patients with HLA-identical donors, matched sibling donors, or even in cases of incomplete matches if the patient is age 5 or under.

Studies of correcting Wiskott–Aldrich syndrome with gene therapy using a lentivirus have begun.

Proof-of-principle for successful hematopoietic stem cell gene therapy has been provided for patients with Wiskott–Aldrich syndrome.

Currently, many investigators continue to develop optimized gene therapy vectors. In July 2013 the Italian San Raffaele Telethon Institute for Gene Therapy (HSR-TIGET) reported that three children with Wiskott–Aldrich syndrome showed significant improvement 20–30 months after being treated with a genetically modified lentivirus. In April 2015 results from a follow-up British and French trial where six children with Wiskott–Aldrich syndrome were treated with gene therapy were described as promising. Median follow-up time was 27 months.

In order to prevent further cysts and infections from forming, the thyroglossal duct and all of its branches are removed from the throat and neck area. A procedure, known as the Sistrunk procedure, is considered to be the standard procedure and involves removal of portions of the hyoid bone and core tissue of the suprahyoid region. Cysts will often reoccur if the entire duct is not removed, so reoccurrence requires a wider range of tissue to be removed in a subsequent surgery.

Delaying the surgical procedure almost always leads to recurrent infections, which will continue to delay the needed treatment. The Sistrunk procedure has a reoccurrence rate of less than 5%, proving it is extremely effective at removing the majority of traces of the persistent thyroglossal duct.

Coffin birth, also known as postmortem fetal extrusion, is the expulsion of a nonviable fetus through the vaginal opening of the decomposing body of a deceased pregnant woman as a result of the increasing pressure of intra-abdominal gases. This kind of postmortem delivery occurs very rarely during the decomposition of a body. The practice of chemical preservation, whereby chemical preservatives and disinfectant solutions are pumped into a body to replace natural body fluids (and the bacteria that reside therein), have made the occurrence of "coffin birth" so rare that the topic is rarely mentioned in international medical discourse.

Typically during the decomposition of a human body, naturally occurring bacteria in the organs of the abdominal cavity (such as the stomach and intestines) generate gases as by-products of metabolism, which causes the body to swell. In some cases, the confined pressure of the gases can squeeze the uterus (the womb), even forcing it downward, and it may and be forced out of the body through the vaginal opening (a process called "prolapse"). If a fetus is contained within the uterus, it could therefore be expelled from the mother's body through the vaginal opening when the uterus turns inside-out, in a process that, to outward appearances, mimics childbirth. The main differences lie in the state of the mother and fetus and the mechanism of delivery: in the event of natural, live childbirth, the mother's contractions encourage the infant to emerge from the womb; in a case of coffin birth, built-up gas pressure within the putrefied body of a pregnant woman pushes the dead fetus from the body of the mother.

Cases have been recorded by medical authorities since the 16th century, though some archaeological cases provide evidence for its occurrence in many periods of human history. While cases of postmortem fetal expulsion have always been rare, the phenomenon has been recorded under disparate circumstances and is occasionally seen in a modern forensic context when the body of a pregnant woman lies undisturbed and undiscovered for some time following death. There are also cases whereby a fetus may become separated from the body of the pregnant woman about the time of death or during decomposition, though because those cases are not consistent with the processes described here, they are not considered true cases of postmortem fetal extrusion.

Ilona and Judit Gófitz (Hungarian: "Gófitz Ilona" és "Judit"; in contemporary publications: "Helen" and "Judith of Szőny"), also known as the Hungarian Sisters, were conjoined twins from Szőny, Hungary who lived from October 19, 1701 to February 8, 1723. In the image they appear to be pygopagus.

Ganga and Jamuna Mondal (born Ayara and Jayara Ratun, 1969 or 1970), known professionally as The Spider Girls and The Spider Sisters, are conjoined twins from a Bengali family in Basirhat, West Bengal, India.

Prognoses for 3C syndrome vary widely based on the specific constellation of symptoms seen in an individual. Typically, the gravity of the prognosis correlates with the severity of the cardiac abnormalities. For children with less severe cardiac abnormalities, the developmental prognosis depends on the cerebellar abnormalities that are present. Severe cerebellar hypoplasia is associated with growth and speech delays, as well as hypotonia and general growth deficiencies.

The twins require the use of wheelchairs for mobility and are unable to speak without the assistance of electronic speaking aids. They experience persistent and painful muscle spasms which are worsened by emotional distress. They are currently living with their parents, with the assistance of hospice workers. Doctors continue to administer tests to the twins in search of a treatment.

The cause of postmortem fetal extrusion is not completely understood, as the event is neither predictable nor replicable under experimental conditions. Evidence has accumulated opportunistically and direct observation is serendipitous. While it is possible that more than one cause can produce the same result, there is an accepted hypothesis, based on established research in the fields of biochemistry and forensic taphonomy, and further supported by observational research, that accounts for the taphonomic mechanisms that would result in the most often encountered cases of postmortem extrusion of a non-viable fetus.

Typically, as a dead body decomposes, body tissues become depleted of oxygen and the body begins to putrefy; anaerobic bacteria in the gastrointestinal tract proliferate and as a result of increased metabolic activity, release gases such as carbon dioxide, methane, and hydrogen sulfide. These bacteria secrete exoenzymes to break down body cells and proteins for ingestion which thus weakens organ tissues. Increasing pressure forces the diffusion of excessive gases into the weakened tissues where they enter the circulatory system and spread to other parts of the body, causing both torso and limbs to become bloated. These decompositional processes weaken the structural integrity of organs by separating necrotizing tissue layers. Bloating usually begins from two to five days after death, depending on external temperature, humidity, and other environmental conditions. As the volume of gas increases, the pressure begins to force various body fluids to exude from all natural orifices. It is at this point during the decomposition of a pregnant body that amniotic membranes become stretched and separated, and intraabdominal gas pressure may force the and prolapse of the uterus, which would result in the expulsion of the fetus through the vaginal canal. It has been observed that the bodies of multiparous women are more likely to spontaneously expel the fetus during decomposition than those who died during their first pregnancy, because of the more elastic nature of the cervix.

First options for treatment are conservative, using hot or cold packs, rest and NSAID's at first. If no improvement is made, a splint or brace can be used to keep the deviated arm straight. When none of the conservative treatments work surgical intervention is designated.

The twins are joined at the abdomen and pelvis, have four arms, and three legs, two of which are fused into a single, nine-toed limb, which remains concealed behind their body. They share a stomach, but have two hearts, two kidneys, one liver, and one reproductive tract.

The twins have been examined by doctors to determine whether or not they can be separated. However, they have no plans to do so because they feel it would be against God's will, carry too great a medical risk, and would rob them of their employment. They have stated ""We are happy as we are. The family will starve if we are separated.""

Ladan and Laleh Bijani (in Persian: ) (January 17, 1974 – July 8, 2003) were Iranian conjoined twin sisters. They were joined at the head and died immediately after their complicated surgical separation. Coincidentally, the twins were born 100 years to the day of the deaths of Chang and Eng Bunker, also conjoined twins, famously known as the "original" Siamese twins.

Fryns syndrome is an autosomal recessive multiple congenital anomaly syndrome that is usually lethal in the neonatal period. Fryns (1987) reviewed the syndrome.

"Ulna reduction"

Adults with Madelung’s deformity may suffer from ulnar-sided wrist pain. Madelung's Deformity is usually treated by treating the distal radial deformity. However, if patients have a positive ulnar variance and focal wrist pathology, it’s possible to treat with an isolated ulnar-shortening osteotomy. In these patients the radial deformity is not treated.

The ulna is approached from the subcutaneous border. A plate is attached to the distal end of the ulna, to plan the osteotomy. An oblique segment is removed from the ulna, after which the distal radial-ulnar joint is freed, making sure structures stay attached to the styloid process. After this, the freed distal end is reattached to the proximal ulna with the formerly mentioned plate.

"Total DRUJ replacement"

An alternative treatment for patients with ulnar-sided wristpain is a total replacement of the distal radial-ulnar joint. There are many surgical treatments of the condition, but most of these only improve the alignment and function of the radiocarpal joint. A persistent problem in these treatments has been the stiff DRUJ. However, a prosthesis helps in managing the pain, and might also improve the range of motion of the wrist.

The procedure consists of making a hockey-stick shaped incision along the ulnar border. This incision is made between the fifth and sixth dorsal compartment. Being careful not to harm any essential structures, like the posterior interosseous nerve, the incision is continued between the extensor carpi ulnaris and the extensor digiti quinti, until the ulna is found. The ulnar head is then removed. A guide wire is then inserted in the medullary canal of the ulna, allowing centralization for a cannulated drill bit. A poly-ethylene ball, which will serve as the prosthesis, is then placed over the distal peg. After confirming full range of motion, the skin will be closed.

"Dome Osteotomy"

In case of Madelung's Deformity in conjunction with radial pain, a dome osteotomy may be conducted. For more information about this procedure, please refer to the treatment of Madelung's Deformity in children.

Around 50% of the AT/RTs will transiently respond, but chemotherapy by itself is rarely curative. No standard treatment for AT/RT is known. Various chemotherapeutic agents have been used against AT/RTs, which are also used against other CNS tumors including cisplatinum, carboplatinum, cyclophosphamide, vincristine, and etoposide. Some chemotherapy regimens are listed below:

- CCG clinical trial CCG-9921 was activated in 1993 and published its results in 2005. The proposed treatments did not have different outcomes and were not an improvement on prior treatments. Geyer published a review of chemotherapy on 299 infants with CNS tumors that evaluated response rate, event-free survival (EFS), and toxicity of two chemotherapeutic regimens for treatment of children younger than 36 months with malignant brain tumors. Patients were randomly assigned to one of two regimens of induction chemotherapy (vincristine, cisplatin, cyclophosphamide, and etoposide v vincristine, carboplatin, ifosfamide, and etoposide). Intensified induction chemotherapy resulted in a high response rate of malignant brain tumors in infants. Survival was comparable to that of previous studies, and most patients who survived did not receive radiation therapy.

- Sarcoma protocols. There has been at least one report in the literature of malignant rhabdoid tumors of the CNS being treated in as a high-grade intracranial sarcoma. These three cases were treated with surgery, chemotherapy, radiotherapy and triple intrathecal chemotherapy similar to the Intergroup Rhabdomyosarcoma Study III guidelines.

- Intrathecal protocols. One of the difficulties with brain and spinal tumors is that the blood brain barrier needs to be crossed so that the drug can get to the tumor. One mechanism to deliver the drug is through a device called an Ommaya reservoir. This is a device which shares some characteristics with a shunt in which a tube a surgically placed in the fluid surrounding the brain and a bulb shaped reservoir attached to the tubing is placed under the skin of the scalp. When the child is to receive intrathecal chemotherapy, the drug is administered into this bulb reservoir. At other times intrathecal chemotherapeutic agents are delivered through a lumbar puncture (spinal tap). A current Pediatric Brain Tumor Consortium Protocol uses intrathecal mafosfamide, a pre-activated cyclophosphamide derivative, in addition to other modalities to try to effect this tumor.

- High dose chemotherapy with stem cell rescue. This therapy uses chemotherapy at doses high enough to completely suppress the bone marrow. Prior to instituting this therapy, the child has a central line placed and stem cells are gathered. After therapy these cells are given back to the child to regrow the bone marrow. Stem cell rescue or autologous bone marrow transplantation, was initially thought to be of benefit to a wide group of patients, but has declined over the history of chemotherapy protocols.

Usually performing the Leopold maneuvers will demonstrate the presentation and possibly the position of the fetus. Ultrasound examination delivers the precise diagnosis and may indicate possible causes of a malpresentation. On vaginal examination, the leading part of the fetus becomes identifiable after the amniotic sac has been broken and the head is descending in the pelvis.

The goal of treatment in Panner disease is to relieve pain. Treatment for Panner Disease is very minimal because in most children the bones repair their blood supply and rebuild themselves and this leads to the rebuilding of the growth plate and the capitellum returns to its normal shape. The period of rebuilding and regrowth varies from child to child and can last anywhere between weeks to several months. To relieve the pain, the child is restricted from participating in sports and activities until the elbow is healed and to also rest the affected elbow. Rest will allow for the pain to be relieved and return of full elbow movement. It may also be recommended for children to apply an icepack or heat to the elbow to alleviate pain and swelling. If the child has great difficulty bending and straightening the arm then physical therapy may also be recommend. Occasionally, it is recommended for children to use nonsteroidal anti-inflammatory drugs (NSAIDs) or acetaminophen to also reduce pain and swelling. For treatment, Panner Disease heals well in children with rest and restriction of physical activity and sports using the affected arm. The prognosis is also good with treatment and the affected capitellum is remodeled. Irregularities of the capitellum and surrounding elbow area can both be seen by radiograph and MRI. When treatment is effective the flattened and fragmented capitellum is completely remodeled and returns to its normal circular shape, and also the high intensity signal on a MRI T2 series disappears. These results indicate that the capitellum is completely remodeled and the child is able to return to normal physical and sports activities.