Life expectancy for individuals with hypochondroplasia is normal; the maximum height is about 147 cm or 4.8 ft.

A recent article in 2015 reported a persistent notochord in a fetus at 23 weeks of gestation. The fetus had an abnormal spine, shortened long bones and a left clubfoot. After running postmortem tests and ultrasound, the researchers believed that the fetus suffered from hypochondrogenesis. Hypochondrogenesis is caused when type II collagen is abnormally formed due to a mutation in the COL2A1 gene. Normally, the cartilaginous notochord develops into the bony vertebrae in a human body. The COL2A1 gene results in malformed type II collagen, which is essential in the transition from collagen to bone. This is the first time that researchers found a persistent notochord in a human body due to a COL2A1 mutation.

After the first discovery and description of Marshall–Smith syndrome in 1971, research to this rare syndrome has been carried out.

- Adam, M., Hennekam, R.C.M., Butler, M.G., Raf, M., Keppen, L., Bull, M., Clericuzio, C., Burke, L., Guttacher, A., Ormond, K., & Hoyme, H.E. (2002). Marshall–Smith syndrome: An osteochondrodysplasia with connective tissue abnormalities. 23rd Annual David W. Smith Workshop on Malformations and Morphogenesis, August 7, Clemson, SC.

- Adam MP, Hennekam RC, Keppen LD, Bull MJ, Clericuzio CL, Burke LW, Guttmacher AE, Ormond KE and Hoyme HE: Marshall-Smith Syndrome: Natural history and evidence of an osteochondrodysplasia with connective tissue abnormalities. American Journal of Medical Genetics 137A:117–124, 2005.

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- Butler, M.G. (2003). Marshall–Smith syndrome. In: The NORD Guide to Rare Disorders. (pp219–220) Lippincott, Williams & Wilkins, Philadelphia, PA.

- Charon A, Gillerot T, Van Maldergem L, Van Schaftingen MH, de Bont B, Koulischer L. The Marshall–Smith syndrome. Eur J Pediatr 1990; 150: 54-5.

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- Diab, M., Raff, M., Gunther, D.F. (2002). Osseous fragility in Marshall–Smith syndrome. Clinical Report: Osseous fragility in Marshall-Smith syndrome

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- Hoyme HE and Bull MJ: The Marshall-Smith Syndrome: Natural history beyond infancy. Western Society for Pediatric Research, Carmel, California, February, 1987. Clin Res 35:68A, 1987.

- Hoyme HE and Bull MJ: The Marshall-Smith Syndrome: Natural history beyond infancy. David W. Smith Morphogenesis and Malformations Workshop. Greenville, SC, August, 1987. Proceedings of the Greenwood Genetics Center 7:152, 1988.

- Hoyme HE, Byers PH, Guttmacher AE: Marshall–Smith syndrome: Further evidence of an osteochondrodysplasia in long-term survivors. David W. Smith Morphogenesis and Malformations Workshop, Winston-Salem, NC, August, 1992. Proceedings of the Greenwood Genetic Center 12:70, 1993.

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There is no known cure. In selected patients orthopaedic surgery may be helpful to try to gain some functionality of severely impaired joints.

There is no known cure for Winchester syndrome; however, there are many therapies that can aid in the treatment of symptoms. Such treatments can include medications: anti-inflammatories, muscle relaxants, and antibiotics. Many individuals will require physical therapy to promote movement and use of the limbs affected by the syndrome. Genetic counseling is typically prescribed for families to help aid in the understanding of the disease. There are a few clinical trials available to participate in. The prognosis for patients diagnosed with Winchester syndrome is positive. It has been reported that several affected individuals have lived to middle age; however,the disease is progressive and mobility will become limited towards the end of life. Eventually, the contractures will remain even with medical intervention, such as surgery.

Like treatment options, the prognosis is dependent on the severity of the symptoms. Despite the various symptoms and limitations, most individuals have normal intelligence and can lead a normal life.

Most reported cases of DEH in the literature have been treated surgically, with excision of the mass, as well as by the correction

of any deformity, while preserving the integrity of the affected joint as much as possible.

In regards to treatment of hypochondroplasia usually takes the form of orthopedic surgery and physical therapy. Genetic counseling is advised for individuals and their families. Specifically in the case of spinal stenosis, one option is laminectomy.

While Larsen syndrome can be lethal if untreated, the prognosis is relatively good if individuals are treated with orthopedic surgery, physical therapy, and other procedures used to treat the symptoms linked with Larsen syndrome.

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.

In 2005, a patient with Winchester syndrome was shown to have mutations in the matrix metalloproteinase 2 ("MMP2") gene. A 2006 study showed other mutations found in the MMP2 gene. This has led to the belief that there are many similar diseases within this family of mutations. As of 2007, it was found that these mutations are also found in Torg and Nodulosis-arthropathy-osteolysis syndrome (NAO). This means that Torg, NAO, and Winchester syndrome are allelic disorders. In 2014, a new case of Winchester syndrome was reported. According to a recently published article, it was discovered that multicentric osteolysis, nodulosis, and arthropathy (MONA) and Winchester syndrome are different diseases. Mutations in MMPS and MT1-MMP result in similar but distinctly different "vanishing bone" syndromes.

Some people may have some mental slowness, but children with this condition often have good social skills. Some males may have problems with fertility.

Langer mesomelic dysplasia (LMD) is a rare congenital disorder characterized by an altered bone formation that causes a severe short and disproportionate stature.

Treatment for Larsen syndrome varies according to the symptoms of the individual. Orthopedic surgery can be performed to correct the serious joint defects associated with Larsen syndrome. Reconstructive surgery can be used to treat the facial abnormalities. Cervical kyphosis can be very dangerous to an individual because it can cause the vertebrae to disturb the spinal cord. Posterior cervical arthrodesis has been performed on patients with cervical kyphosis, and the results have been successful Propranolol has been used to treat some of the cardiac defects associated with Marfan's syndrome, so the drug also has been suggested to treat cardiac defects associated with Larsen syndrome.

Marshall–Smith syndrome is not to be confused with:

- Marshall syndrome (aka.Periodic fever, aphthous stomatitis, pharyngitis and adenitis (PFAPA syndrome, see also: Periodic fever syndrome)

- Sotos (like) syndrome

- Weaver-Smith syndrome (WSS)

Treatments are usually based on the individuals symptoms that are displayed. The seizures are controlled with anticonvulsant medication. For the behavior problems, the doctors proscribe to a few medications and behavioral modification routines that involve therapists and other types of therapy. Even if mental retardation is severe, it does not seem to shorten the lifespan of the patient or to get worse with age.

SHORT syndrome is a medical condition in which affected individuals have multiple birth defects in different organ systems.

It was characterized in 1975.

Stratton parker syndrome is a rare disorder characterized by short stature, wormian bones (extra cranial bones), and dextrocardia (displaced heart). Other symptoms include dermatoglyphics, tooth deformities or missing teeth, abnormal kidney development, shortened limbs, mental retardation, undescended testes or cryptorchidism, and anal atresia. The condition was first described by Stratton and Parker in 1989, and there have been only four reported cases worldwide. Two cases of the syndrome were reported by Gilles-Eric Seralini in 2010 after having been contacted in January 2009.

Alternative names include "Growth Hormone Deficiency with Wormian Bones, Cardiac Anomaly, and Brachycamptodactyly" and "Short stature wormian bones dextrocardia"

Corneodermatosseous syndrome (also known as "CDO syndrome") is an autosomal dominant condition with onset in infancy, characterized by corneal dystrophy, photophobia, diffuse palmoplantar keratoderma, distal onycholysis, skeletal abnormalities, with brachydactyly, short stature, and medullary narrowing of digits.

There is no treatment at this time to promote bone growth in chondrodystrophy patients. Certain types of growth hormone seem to increase the rate of growth during the first year of life/treatment, but have no substantial effect in adult patients. Only a few surgical centers in the world perform, experimentally, leg and arm lengthening procedures. Most common therapies are found in seeking help from: family physicians, pediatrics, internists, endocrinologists, geneticists, orthopedists and neurologists.

Katz Syndrome is a rare congenital disorder, presenting as a polymalformative syndrome characterized by enlarged viscera, hepatomegaly, diabetes, and skeletal anomalies that result in a short stature, cranial hyperostosis, and typical facial features. It is probably a variant of the autosomal recessive type of Craniometaphyseal Dysplasia.

It is caused by mutations in the SHOX gene found in the pseudoautosomal region PAR1 of the X and Y chromosomes, at band Xp22.33 or Yp11.32.

SHOX gene deletions have been identified as the major cause of Leri–Weill syndrome.

Leri–Weill dyschondrosteosis is characterized by mesomelic short stature, with bowing of the radius more so than the ulna in the forearms and bowing of the tibia while sparing the fibula.

Léri–Weill dyschondrosteosis or LWD is a rare pseudoautosomal dominant genetic disorder which results in dwarfism with short forearms and legs (mesomelic dwarfism) and a bayonet-like deformity of the forearms (Madelung's deformity).

Acromicric dysplasia is an extremely rare inherited disorder characterized by abnormally short hands and feet, growth retardation and delayed bone maturation leading to short stature. Most cases have occurred randomly for no apparent reason (sporadically). However, autosomal dominant inheritance has not been ruled out.

According to the disease database, Acromicric dysplasia is synonymous with Geleophysic dysplasia

(or Geleophysic Dwarfism) and Focal mucopolysaccharidosis.

Ischiopatellar dysplasia is sometimes referred to as Scott-Taor syndrome after the researchers who first described ischiopatellar dysplasia as they recognized it in a family as an autosomal dominant disorder in 1979. This finding was important as they were the first to note that it was a benign disorder that is separate from the more severe nail-patella syndrome. Other common names for ischiopatellar syndrome are small patella syndrome (SPS), since the patellae are often small or absent in patients who have this syndrome, and coxo-podo-patellaire syndrome.