Osteogenesis imperfecta

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Osteogenesis imperfecta
Classifications and external resources
ICD-10 Q78.0
ICD-9 756.51
DiseasesDB 9342
MedlinePlus 001573
eMedicine ped/1674 

Osteogenesis imperfecta is a group of genetic bone disorders. It is one of the brittle bone diseases. People with OI either have less collagen than normal or the quality is poorer than normal. As collagen is an important protein in bone structure, this impairment causes those with the condition to have weak or fragile bones.[21]

As a genetic disorder, OI is an autosomal dominant defect. Most people with OI receive it from a parent but it can also be an individual (de novo or "sporadic") mutation.

Contents

[edit] Types

There are six types of OI, though the symptoms range from person to person. Type I is the most common and mildest form, followed by Type II, Type III and Type IV. Types V and VI have been more recently classified, and they share the same clinical features of IV, but each have unique histologic findings.

[edit] Type I

Collagen is of normal quality but is produced in insufficient quantities:

  • Bones fracture easily, especially before puberty
  • Slight spinal curvature
  • Loose joints
  • Poor muscle tone
  • Discolouration of the sclera (whites of the eyes), usually giving them a blue-gray color
  • Early loss of hearing
  • Protrusion of the eyes, 'bug eyed'

IA and IB are distinguished by the absence/presence of dentinogenesis imperfecta (characterized by opalescent teeth.) (Absent in IA, present in IB.)

[edit] Type II

Collagen is not of a sufficient quality or quantity

Type II can be further subclassified into groups A, B, C, which are distinguished by radiographic evaluation of the long bones and ribs. Type IIA demonstrates broad and short long bones with broad and beaded ribs. Type IIB demonstrates broad and short long bones with thin ribs that have little or no beading. Type IIC demonstrates thin and longer long bones with thin and beaded ribs.

[edit] Type III

Collagen quantity is sufficient but is not of a high enough quality

  • Bones fracture easily, sometimes even before birth
  • Bone deformity, often severe
  • Respiratory problems possible
  • Short stature, spinal curvature and barrel-shaped rib cage
  • Loose joints
  • Poor muscle tone in arms and legs
  • Discolouration of the sclera (whites of the eyes)
  • Early loss of hearing

Type III is distinguished amongst the other classifications as being the "Progressive Deforming" type, wherein a neonate presents with mild symptoms at birth and develops the aforementioned symptoms throughout life. Lifespan may be normal, albeit with severe physical handicapping.

[edit] Type IV

Collagen quantity is sufficient but is not of a high enough quality

  • Bones fracture easily, especially before puberty
  • Short stature, spinal curvature and barrel-shaped rib cage
  • Bone deformity is mild to moderate
  • Discolouration of the sclera (whites of the eyes)
  • Early loss of hearing

Similar to Type I, Type IV can be further subclassified into types IVA and IVB characterized by absence (IVA) or presence (IVB) of dentinogenesis imperfecta.

[edit] Type V

Same clinical features as Type IV. Distinguished histologically by "mesh-like" bone appearance. Further characterized by the "V Triad" consisting of a) radio-opaque band adjacent to growth plates, b) hypertrophic calluses at fracture sites, and c) calcification of the radio-ulnar interosseous membrane.

  • As per Drs. Francis Glorieux and Frank Rauch and Leanne Ward in the Shriners Hospital for Children in Quebec

OI Type V leads to calcification of the membrane between the two forearm bones, making it difficult to turn the wrist. Another symptom is abnormally large amounts of repair tissue (hyperplasic callus) at the site of fractures. At the present time, the cause for Type V is unknown, though the doctors have determined that it is inherited.

X-Ray OI Type V in Adult X-Ray OI Type V Kid

More on Type V Research More on OI Study

[edit] Type VI

  • No OMIM available. - Type VI

Same clinical features as Type IV. Distinguished histologically by "fish-scale" bone appearance.

[edit] Treatment

At present there is no cure for OI. Treatments are aimed at increasing overall bone strength to prevent fracture and maintain mobility.

[edit] Physiotherapy

Physiotherapy used to strengthen muscles and improve motility in a gentle manner, while minimizing the risk of fracture. This often involves hydrotherapy and the use of support cushions to improve posture. Individuals are encouraged to change positions regularly throughout the day in order to balance the muscles which are being used and the bones which are under pressure.

Children often develop a fear of trying new ways of moving due to movement being associated with pain. This can make physiotherapy difficult to administer to young children.

At the present moment, there is no cure for O.I. however; there is a treatment option of an intravenous known as Aredia. This option is to strengthen the bones and to reduce the fracture rate of the individual. Aredia causes sickness in the induvidual at the first treatment sessions, usually is taken every 3 to 6 months

[edit] Physical aids

With adaptive equipment such as crutches, splints, grabbing arms, and/or modifications to the home many individuals with OI can obtain a significant degree of autonomy.

[edit] Bisphosphonates

Bisphosphonates (BPs), particularly the nitrogen-containing bisphosphonates, are being increasingly administered to increase bone mass and reduce the incidence of fracture. BPs can be dosed orally (e.g. alendronate) or by intravenous injection/infusion (e.g. pamidronate, zoledronic acid).

BP therapy is being used increasingly for the treatment of OI. It has proven efficancy in reducing fracture rates in children (DiMeglio, 2006), however only a trend towards decreased fracture was seen in a small randomized study in adults (Chevrel, 2006). While decreasing fracture rates, there is some concern that prolonged BP treatment may delay the healing of OI fractures, although this has not been conclusively demonstrated.

[edit] Surgery

Metal rods can be surgically inserted along the long bones to improve strength however this can have the side effect of reduced joint mobility, though not always. Spinal fusion can be performed to correct scoliosis although the inherent bone fragility makes this operation more complex in OI patients. Surgery for basilar impressions can be carried out if pressure being exerted on the spinal cord and brain stem is causing neurological problems.

[edit] Bone infections

Infections are treated as and when they occur with the appropriate antibiotics and antiseptics.

[edit] History and alternative names

The condition, or types of it, have had various other names over the years and in different nations. Among some of the most common alternatives are Ekman-Lobstein syndrome, Vrolik syndrome, and the colloquial glass-bone disease. The name "Osteogenesis Imperfecta" dates to at least 1895 and has been the usual medical term in the twentieth century to present. The current four type system began with Sillence in 1979.[1]. An older system deemed less severe types "Osteogenesis Imperfecta Tarda" while more severe forms were deemed "Osteogenesis Imperfecta Congenita."[2] As this did not differentiate well, and all forms are congenital, this has since fallen out of favour.

The condition has been found in an Ancient Egyptian mummy from 1000 BC. The earliest studies of it began in 1788 with the Swede Olof Jakob Ekman. He described the condition in his doctoral thesis and mentioned cases of it going back to 1678. In 1831 Edmund Axmann described it in himself and two brothers. Johann Friedrich Georg Christian Martin Lobstein dealt with it in adults in 1833. Willem Vrolik did work on the condition in the 1850s. The idea that the adult and newborn forms were the same came in 1897 with Martin Benno Schmidt.[3]

Frequency is approximately the same across groups, but for unknown reasons the Shona and Ndebele of Zimbabwe seem to have a higher proportion of Type III to Type I than other groups would.[4]. Although a similar pattern was found in segments of the Nigerian and South African population. In these varied cases the total number of OIs of all four types was roughly the same as any other ethnicity.

[edit] Noted people with osteogenesis imperfecta

[edit] Historical figures whose OI status is disputed

[edit] Portrayal in popular culture

Figures in film and television depicted as being afflicted with osteogenesis imperfecta include:

  • The aptly-named nicknamed Mr. Glass (so called because of the brittleness of his bones) is a major character in the movie Unbreakable . The character's real name is Elijah Price played by Samuel L. Jackson.
  • Raymond Dufayel (sometimes simply called "the glass man" by his neighbors) in the French film Amélie; Dufayel is depicted as being confined to his house (the interior of which is heavily padded) by the condition.
  • An anonymous child featured in a subplot of the ER episode Point of Origin also had a subplot involving a child with the condition.[18]
  • The movie Fragile features a child with this condition.

[edit] References

[edit] Print sources

  • The Official Patient's Sourcebook on Osteogenesis Imperfecta: A Revised and Updated Directory for the Internet Age (Icon Health Publications) ISBN 0-597-83399-0
  • Managing Osteogenesis Imperfecta: A Medical Manual (OIF publisher) edited by Wacaster Pricisalla M.D. ISBN 0-9642189-3-3
  • Third International Conference on Osteogenesis Imperfecta (Annals of the New York Academy of Sciences, Vol 543) ISBN 0-89766-482-5
  • K. Buday, Beiträge zur Lehre von der Osteogenesis imperfecta (1895)
  • Holcomb, D. Y. A Fragile-boned family: Hereditary fragilitas ossium (Journal series of the University of Arkansas) ASIN B0008CY9YS
  • Clinical Orthopaedics and Related Research Number 159 Osteogenesis Imperfecta (Published:J. B. Lippincott, 1981)
  • DO Sillence, A Senn and DM Danks, Genetic heterogeneity in osteogenesis imperfecta (1979 paper linked to current typology system)
  • Glorieux, NJ Bishop, H Plotkin, G Chabot, G. Cyclic administration of pamidronate in children with severe osteogenesis imperfecta (FH … - 1998 - biblioteca.osteogenesis.info)
  • DO Sillence Osteogenesis imperfecta: an expanding panorama of variants- Clin Orthop Rel Res, 1981. PMID 82026194
  • Glorieux FH, Rauch F, Plotkin H, Ward L, Travers R, Roughley P, Lalic L, Glorieux DF, Fassier F, Bishop NJ. Type V osteogenesis imperfecta: a new form of brittle bone disease. PMID 20431497
  • Rauch F, Glorieux FH (2004). "Osteogenesis imperfecta". Lancet 363 (9418): 1377-85. PMID 15110498.
  • Hall CM. International Nosology and Classification of Constitutional Disorders of Bone (2001). American Journal of Medical Genetics 113:65-77 (2002). PMID: 12400068
  • Cassidy SB, Allanson JE. Management of Genetic Syndromes, Second Edition. Wiley-Liss 2005. ISBN 0-471-30870-6
  • Chevrel G, Schott AM, Fontanges E, Charrin JE, Lina-Granade G, Duboeuf F, Garnero P, Arlot M, Raynal C, Meunier PJ. Effects of oral alendronate on BMD in adult patients with osteogenesis imperfecta: a 3-year randomized placebo-controlled trial. 2006 PMID 16418786
  • DiMeglio LA, Peacock M. Two-year clinical trial of oral alendronate versus intravenous pamidronate in children with osteogenesis imperfecta. 2006 PMID 16355282

[edit] Web sources

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[edit] External links

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