Melorheostosis
Encyclopedia
Melorheostosis is a medical developmental disorder and mesenchymal
dysplasia
in which the bony cortex
widens and becomes hyperdense in a sclerotomal
distribution.
of the LEMD3 gene
. The disorder can be detected by radiograph due to thickening of bony cortex resembling "dripping candle wax". It is included on the spectrum of developmental bone dysplasias including pycnodysostosis
and osteopikolosis. The disorder tends to be unilateral and monoostotic, with only one limb typically involved. Cases with involvement of multiple limbs, ribs, and bones in the spine have also been reported. There are no reported cases of involvement of skull or facial bones. Melorheostosis can be associated with pain, physical deformity, skin and circulation problems, contractures, and functional limitation. It is also associated with a benign inner ear
dysplasia
known as osteosclerosis
.
It is not known if LEMD3 mutations can cause isolated melorheostosis in the absence of Buschke-Ollendorff syndrome
.
and regional anesthetics have been ineffective.
contestant Matt Hoffman falsely claimed that his wife suffered from the condition in order to gain sympathy from his fellow house guests.
Mesenchyme
Mesenchyme, or mesenchymal connective tissue, is a type of undifferentiated loose connective tissue that is derived mostly from mesoderm, although some are derived from other germ layers; e.g. some mesenchyme is derived from neural crest cells and thus originates from the ectoderm...
dysplasia
Dysplasia
Dysplasia , is a term used in pathology to refer to an abnormality of development. This generally consists of an expansion of immature cells, with a corresponding decrease in the number and location of mature cells. Dysplasia is often indicative of an early neoplastic process...
in which the bony cortex
Cortex
Cortex may refer to:-Sciences:* Cortex , the outer portion of the stem or root of a plant...
widens and becomes hyperdense in a sclerotomal
Sclerotome
A sclerotome is part of a somite, a structure in vertebrate embryonic development. Sclerotomes eventually differentiate into the vertebrae and most of the skull...
distribution.
Diagnosis
Melorheostosis is thought to be caused by a mutationMutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...
of the LEMD3 gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
. The disorder can be detected by radiograph due to thickening of bony cortex resembling "dripping candle wax". It is included on the spectrum of developmental bone dysplasias including pycnodysostosis
Pycnodysostosis
Pycnodysostosis from , dys , and ostosis , is a lysosomal storage disease of the bone caused by a mutation in the gene that codes the enzyme cathepsin K.-Genetics:...
and osteopikolosis. The disorder tends to be unilateral and monoostotic, with only one limb typically involved. Cases with involvement of multiple limbs, ribs, and bones in the spine have also been reported. There are no reported cases of involvement of skull or facial bones. Melorheostosis can be associated with pain, physical deformity, skin and circulation problems, contractures, and functional limitation. It is also associated with a benign inner ear
Inner ear
The inner ear is the innermost part of the vertebrate ear. In mammals, it consists of the bony labyrinth, a hollow cavity in the temporal bone of the skull with a system of passages comprising two main functional parts:...
dysplasia
Dysplasia
Dysplasia , is a term used in pathology to refer to an abnormality of development. This generally consists of an expansion of immature cells, with a corresponding decrease in the number and location of mature cells. Dysplasia is often indicative of an early neoplastic process...
known as osteosclerosis
Osteosclerosis
Osteosclerosis, an elevation in bone density, is normally detected on an X-ray as an area of whiteness, and is where the bone density has significantly increased...
.
It is not known if LEMD3 mutations can cause isolated melorheostosis in the absence of Buschke-Ollendorff syndrome
Buschke-Ollendorff syndrome
Buschke–Ollendorff syndrome, also known as Dermatofibrosis lenticularis disseminata, is a rare genetic disorder associated with LEMD3. It is believed to be inherited in an autosomal dominant manner....
.
Treatment
The disorder is progressive, with the ultimate severity of symptoms often depending on age of onset. In severe cases amputation has been performed when conservative measures such as physical therapyPhysical therapy
Physical therapy , often abbreviated PT, is a health care profession. Physical therapy is concerned with identifying and maximizing quality of life and movement potential within the spheres of promotion, prevention, diagnosis, treatment/intervention,and rehabilitation...
and regional anesthetics have been ineffective.
Melorheostosis in the media
Melorheostosis gained greater recognition in 2010 when Big Brother 12Big Brother 12 (U.S.)
Big Brother 12 is the 12th season of the American reality television series Big Brother. The HouseGuests moved into the Big Brother House on July 3, 2010 and the season premiered on July 8, 2010. The show was broadcast on CBS and Showtime 2 for 75 days, concluding on September 15, 2010 when Hayden...
contestant Matt Hoffman falsely claimed that his wife suffered from the condition in order to gain sympathy from his fellow house guests.