If hearing loss does not occur by age 50, it is significantly less likely to occur in the years afterwards. Mixed hearing loss is most common among those with OI of all age groups, while conductive hearing loss is most likely to affect older people, with sensorineural hearing loss most likely to affect children.Although relatively rare, OI-related hearing loss can also begin in childhood; in a study of forty-five children aged four to sixteen, two were found to be affected, aged 11 and 15. In a different 2008 study, the hearing of 41 people with OI was checked. The results showed that 88% of those over 20 years of age had some form of hearing loss, while only 38% of those under 20 did.Hearing loss is most common in type I OI; it is less common in types III and IV. : 294–296  Other parts of the inner ear may also be affected by OI. causing balance issues; however, only small studies have found links between vertigo and OI. : 308  OI may worsen the outcome of medical treatments which correct hearing loss.Besides OIs association with sensorineural hearing loss, OI is associated with a number of neurological abnormalities, usually involving the central nervous system, due to deformities in the skeletal structures surrounding it. Neurological complications, especially basilar invagination, may adversely affect life expectancy. In OI, this is most often due to upwards migration of the dens,: 106–107  a feature of the C2 vertebra.
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 (Madelungs deformity). Causes
It is caused by mutations in the short-stature homeobox 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. Diagnosis
Diagnosis is made following genetic blood testing. Treatment
History
LWD was first described in 1929 by André Léri and Jean A. Weill. References


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