Researchers have linked Perthes' disease with several congenital conditions, pointing to intra-uterine factors behind the development of the disease.
Writing in the British edition of the Journal of Bone and Joint Surgery, the team recommends that future etiologic Perthes' disease research should be "focused on the 'fetal environment', as increasing evidence suggests an environmental factor acting early in development, and possibly in utero."
Using data from the UK General Practice Research database, the team found that children with Perthes' disease were significantly more likely to have congenital anomalies affecting the genitourinary and inguinal regions.
In particular, the 619 patients with Perthes' disease were 4.04 times more likely to have hypospadias, 1.83 times more likely have an undescended testes, and 1.79 times more likely to have an inguinal hernia than 2544 age-, gender-, and time period-matched controls without juvenile hip osteonecrosis.
As hypospadias, undescended testes, and inguinal hernia are known to be mutually associated, the researchers comment that finding an association between Perthes' disease and all three conditions "offers reassurance that this observation is genuine."
"A major hypothesis for the mechanism of these three disorders relates to altered fetal androgen metabolism, which may therefore be influential in the development of Perthes' disease and possibly explain the strong male preponderance," comment Dan Perry (Alder Hey Children's Hospital, Liverpool, UK) and co-authors.
The team also found that children who had developmental hip dysplasia were 5.13 times more likely to develop Perthes' disease than those without the condition, but says that further research is required to determine whether this association is true or due to misclassification of avascular necrosis associated with developmental hip dysplasia.
In addition, Perthes' disease was associated with generalized behavioral disorder (odds ratio [OR]=1.55), supporting previous reports of a connection, although not specifically attention deficit hyperactivity disorder.
Finally, patients with asthma were significantly more likely than those without to have Perthes' disease (OR=1.44), even after adjusting for use of oral or parenteral steroids.
"Given the increasing evidence of an association between secondary tobacco smoke inhalation and Perthes' disease this observation is of interest," Perry et al comment.
Licensed from medwireNews with permission from Springer Healthcare Ltd. ©Springer Healthcare Ltd. All rights reserved. Neither of these parties endorse or recommend any commercial products, services, or equipment.