(left hip: DDH = 33.3%, AD = 19.1%), bilaterality (DDH = 45.1%, AD = 61.2%), and breech presentation (DDH = 25.3%, AD = 9.4%). Over 50% of all the respondents had a family history of hip disease; over 40% were first-order relatives. First-order family members of patients with AD had a higher incidence of hip replacement by the age of 65 (50.0% vs. 22.7%). Patients with DDH were more likely to have first-order family members with DDH (59.0% vs. 15.8%).
CONCLUSIONS: This study confirms demographic differences between patients diagnosed with hip dysplasia in infancy versus adolescence/adulthood and supports the hypothesis that these represent distinct forms of dysplasia. In both, there is a familial tendency toward hip disease with a higher incidence of arthroplasty in the AD group's family members and higher frequency of infantile dysplasia in the DDH group's family members.
CLINICAL RELEVANCE: Infantile DDH is diagnosed with neonatal examination and patients are routinely followed into adolescence. Adolescent/adult AD is not detected until symptoms develop. Further study is needed to determine whether younger family members of patients with hip osteoarthritis should be screened to detect potentially at-risk hips.

PMID: 23389561 [PubMed - indexed for MEDLINE]

Read more... http://www.ncbi.nlm.nih.gov/pubmed/23389561?dopt=Abstract