Researchers at the University of Utah recently reported that unsuspected hip dysplasia is common in relatives of patients who had surgery for hip dysplasia. https://www.ncbi.nlm.nih.gov/pubmed/25705807. Their study found early signs of hip dysplasia in one out of four close relatives. This included brothers, sisters, parents, grandparents, grandchildren or half-brothers and half-sisters. Most of the people with unsuspected hip dysplasia were younger than thirty, but after age thirty, many had hip pain.
This means that any family with a single person who needed surgery for hip dysplasia should be aware that the rest of the family may also have hip dysplasia. The authors of the study suggested that family members should have screening x-rays to look for hip dysplasia because early detection of hip dysplasia can have benefits, even for adults who don’t have pain. If silent hip dysplasia is detected, there are additional imaging studies that can help determine severity to make recommendations before advanced joint damage has occurred.
It’s important to keep in mind that this study only looked at relatives of patients who needed surgery. It’s possible that those patients had a more severe type of hip dysplasia that carries greater risk for other family members. So, this information can’t be applied to all families with hip dysplasia. It’s well known that hip dysplasia runs in families, but it’s too early to recommend x-rays for all family members of patients with mild dysplasia, or for family members of a child who was successfully treated without surgery.
Although genetics contributes to the risk of hip dysplasia, genetics might not be the whole story. Disorders can run in families because families share dietary and cultural habits that could increase the risk of hip dysplasia. For example, it’s known that hip dysplasia is more common in cultures that swaddle their children tightly in the traditional position with the legs straight. Hip dysplasia is also more common in Northern climates and in babies born during winter months. Finding environmental factors is important so the causes of hip dysplasia can be identified. Knowing the genetics helps identify those who should be screened. In the final analysis, there’s probably a combination of genetics and environmental causes of hip dysplasia, but that remains to be determined.
This study from the University of Utah confirms that preventive measures and early detection are especially important for families with a known history of hip dysplasia. The International Hip Dysplasia Institute is promoting and conducting research to evaluate environmental factors that might also contribute to hip dysplasia. A better understanding of genetic and environmental factors will help decrease the burden of hip dysplasia for future generations.