Etiology and Pathomechanics of Femoroacetabular Impingement
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Purpose of review
Femoroacetabular impingement is a common cause of hip pain in young patients and has been shown to progress to osteoarthritis. The purpose of this review is to better understand the development of femoroacetabular impingement.
Recent literature shows little genetic transmission of FAI. However, molecular studies show strong similarities with the cartilage in osteoarthritis. The development of cam lesions has a strong association with sports participation, particularly at the time of physeal closure suggesting abnormal development. Lumbar, pelvis, and femoral biomechanics may also play an important role in dynamic impingement.
In summary, femoroacetabular impingement is a dynamic process with many influences. Further research is needed to clarify the pathophysiology of FAI development in hopes of finding preventative options to reduce symptoms and progression to osteoarthritis.
KeywordsFemoroacetabular impingement FAI etiology FAI pathomechanics FAI pathophysiology Cam development Pincer development
Compliance with ethical standards
Conflict of interest
W. Jeffrey Grantham declares that he has no conflict of interest. Marc J. Philippon reports royalties from Smith & Nephew, Arthrosurface, Arthrex, Bledsoe, ConMed Linvatec, DonJoy, SLACK Inc., and Elsevier, consultancy fees from Smith & Nephew and MIS, and research support from Smith & Nephew, Ossur, Arthrex, and Siemens.
Human and animal rights and informed consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance
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