REVIEW ARTICLE Etiology of Femoroacetabular Impingement in Athletes: A Review of Recent Findings

The Author(s) 2015. This article is published with open access at Springerlink.com Abstract The relationship between hip deformities and osteoarthritis has recently received a lot of attention. In particular, it has been shown that both osteoarthritis and its precursors, such as the hip deformities that lead to femoroacetabular impingement (FAI), are more prevalent in elite athletes compared with the general population. However, the etiology of the above-mentioned types of hip deformity is not currently well understood. Many recent studies have attempted to shed light on the etiology of this disease. In this article, the main clinical, radiological, mechanobiological, and biomechanical findings of rele-vance to understanding the etiology of hip deformities leading to FAI are reviewed. Based on these findings, a consistent biomechanical theory explaining the develop-ment of hip deformities in athletes is then presented. Ac-cording to the presented theory, the repetitive, impact-like musculoskeletal loads that athletes experience, particularly when they undertake extreme ranges of hip motion, cause the development of hip deformities. According to this theory, these musculoskeletal loads trigger abnormal growth patterns during the years of skeletal development and cause the formation of hip deformities. A number of hypotheses based on the proposed theory are then formu-lated that could be tested in future studies to ascertain whether the proposed theory could sufficiently describe the development of hip deformities in athletes. Key Points The prevalence of cam-type deformity is higher within athletes compared with control groups. Some of the data available in the literature suggest that the repetitive high-magnitude loads experienced by the athlete during years of skeletal development may contribute to the development of cam-type deformity.