FEMOROACETABULAR IMPINGEMENT

Femoroacetabular impingement (FAI) is a term used to describe morphologic alterations of the proximal femur, the acetabulum, or both that result in the intra-articular damage and the early onset of secondary osteoarthritis (OA). FAI can be a result of conditions such as slipped capital femoral epiphysis (SCFE), Legg-Calvé-Perthes disease (LCPD), coxa vara, or morphological alterations such as acetabular retroversion or coxa profunda. Regardless of the etiology, the main problem is a mismatch in geometry of the proximal femur and the acetabulum that results in restricted motion and abnormal joint loads. This morphological mismatch of the femur and acetabulum, combined with the forceful activities, can lead to mechanical damage of the hip joint and the early onset of OA, as it has been observed during the open surgical treatment of FAI. 1-4.