Arthroscopic Treatment of Femoroacetabular Impingement

Abstract not available. Introduction provided instead.

Femoroacetabular impingement (FAI) is caused by conflicts among the femoral head–neck junction, the peripheral acetabulum, and the acetabular rim. Two types of FAI have been identified: cam and pincer.¹

Cam FAI is an out-of-spherical head, caused by a bone metaplastic overgrowth at the head–neck junction, that damages the articular cartilage from overload and shear as it rotates into the socket. The result is a spectrum of degenerative changes in the labrum and in acetabular cartilage.² We have observed softening and blistering of the anterior acetabular articular cartilage in the earliest stages, to labrocartilaginous junctional degeneration and tearing or full-carpet delamination from the bone in the late stages.

Pincer FAI occurs with acetabular overcoverage, which limits range of motion (ROM) and leads to a conflict between the acetabulum and the femur. The result is more labral damage than acetabular articular changes. Ganz popularized what has become the classic treatment for FAI: open surgical dislocation and trochanteric osteotomy with removal of the offending bone at the head–neck junction,
recreating a spherical head in cam FAI.¹ Trimming of an acetabular rim osteophyte with either removal or refixation of the labrum was later described as a treatment for pincer FAI.^3,4 An arthroscopic equivalent to the open treatment has become popular as a less invasive technique with less morbidity and faster recovery.^5,6

FAI affects men and women equally, begins in the second or third decade of life, and progresses slowly. Conservative management involves avoiding activities that
aggravate the pain. In some cases, surgery may be the only alternative for relief.