What is Femoroacetabular Impingement?Femoroacetabular impingement, a pathology discovered by Swiss and German orthopaedic surgeons at the end of the 20th century, currently represents the main cause of osteoarthritis of the hip, or in other words, wear of this joint. Research has been published in scientific journals stating this to be the cause of osteoarthritis in 60 to 70% of patients who have been implanted with a total prosthesis. The characteristic feature of this pathology is impaction between the lowest part of the femoral head and the rim of the acetabulum during inward flexion-rotation movements. This produces the characteristic pain which the patient reports around the hip, especially towards the groin. Two different mechanisms are distinguished, which can appear separately or concurrently:
Pincer effectWhere the femoral head-neck junction impacts the anterosuperior wall of the acetabulum whilst producing "contrecoup" abrasion at the posteroinferior wall. The acetabulum presents overcoverage or possibly even retroversion (figures A and B). Cam effectThere is asphericity at the femoral head-neck junction in the form of hump which presses against and abrades the anterosuperior wall of the acetabulum during flexion (figures C and D). Femoroacetabular impingement is the most common cause of pain in athletes according to a recent publication by Dr. Marc Philippon in the American Journal of Sports Medicine, although it is not necessarily a pathology exclusive to athletes, e.g. after long periods sitting down while driving vehicles, sitting in an office... A study performed by Dr. Michael Leunig in the Swiss population shows that 15% of the population have hip deformities with a predisposition to suffering from femoroacetabular impingement. Whether or not they suffer from it depends on many factors, but we currently know that: We must treat patients with symptoms as early as possible, given that there is no spontaneous remission without correction. Deformities should not be treated preventatively in the absence of symptoms. Certain types of hip are more prone to suffering from femoroacetabular impingement: for example, a femoral head with a hump where the upper part of the hump impacts the acetabulum during flexion and prevents the femur from moving into the joint. This produces friction on the covering or cartilage and deteriorates it over time. The patient begins to notice that it is hard to flex and turn their leg inwards during adolescence or youth. For some, walking a lot, especially uphill, getting in and out of cars, practicing sports such as golf, running, skating, kicking, both if it is the pivoting leg or the one which is moving causes "tiredness", the feeling of "heavy hip" and even pain. It is important to have these symptoms checked, although there are few of us specialists in the world who are familiar with this pathology at present. By way of example, the man who discovered femoroacetabular impingement, Professor Reinhold Ganz, was nominated for the Nobel Prize in Medicine in 2006 for his career as a whole by the North American AO Foundation. Download presentationof femoroacetabular impingement |
