Screening may be key to reducing osteoarthritis later

Although some orthopaedists may view femoroacetabular impingement (FAI) as a relatively “new” condition, Rafael J. Sierra, MD, points out that published research discussed procedures similar to those currently being performed for its treatment as early as the 1930s. In recent years, the efforts of German orthopaedic surgeon Dr. Reinhold Ganz and colleagues have put FAI in the spotlight and increased understanding of this condition among the orthopaedic community.

Getting the word out
“It’s uncommon to meet an orthopaedic surgeon who does not know about FAI,” says Dr. Sierra, “because everybody talks about it. But the diagnosis is still sometimes difficult to make—especially in the hips that have very mild structural problems.”

Because awareness of FAI is not as common in the larger medical community, diagnosis is often delayed. The first person to see a teenage patient with a hip problem is often not an orthopaedist, but a family physician, an athletic trainer, or even a coach. Dr. Sierra says that his group regularly sees patients with hip problems who were originally erroneously diagnosed as having a muscle sprain or a groin pull. The key, he says, is to get primary care physicians to recognize the problem early.

“Nothing is better than early detection,” he says. “We see many patients who could have been identified earlier. I think it’s important to focus research on developing basic screening programs to detect FAI early, similar to the way we screen for scoliosis. Even though the forward-bending test [for scoliosis] produces some false positives, it identifies many patients who have significant scoliosis.”

Dr. Sierra points out that current hip scores for stratifying hip involvement don’t work as well with the young patient. One aspect of the Harris hip score, for example, is the distance a patient can walk, such as one block, two blocks, or five blocks. But young, athletic patients are capable of walking several miles or more, giving them a perfect score in that domain even though the patient experiences limitations with daily living.

Dr. Sierra has some advice for both primary care physicians and orthopaedists. The first manifestation of FAI in young patients, he says, is groin pain, usually seen with a decrease in internal rotation of the hip.

“Flex the hip to 90 degrees and internally rotate it,” he suggests. “If the patient has less than 10 degrees or 15 degrees of internal rotation, with groin pain, the patient should be referred to an orthopaedic sur­geon and an anteroposterior pelvic radiograph should be obtained.”

Dr. Sierra explains that he sees many people in their 40s with end-stage hip arthritis. He believes that if the problem had been addressed 20 years earlier, the arthritis could have possibly been prevented.

“This is only theoretical,” he admits, “because no study yet has shown that we are truly changing the natural history of the disease.”

Treatment options
Dr. Sierra explains that two treatment options for FAI exist: an open procedure and arthroscopy. Although he believes that hip arthroscopy may eventually become more commonplace, open surgery is the current standard.

“I think that hip arthroscopy is a very good option for the talented orthopaedic surgeon who can take down the rim and perform a femoroacetabular chondroplasty,” he says. “But the procedure has a very steep learning curve, and should be done only by those who can perform both the arthroscopic and open procedures equally well. Hip arthroscopy has the potential to improve a patient’s symptoms significantly, but again, it requires a very specialized surgeon.

“If the patient has major structural problems in the hip that must be corrected in addition to addressing the labral pathology,” he continues, “I think that the surgeon has to decide whether he can address all those problems arthroscopically.”

If arthroscopic repair of the labrum and rim trimming isn’t feasible, the surgeon may opt for either surgical hip dislocation (Fig. 1) or an anterior approach to the hip. Surgical hip dislocation is a major procedure that requires adequate training to prevent iatrogenic injury to the hip, including avascular necrosis. The anterior option uses either a Smith-Petersen or a Hueter approach, which enables the surgeon to visualize the anterior aspect of the femur for the chondroplasty and the acetabulum to see if rim trimming or labral repair is required.

In either case, Dr. Sierra agrees that long-term studies are needed to determine the best treatment for FAI. He knows of no published research on hip dislocation with longer than a 5-year follow-up, and the available studies on arthroscopic repair are even shorter. He suggests that the most useful approach an orthopaedist can currently take is to screen patients for FAI and address the problem early.

“Patients with advanced cartilage degeneration do not benefit from FAI surgery and may be more suitable for prosthetic replacement,” he says.

In the long run, Dr. Sierra believes that both arthroscopic management and open treatment will be part of the surgeon’s armamentarium. No matter how good arthroscopy may get, he says, surgical hip dislocation will always be needed for patients who have extensive structural problems. On the other hand, hip surgeons will need to be trained to comfortably use the arthroscope.

“Most hip surgeons have concentrated on performing total hip replacements—revisions and primaries; arthroscopy has not been part of our practice,” he says. “Most surgeons who do arthroscopy are in sports medicine. Joint replacement surgeons can learn a lot from sports medicine specialists because their rehabilitation regimens are very different from the ones used with total hip replacement. We need to train hip surgeons to perform arthroscopy well, to become very knowledgeable and skilled so that they can also do these procedures.”

Dr. Sierra reports the following disclosures: Biomet, DePuy, Zimmer, and Stryker.

Peter Pollack is a staff writer for AAOS Now. He can be reached at ppollack@aaos.org

Editor’s Note: A recent study in the Journal of the AAOS examined the issue of femoroacetabular impingement (FAI), in particular the importance of early screening for this condition. In an interview with AAOS Now, lead author Rafael J. Sierra, MD, expanded on the connection between FAI and osteoarthritis of the hip.