Clinical interest in femoroacetabular impingement (FAI) has intensified since 2003 after FAI was identified as a cause of hip pain in younger individuals. In FAI, the femoral head and acetabulum rub abnormally, creating damage to the articular cartilage, a mechanism that can lead to early hip arthritis. As a result of the confluence of these two trends, improving early detection and treatment of FAI is a high priority for hip specialists.
In the past, treatment focused on open procedures for restoration of the structural abnormalities around the hip and treatment of labral and cartilage pathology. Today, Mayo Clinic surgeons who specialize in young hip issues are focusing on the management of selected patients with early FAI — average age about 30 years — through less invasive approaches that include hip arthroscopy.
More than 30,000 hip arthroscopies were performed in the United States in 2008. That number is expected to increase consistently at an average annual growth rate of more than 15 percent, thus exceeding 70,000 procedures by 2013. While Mayo Clinic surgeons still use hip arthroscopy to remove loose bodies and repair traumatic labral tears, the practice is changing. Over the past three years, Mayo surgeons have also begun using arthroscopy to treat hips with FAI.
Hip arthroscopy has been performed for more than 15 years. This approach has gained renewed attention because of clinical interest in FAI and the ongoing trend toward developing less invasive treatment options. The enthusiasm for hip arthroscopy is also aided by the rapid development of hip-specific arthroscopic instrumentation.
Mayo surgeons team with sports medicine rehabilitation experts early, before FAI surgery. The team credits this early, synergistic melding of specialties — adult reconstructive surgery, arthroscopy and sports medicine physical therapy — with the procedure's high success rates.
In this team model, surgeons have the capacity to perform a full open procedure, a full arthroscopy, or a combined arthroscopy and mini-open technique, as conditions indicate. Therapists can individualize a stepwise rehabilitation program before the surgery, thus optimizing chances for immediate compliance.
Mayo Clinic orthopedic surgeons work as a team to take a well-considered approach to hip arthroscopy. To choose a technique, the team discusses all aspects of the physical examination findings, patient symptoms and radiographic criteria. They pay special attention to the main components of FAI that determine approach: labral pathology and bony abnormalities, including whether acetabular version and normal femoral head sphericity are normal.
A patient with a large structural abnormality of the hip joint is typically treated with an open technique. If there are structural abnormalities that surgeons can correct safely arthroscopically, then this approach is chosen. Safety must always guide selection of technique.
To advance care of femoroacetabular impingement (FAI), two initiatives are under way at Mayo Clinic:
It is unclear who is predisposed to FAI and when onset occurs. An FAI screening program aimed at detecting patients at risk may help answer these questions. Performed as part of a teen's pre-participation sports physical, the prototype identifies teens with hip stiffness and limitation of motion. Radiographs and magnetic resonance imaging reveal tissue and bone defects.
The screen has the potential to provide much-needed information about the natural history of FAI and to affect youths' lives by detecting potentially damaging changes in the hip early, just as did screening for scoliosis.
Randomized clinical trial
One weakness in FAI surgical decision making is the lack of comparative outcome data on arthroscopic vs. open techniques. Long-term follow-up data for open surgery are available, but only one or two years of outcome data have been published for arthroscopic procedures. Mayo is filling the data gap by designing a randomized clinical trial comparing the two techniques.