The advantages of arthroscopy's minimally invasive approach are now being offered to more patients suffering from a wider range of hip disorders. This development requires the mastery of advanced arthroscopic techniques to fully leverage the more sensitive and effective instrumentation now available, as well as the enhanced visualization of morphological anomalies.
Innovative applications are typically seen at high-volume specialty orthopedic centers staffed to accommodate the steep learning curve of advanced arthroscopy. Bruce A. Levy, M.D., an orthopedic surgeon at Mayo Clinic in Rochester, Minn., says, "Hip arthroscopy can be very technically demanding because of the large complex of muscles crossing the joint. One key to success is development of a supportive infrastructure of surgical expertise that can rapidly adapt to new arthroscopic applications as the technology becomes available."
Colleague Rafael J. Sierra, M.D., an orthopedic surgeon, adds, "For best outcomes with advanced arthroscopic techniques in the hip, you also need to have dedicated orthopedic aftercare and rehabilitation specialists who are integral members of the team."
Another orthopedic surgeon on the advanced arthroscopic techniques team, Aaron J. Krych, M.D., attributes the expanding applications to improved understanding of the specific pathoanatomy of the hip. When combined with technical advances in surgical instrumentation, this understanding enables more areas in and around the hip to be accessed arthroscopically, such as the peritrochanteric space, the area outside the hip joint where the powerful abductor muscles are located, including the gluteus medius and minimus and the associated trochanteric bursa.
The gluteus medius is the main abductor muscle in the hip that allows a person to walk with a level pelvis. Some patients with lateral hip pain and weakness may have a gluteus medius tear. "This tendon can be accessed arthroscopically in the peritrochanteric space of the hip and can be thought of as very similar to the 'rotator cuff of the hip,' " Dr. Krych says.
In patients with internal snapping hip syndrome, a painful sensation is caused by slippage of the iliopsoas tendon as it crosses the anterior femoral head or the iliopectineal eminence. It typically occurs as the hip comes from the flexed, abducted, externally rotated position toward extension. Pain emanates from the groin and can be confused with hip joint pathology.
With advanced arthroscopic techniques, the surgeon can pass through the central compartment of the hip during arthroscopy, making a small window in the capsule to locate the tendon and release it. Dr. Levy notes, "At this level it's 50 percent muscle and 50 percent tendon, so it's more like a fractional lengthening of the muscle as opposed to a complete detachment."
Among the most recent advances in arthroscopic hip surgery is the treatment of the capsule. In the past, to access the hip joint the surgeon would cut through the capsule and often remove significant amounts of capsule. This may have contributed to instability of the hip in the form of microinstabilities.
Now, with newer techniques and instrumentation, arthroscopic surgeons usually can restore the anatomy by closing the capsule that has been cut. This minimizes the amount of capsule resected and helps stabilize the hip.
Since 2003 it has been recognized that there is a pathological relationship between femoroacetabular impingement (FAI) and the development of early osteoarthritis of the hip joint in young adults.
This patient group has an underlying structural deformity in one or both of the two parts of the hip joint, the femoral head and neck or the acetabulum. These deformities give rise to distinctive types of lesions: Pincer lesions amount to an over-coverage of the femoral head. Cam lesions are a bony protuberance that forms at the junction of the femoral head and neck.
Patients typically seek medical care due to pain from a labral tear. In the past, all FAI patients were treated with an open surgical hip dislocation to gain access. Labral tears were repaired with sutures and anchors, and the normal geometry of the hip joint and sphericity of the femoral head-neck junction were restored surgically.
These same repairs can now be made in carefully selected patients using advanced arthroscopic technique and improved instrumentation. "Our experience, and reports in the literature show that due to its minimally invasive nature, arthroscopic FAI patients tend to have less morbidity, significantly less pain and less challenging rehabilitation," Dr. Sierra says.
To further improve the evidence base of FAI management, Mayo Clinic orthopedic surgeons are developing two randomized clinical trials. One evaluates open surgery versus arthroscopic management of FAI, and the other addresses perioperative pain management with nerve blocks, as compared to absence of nerve blocks.
Mayo Clinic orthopedists also are expanding the Young Hip Clinic they began three years ago to provide the most current care to young adults with disabling hip pain. Both open and arthroscopic hip surgeons participate in surgical consultations to assure that each patient receives individual and optimal treatment based on unique needs.