As a Fellowship Trained Joint Replacement Surgeon, I am often asked about the latest developments in arthritis surgery. With the advent of minimally invasive techniques in orthopedic surgery there has been a renewed interest in performing hip replacement through the front (anterior) of the hip as opposed to the more traditional posterior, or backside approach.
The logic behind anterior hip replacement is to try to minimize muscle damage by separating muscles to gain access to the front of the hip as opposed to releasing and repairing the muscles to gain access to the hip joint form behind. In short, there is no perfect way to deliver implants to the hip joint. If there were, we would all be performing that approach only for hip replacement surgery. Having given you this background, these are the most frequently asked questions encountered in my office:
Is anterior hip replacement a new technique?
No. The anterior hip approach was first described by Smith-Petersen in 1917. It was used by the French surgeon, Robert Judet, in 1947 to perform an isolated femoral head replacement. This later evolved into other French surgeons performing complete hip joint changes through anterior exposure in the 1960's.
If this technique has been in existence since 1960, why all the interest now?
Early surgeers found that the visualization of the hip socket was excellent through the front of the hip; although it was very difficult to insert a long straight metal stem down the femur through an anterior approach. If complications occurred during surgery it was very difficult to change or extend the anterior approach to overcome difficult surgeries and provide for better visualization. Therefore, most surgeons opted to perform hip replacement through posterior, or posterior and lateral exposures. The posterior approach has become the standard of care since that time. By using specialized instrumentation, new generation hip implants, a custom operating table, and real time intraoperative x-ray equipment, anterior hip replacement has made a resurgence. These additions have allowed the anterior approach to become easier and more reliable to perform than before.
What are the drawbacks to anterior hip replacement?
Performing an anterior total hip replacement requires positioning on a special operating table with the legs attached directly to the table. By manipulating the table, the leg is positioned to insert the hip stem. Since it is difficult to judge how much force is applied to the leg, fractures in the leg bones have occurred on the operating table. The implants are placed using real time x-ray equipment; if that equipment is malpositioned the implants can be misplaced leading to potential increased wear or dislocation and a painful joint.
Is it true that hips done through an anterior approach will not dislocate?
No. All hip replacements can dislocate. Historically, the incidence of dislocation from an anterior approach is less than through a posterior approach. However with a new generation of hip replacements, the use of larger femoral head replacements has reduced the incidence of hip dislocations for all approaches.
What hip approach do you recommend?
I recommend finding a surgeon who is versed in anterior, posterior, and anterolateral hip replacement. Since every hip exposure has specific pros and cons, it is the job of the surgeon to match each individual patient's need to the specific approach. Patients and surgeons want to minimize pain and speed recovery, yet the main objective of hip replacement is to provide patients with a well done operation, with good component position, and the expectation that it will last for the next 20-30 years.