Over the years, surgeons have used a variety of surgical approaches to perform total hip replacement. Recently, there has been renewed excitement about the anterior approach. Much of this information is provided in the form of marketing/advertisement by surgeons working hard in competitive markets to grow their practice. Patients increasingly are led to believe that the anterior approach is a "different" operation. This is simply not true. The anterior approach is simply one of many approaches that can be used to perform hip replacement. I believe the data suggest the anterior approach is more about marketing than improved results.
Total hip replacement is an excellent operation. It is very forgiving. When performed well, it is expected to provide dramatic improvement in pain, and quality of life for decades....regardless of approach.
Why are there different approaches?
Surgical approaches are anatomically safe routes between tissue planes that allow adequate exposure of deep anatomical structures. In the case of hip replacement surgery we must expose the acetabulum (hip socket) and femoral neck (top of the thigh bone). In some areas of the body there is really only one good approach. The hip, however, can be approached from the front, side, and back. Once down to bone, the operation is essentially identical, regardless of approach.
Surgery, in general, has trade-offs. We need to cause controlled trauma to improve or fix something. As long as the improvement in disease outweighs the surgical trauma, the surgical procedure is worth doing. Obviously, the lower the surgical trauma the better for the patient. No surgery can be done without some trauma to the patient. In orthopedic surgery, the more accurately we can implant the joint replacement components, the better.
With hip replacement surgery, we are replacing the patient's worn out ball and socket joint. It is crucial to place the socket (acetabular component) in a precise position. Think of the socket as a hemisphere. It is ideally aimed to be open to the side (horizontal inclination) and open to the front (anteverted). To accomplish this, the femur needs to be moved out of the way. If the cup is not ideally placed, it could allow the hip to dislocate or wear more rapidly than expected. For this reason, surgeons always look for ways to improve the position of the socket.
Good surgeons are able to safely and precisely replace hips through any approach, however, most surgeons choose an approach based on their training and experience, and use it routinely. This repetition allows for greater reproducibility in outcomes. Traditionally, it was felt that the anterior approach allowed more accurate placement of the cup, with a potentially lower dislocation rate. The trade off was a higher rate of femur fracture because the anterior approach required more twisting of the femur during surgery. Recent studies (see below) bring this traditional tradeoff into question.
I trained primarily with the posterior approach, and with a very low rate of dislocation using conventional (manual) alignment guides, I never felt the increased risk of intraoperative fracture warranted switching to the anterior approach.
Robotic Total Hip Replacement...The most accurate total hip replacement.
Now that I perform hip replacements robotically, there is absolutely no reason to consider changing approaches for accuracy. It turns out that the robotic posterior approach is the most accurate way to perform total hip replacement.
But don't patients recover faster using the anterior approach?
Most patients can bear full weight immediately and are able to go home the day after surgery with only mild pain regardless of approach. Any subtle differences, if any, patients experience between different approaches are gone within a few weeks.
Risk vs. Benefit
Two recent papers involving nearly 10,000 patients suggest there are potentially some significant disadvantages to the anterior approach relative to the posterior approach. The first paper found that hip replacements performed via the anterior approach became infected at over double the rate. The second paper found the posterior approach had a lower rate of complications and equal dislocation rate when compared to the anterior approach.
The posterior approach appears to be the most accurate, and safest way to perform total hip replacement.
Orthopedic Surgeon focused on the entire patient, not just a single joint.