Parvizi v. Maloney Over Direct Anterior

“There isn’t a single randomized prospective study showing that the direct anterior is worse than other approaches, ” says Jay Parvizi. “It’s the marketing, ” says Bill Maloney. “This approach is being pushed by patients because of that. And it’s harder clinically…in part because you can’t easily visualize the femur.”

This week’s Orthopaedic Crossfire® debate was part of a landmark event, the first Brazilian CCJR meeting. The event, which took place in September 2014, was held in Iguassu Falls. This week’s Orthopaedic Crossfire® debate is “The Direct Anterior Approach: Optimizes THA Outcome.” For the proposition is Javad Parvizi, M.D., F.R.C.S. from the Rothman Institute in Philadelphia, Pennsylvania. Against the proposition is William J. Maloney, III, M.D. from Stanford Hospital and Clinics in California. Moderating is Daniel J. Berry, M.D. of the Mayo Clinic.

Dr. Parvizi: “I think that the direct anterior approach optimizes outcomes. Dr. Maloney is the gladiator of orthopedics, but he will have a difficult time in terms of finding justification for continuing the way we’ve been going.”

“Direct anterior is a tougher technical approach and has to go through its learning curve. But learning curves aren’t always bad. In an abdominal aortic aneurism in the early days there were problems and if these innovators had stopped at that point then we wouldn’t be doing endovascular surgery to treat abdominal aneurism.”

“Dr. Maloney may try to argue that you need a very expensive table in order to perform a direct anterior approach. Not so. My partner and I have never performed the direct anterior approach on a special table. You do need special instruments in order to modify the surgical technique. The direct anterior approach is not the two incision total hip arthroplasty (THA) that has been abandoned by most surgeons based on great articles that came out condemning the two incision technique as not bringing much to orthopedics.”

“There are, however, numerous studies on direct anterior. There isn’t a single randomized prospective study showing that the direct anterior is worse than other approaches. In order to distill the literature I have used an analytic hierarchy process, something which evaluates the surgical approach based on numerous attributes and then providing a ‘spidergram.’ If you compare direct lateral with direct anterior, the latter wins in just about every aspect of surgery. In particular, the functional outcome of the direct anterior approach is much better than the direct lateral and the posterolateral approach. There are numerous studies showing that the direct anterior is better than direct lateral and two others that have shown that direct anterior is better than the posterolateral approach.”

“Why is it better? It leads to low bleeding, less postoperative pain, shorter length of stay (LOS), faster functional recovery, and shorter operative time (at least at Rothman Institute). So innovation in THA with the use of the direct anterior approach has brought pain control, blood conservation, and faster functional recovery. I would argue that the direct anterior approach is here to stay and it will be one of the most popular approaches in hip arthroplasty in the future. And for those of you who are standing by to see what happens, you might get hurt in the process.”

Dr. Maloney: “Jay, Jay…I was easily misled when I was your size. At the risk of introducing some science in to the discussion I’ll actually show some data.”

“There are definite disadvantages with the anterior approach. It’s difficult to visualize the femur, the femoral cutaneous nerve often gets injured, there’s radiation exposure for both patient and surgeon, leg length equalization is difficult if you use the fracture table, and the learning curve is long.”

“Steve Wilson did a study in a community hospital where they introduced the anterior approach; five surgeons compared this approach to the standard length posterior approach. They started the anterior approach mostly for marketing reasons because they were getting pressure from patients to do minimally invasive hip replacement and to reduce their dislocation rates. Four of the five surgeons went and worked with Joel Matta to figure out how to do the operation. They did it Joel’s way; they used fluoroscopy and used a fracture table.”

“This is what happens in a real world community practice…not at a high volume center where people usually do studies. They accomplished their goal, i.e., they grew their volume. One surgeon’s volume increased five times. They increased the percentage of cementless fixation and they started using larger heads—which is primarily the reason for the reduced dislocation and more hard bearings. They used more regional anesthesia and had to use more drains because they were losing more blood, and they allowed the patients to progress quicker. Their surgical time was high. Few studies show that you can do the anterior approach faster than a mini posterior approach.”

“For a standard posterior approach it was about two hours and 164 minutes for the anterior approach. Anesthesia time was longer, the LOS decreased by a day, and patients lost more blood. The high volume surgeon probably did the best in terms of decreasing LOS (4 to 2.2 days).”

“The fracture rate was high: 5% in the first 20 cases and about 3% after that. Some of these fractures were significant in terms of delaying patient rehab and affecting the long term outcome. If you examine major complications, it was 9% with anterior versus 2.6% standard posterior approach.”

“A friend of mine was at a high volume East Coast institution. This is someone who started out with trochanteric pain, had injections, had an MRI, experienced cartilage loss, and ended up with a bone scan and hip scope. The hip got worse and the X-rays deteriorated; the patient ended up with a total hip replacement through an anterior approach. The first two weeks were no problem, but then the patient had a sudden onset of thigh pain. She had a back MRI and epidurals…then an X-ray (which looked fine). The pain decreased somewhat, but then pain appeared on the opposite side. But the X-ray wasn’t fine; the implant subsided and she had a significant leg length discrepancy. She then had a left hip replaced through an anterior approach and six weeks postop on the left she had persistent groin pain and the socket has changed position.”

“They didn’t think it was the surgeon, so she got a rheumatology workup and 10 months later she has a revision socket. Later she had her right leg lengthened. She initially has an uneventful recovery, but then she starts to have pain. She gets infected on the right side and gets a head and liner exchange. Fast forward six months and she has pain on the left side and it is infected with a different organism. This is a 50 year old who should be back at work, but because the surgeon used an anterior approach she ends up having 13 operations over two years.”

“A study from Mark Pagnano at Mayo on two high volume surgeons who are way past the learning curve; same pain protocol and same rehab protocol comparing direct anterior and mini-posterior approaches. They were pretty much the same, with some slight advantages for the posterior approach in some of the categories. But basically there were insignificant differences.”

“The most important thing is getting the parts in right. The current marketing is unethical. Do what you do best.”

Moderator Berry: “In the U.S. the numbers are about 60% posterolateral, 20% direct lateral, and about 20% direct anterior. The trend is for posterior to stay pretty steady; anterolateral is going down and direct anterior is increasing. Jay, a problem with the direct anterior is that it constrains surgeons with respect to the implant you can use. Is this inherent in the direct anterior approach?”

Dr. Parvizi: “You need special instruments. As for the acetabular component you can use anything you want. You don’t need a special stem.”

Moderator Berry: “Bill, the direct anterior in the right hands seems to be doing about a well as the posterior. If you could get people to learn how to do it well could it be here to stay?”

Dr. Maloney: “It’s here to stay. The problem is that because of the websites, surgeons feel forced to do it when they’re not trained for it or comfortable with it.”

Moderator Berry: “Jay, there have been unique complications reported with the direct anterior.”

Dr. Parvizi: “Bill is right. You can get lateral femoral cutaneous nerve palsy; that happens in about 20% of my patients. Fortunately it’s always transient. Otherwise, I think that many complications happen when you’re using the table…when you lose that tactile sense. If you’re not careful and you don’t have good exposure of the femur because you haven’t done the proper exposure then you could crack the femur or malposition the femoral component.”

Moderator Berry: “Compared to a posterior approach do you think that there’s going to be a substantial, lasting difference in function with the direct anterior approach? Bill?”

Dr. Maloney: “No. Even when you look at the published papers presented at the Hip Society the posterior approach had significant early advantages over the anterior; there was little advantage to the anterior except for slightly higher Harris Hip Scores…but they were a wash after a couple of months.”

Moderator Berry: “Jay?”

Dr. Parvizi: “There are four randomized prospective studies showing that the direct anterior approach is better than the posterolateral in the early period.”

Moderator Berry: “Are those meaningful differences?”

Dr. Parvizi: “If you have a patient who wants to get back to work within a week or two, I would argue that the person should be given the chance to get back to early function. But by six weeks that might level out. And the Pagnano series…I think that’s an unfair comparison. You have a veteran of the posterolateral approach versus someone who just finished fellowship doing direct anterior approach on the table.”

Moderator Berry: “Thank you, gentlemen.”

Please visit www.CCJR.com to register for the 2015 CCJR Spring Meeting, May 17 – 20 in Las Vegas.