The question is whether you should use it and I would give you maybe not because there is no free lunch. Everything has downsides.
What are the downsides? First is wound healing. In the cases that we’ve published we’ve documented a 1.9% reoperation rate mostly due to the BMI [body mass index]. There is a dose response curve to their BMI and diabetes has a very significant effect as well.
The other issue is fracture. Very real. We had 13 fractures in 1,000 patients. This is double our posterior approach cohort. And what we found was that 9 of them were over 70 years, under 25 BMI, females. So, we’ve changed our practice and in that age cohort, we only use cemented femoral stems. We eliminated this issue.
The learning curve is real. But the issue is not approach, it is newness and unfamiliarity. The better and more consistent you are with your clinical results, the less benefit you will have to change.
Dr. Springer: First I must state that I really have no problem with the anterior surgical approach. I think if we want to say it’s different, then fine, let’s say it’s different. I think what most people and surgeons have a problem with is the sensationalism and the overzealous promotion of this approach. And I would argue that emerging evidence would suggest that this is a high risk, no reward operation.
So, what are the benefits and concerns? Resource utilization, dislocation risk, better function…is it safe? I for one am certainly waiting to be overwhelmed by the literature.
Resource utilization… my operating room during a posterior approach…myself, my PA, my scrub tech…it’s one of the most relaxing operations I do.
Every time I walk by my partner’s operating room, it looks like they were in there separating Siamese twins or something like that much less doing a hip replacement.
And then we have the issues with the X-ray and the table. In our place, fluoro is billed out in one-hour increments, so even if you use it for one minute, it’s a $1,000 charge. Now, I will say I’ve found these tables to be very comfortable between cases for taking a nap and stretching out my tight hamstrings.
What about evidence for better stability? The initial data suggested higher rates of instability with the direct anterior approach, probably somewhat relative to the learning curve. The three prospective randomized studies (Taunton et al. and Barrett et al.) don’t show any difference. The registry data published in the Journal of Arthroplasty this year—out of Michigan (Maratt, et al., 2016)—no difference in dislocation rates. Both approaches less than a half a percent.
What about better functional recovery? Well, I think most people got excited about some of the initial data that came out comparing this to an anterior lateral approach where you take down a third of the abductors. Even in those studies there was no benefit functionally beyond six weeks in those patients.
What about versus the posterior approach? A meta-analysis—17 studies, 2,300 patients (Higgins, et al., 2014)—conclusions: current evidence comparing outcomes following anterior versus posterior total hip does not demonstrate clear superiority of one approach over the other.
And let’s look closely at thes prospective randomized studies, because if you just read the abstracts, you’ll be swooned. If you read the articles, you’ll be more reserved.
Bill Barrett’s study—walks further on day one and day two; did the direct anterior; less pain but took the same amount of pain medicines; stayed three-quarters of a day less in the hospital; and sub-function scores of their HOOS and HSS scores were better at six weeks as Jose demonstrated. No difference in any parameter at three months, and yet they had longer operative times; more blood loss; longer incision; and worse cup inclination—when using fluoro.
