In a systematic review of 64 studies by 2 examiners, the conclusion was that there was strong evidence for faster post-op recovery and less need for assistive devices when going anteriorly (den Hertog, et al., Hip International, 2016).
What I tell patients is that, when compared to the posterior approach, the anterior approach yields either equivalent or slightly better pain scores and slightly improved short-term functional recovery. I really emphasize to the patient that the approach is not the most important thing. The most important thing is doing the surgery correctly, so I make sure the patients understand that.
What about cost advantages? Is it cheaper? In a 2016 prospective study which looked at anterior, posterior and lateral approaches, the anterior approach in-hospital costs were about $1,000 less per patient (Petis, et al., JOA, 2016).
Another study looked at Medicare claims data from 2012-2014; 1,800 patients were matched. The anterior approach patients had lower length of stay, higher percentage of discharge to home; and lower post-acute payments by 50% compared to the control (Kamath, et al., J Med Econ, 2018).
In this era of value, I think this can be quite compelling.
In summary, the anterior approach is becoming the approach of choice for total hip arthroplasty in the United States. I believe it results in lower pain and faster functional recovery. I think there is a lower dislocation rate, although you could debate that with some of the available data. I think there’s a shorter length of stay and the reduced utilization of services makes this more cost effective. About 1/3 of my patients currently are doing this on an outpatient basis.
Dr. Meneghini: The title of my talk is Direct Anterior Approach: A Grim Future in the Modern Healthcare Environment.
Is the direct anterior approach clinically better?
Probably the best study to date was done at the Mayo Clinic. Won the John Charnley Award. It showed that the direct anterior approach has marginally faster recovery at a mean of about 5 days. (Taunton, et al., CORR, 2018) I think we know that is pretty good data. No studies to date have been able to avoid the inherent bias of patients exposed to the internet and marketing when they come to the practice.
And now we have consistent reports of complications unique to the approach, both from single center, multi-center and registry studies.
Choose your complication. Posterior approach, the Achilles heel is instability. The direct anterior approach, femoral loosening and potentially femoral fracture, depending on some factors.
By the way, the direct anterior approach has also been shown to have increased wound complications in obese patients. A 13% anterior pain associated with iliopsoas impingement (Rodriquez, et al., Orthopaedic Proceedings, 2018). An 11% anterior parathesias and pain that persisted out to 6-8 years (Patton, et al., JOA, 2018). Femoral nerve palsy, which is a devasting complication, as we all know. And it’s 14x the incidence of a posterior approach surgeon (Fleischman, et al., JOA, 2018). And we know, as Bill alluded to, increased blood loss, operative time and complications during the learning curve if you happen to be on one of those.
There is no doubt that the marketing for direct anterior approach is way better. Patients are seeking it. Hospitals are seeking it. Fellowship applicants are demanding it (Shofoluwe, et al., JOA, 2018). No doubt that it wins in that day after day.
But is the direct anterior approach more efficient? There are numerous high-quality studies that demonstrate either equal or longer operative time compared to the posterior approach.
Resource consumption—you have to have a special table. Maybe you don’t have to, but most people do. You have to have staff to run the table. And at our institution, they do not let the industry reps touch the table because of liability issues, so that requires more staff. You have fluoroscopy, which requires more time and additional software and then staff to run the fluoroscopic machine.
Dr. Meneghini seems to have made his reputation by reporting the bad results of the anterior approach. He touts his use of the posterior approach but does not report his results regarding alignment, leg length and dislocation. He does not mention use of an alternative approach for cases of spasticity(cerebral palsy etc.)where a posterior approach is contra-indicated. He seems to have a prejudice for the posterior approach rather than an objective view in my opinion.