This week’s Orthopaedic Crossfire® debate was part of the 19th Annual Current Concepts in Joint Replacement® (CCJR®), Spring meeting, which took place in Las Vegas. This week’s topic is “Dual Mobility: “Everyman’s” Choice for High Risk & Recurrent Dislocation” For is Paul F. Lachiewicz, M.D. – Duke University Medical Center, Durham, North Carolina. Opposing is Thomas P. Sculco, M.D. – Hospital for Special Surgery, New York, New York. Moderating is William J. Maloney III, M.D. – Stanford Hospital & Clinics, Stanford, California.
Dr. Lachiewicz: I’m going to convince you that the dual mobility is now the implant of choice and certainly much better than constrained liners.
There’s a long history of these designs in Europe where they’ve been used as an alternative to both large heads and constrained liners. The first one, in France for primary total hips, is now almost over 40 years old.
We presume that there is greater range of motion because you have 2 articulations and there’s increased jump distance with the very large polyethylene “head.” Some preliminary data supports our presumption from both manufacturers and independent labs.
One criticism we hear is, “Well, perhaps there’s going to be greater wear with this large polyethylene articulation.” And there was a study (Loving, et al., J Arthroplasty, 2013) that showed as long as there is some movement of the interbearing—and it’s not quite clear how much—the polyethylene wear is going to be quite low. If you do lock it and make the polyethylene be the primary articulation, you can have larger wear volumes.
There is a wide variety of European designs and for those of you who are not aware of this, there are many designs in the U.S. as well.
What are the present indications for dual mobility? Recurrent dislocation, revision of a metal-metal resurfacing and revision of a hemiarthroplasty. We use it in the second stage of an infection reimplantation, if a constrained liner fails, and Matt Abdel won a Hip Society Award for essentially saying that perhaps this is the thing to be used for all revisions.
In terms of primary total hips, I use this in patients with spine deformities and with a prior lumbar arthrodesis.
I did one of the first retrospective reviews (Lachiewicz, et al., JAAOS, 2012) and in 2012 there were only nine papers on this subject and we still showed over 90% success rate. That same year the Swedish Registry reported a 99%, two-year success rate (Hailer, et al., Acta Orthopaedica, 2012).
The same year, the UK experience (Vaskutty, et al., Bone and Joint J, 2012) came out with a French design—again a very low rate of early dislocation. At that time there were ten studies.
Since then there have been three systematic reviews published in the last year.
