November 16, 2011
Original Link  http://www.orthosupersite.com/view.aspx?rid=89618

The retrospective study, which analyzed 925 hip resurfacings performed by
Edwin Su, MD, between 2004 and 2009 with a minimum follow-up of 2 years, looked
at three implants: Wright Medical’s Conserve Plus Total Resurfacing Hip System,
Biomet Orthopedics’ ReCap Femoral Resurfacing System and Smith & Nephew’s
Birmingham Hip Resurfacing System. Conserve Plus and the Biomet ReCap were used
as part of clinical trials, while the Birmingham hip was used after FDA approval
of the implant in 2006. Clinical scores and radiographs were obtained at 1
month, 3 months, 1 year, and every subsequent year. The hips in the study had a
minimum of 2 year follow up, both radiographically and clinically. “[The Conserve Plus hip] was not FDA approved by our government between
2004-2008, so we had to petition for each patient to have the device, limiting
the numbers of patients receiving that implant,” Su, from the Hospital for
Special Surgery in New York, said during his presentation at the 12th EFORT
Congress 2011.

Su received training from some of the pioneers of hip resurfacing, in both
California and Europe, to gain the experience necessary to perform the
procedures. He used a posterior approach during the procedures and was careful
to preserve the retinacular vessels and soft tissues to prevent the need for
reoperation. The implant specific guides were used to ensure central positioning
within the neck to prevent notching, and cemented femoral fixation was used, the
study stated.

The study showed 12 revisions (1.3%) at a minimum followup of 24 months. The K-M
survival curve overall for the procedure, using all 3 different implants, was
98.6% at 68 months. Su noted that these results compared favorably to other
published papers that describe short-term failure rates of 8% and 13% for the
procedure. The Conserve Plus series had six revisions out of 157 cases (3.8%),
which involved two cup loosenings, three femoral loosenings and an adverse metal
reaction. The Birmingham series had six revisions out of 748 cases (0.8%), and
the ReCap had no revisions.

Limitations for the study include the limited amount of data collected for
certain implants, such as the ReCap, which had 20 implants compared to the
Conserve Plus (157 implants) and the Birmingham series (748 implants). The
Conserve Plus series also had a longer follow-up compared with the Birmingham
series.

“For a surgeon contemplating adopting resurfacing, one must be concerned about
the learning curve,” Su said. “The exposure is more difficult, it is more
time-consuming, and it is more sensitive to technical errors.” However, with
careful patient selection, proper surgical training, and a good implant, the
success rate can be excellent.

Reference: •Su E. A single US surgeon experience with the adoption of hip
resurfacing using 3 different implants. Paper #1140. Presented at the 12th EFORT
Congress 2011. June 1-4. Copenhagen.
•Berend KR, Lombardi AV, Adams JB and Sneller MA. Unsatisfactory surgical
learning curve with hip resurfacing. J Bone Joint Surg Am. 2011; 93S:89-92.
•Mont MA, Seyler TM, Ulrich SD, et al. Effect of changing indications and
techniques on total hip resurfacing. Clin Orthop, 2007;465:63-70
•Edwin Su, MD, can be reached at the Hospital for Special Surgery, 535 East 70th
Street, New York, NY, 10021; 202-606-1128; email: sue@hss.edu.
•Disclosure: Su provides consulting services for Smith and Nephew Inc. on hip
resurfacing products. Smith and Nephew Inc. and Biomet Inc. have provided
research support for studies involving hip resurfacing.