The
BIRMINGHAM HIP Resurfacing implant is not brand new. It has
been in use around the world since 1997 and has since been
implanted more than 60,000 times. It is new to the United
States, however, where it was approved for use by the Food
and Drug Administration in May 2006.
Although hip resurfacing is not a new concept, the
technology behind the ground-breaking BIRMINGHAM HIP was
developed by British orthopedic surgeons Mr. Derek McMinn
and Mr. Ronan Treacy. The two surgeons now train
orthopedists from around the globe on behalf of London-based
medical device manufacturer Smith & Nephew. US surgeons
given access to this implant may travel to England for
specialized training or may train at one of the few US
centers capable of hosting these focused sessions.
Patient Benefits
The benefits to patients of the BIRMINGHAM HIP Resurfacing
technique and implant are clear. The implant’s head size,
its bearing surfaces, and its bone-sparing technique make it
a preferred choice for young, active patients. While the
implant’s rate of survivorship is comparable to standard
total hip replacements after five years, these three key
advantages set the resurfacing technique and implant apart
from its total hip replacement counterparts.

Head
Size
The most noticeable aspect of this implant is its size.
While it closely matches the size of your natural femoral
head, it is substantially larger than the femoral head of a
total hip replacement. This increased size translates to
greater stability in your new joint, and it decreases the
chance of dislocation of your implant after surgery.
Dislocation is a leading cause of implant failure in total
hip replacement. While total hip implants dislocate at a
rate of one to three-percent over the lifetime of the
implant, a study of 2,385 BIRMINGHAM HIP Resurfacing
patients found that dislocation occurred in only 0.3-percent
of cases five years after surgery.
Bearing Surfaces
BIRMINGHAM HIP Resurfacing takes advantage of one of the
orthopaedic medical industry’s most technologically advanced
bearing surfaces. That means that the surfaces of the ball
and the socket are made from materials that dramatically
reduce joint wear when compared to traditional hip implant
materials.
In this case, both the ball and socket are made from tough,
smooth cobalt chrome metal. Traditionally, only the ball is
made from cobalt chrome, and the socket is lined with a
plastic cup. While this plastic cup has some design
advantages, it does wear out over the course of many years
since it rubs against the metal ball at a rate of nearly two
million footsteps per year in physically active adults.
The plastic particles released into the area around the
joint as a result of this plastic wear can lead to a
condition called osteolysis, which causes the bone around
the implant to soften, become unstable, and ultimately a
corrective surgery and new implant are required.
However, when both surfaces of a hip implant are made from
cobalt chrome, wear particles are reduced by 97-percent1,
thus potentially extending the life of the implant.
There
may be risks associated with metal-on-metal hip implants,
though. While no evidence has been established on the
subject, some are concerned that the increased level of
metal ions found in the blood of metal-on-metal hip
recipients may have negative effects on the human body. For
this reason, some surgeons may not implant such a device in
a patient with kidney disease (since healthy kidneys filter
ions from your body) or in women who are or may become
pregnant.
Bone Conservation
Perhaps the greatest benefit of the BIRMINGHAM HIP
Resurfacing implant is the fact that it conserves
substantially more bone than a total hip replacement. This
is important for two key reasons.
First, unlike a total hip replacement, the BIRMINGHAM HIP
Resurfacing preserves your natural femoral neck. It is this
neck length and angle that determines the natural length of
your leg, and since it is not removed and replaced with an
artificial device during a resurfacing procedure, concerns
regarding leg length discrepancy are virtually non-existent.
Second, if your surgeon should determine you need to have
your BIRMINGHAM HIP implant replaced at some point in the
future, you may undergo a regular total hip replacement
surgery. If you had originally undergone total hip
replacement instead of hip resurfacing, you would be dealing
with a more traumatic and complex procedure and you would be
receiving a more invasive implant.