Mr. Mark Bloomfield
Consultant Orthopaedic Surgeon FCS(SA)Ortho
650 Hip Resurfacings to date
Mr. Bloomfield responds to the The
Times Article: “Is hip resurfacing the best solution
Let’s start at the beginning!
Fact No. 1 : Nothing is as good as nature’s own. Nothing can
ever replicate the perfection of your native, original hip –
before it became diseased. One day, maybe we can grow you a
new one, then this debate will be irrelevant. Everything
else is a compromise. Some compromises are better than
others, and it depends on the individual patient, their
activity or age, as well as the experience of the surgeon
and the quality of components used.
Fact No. 2: However you ‘spin’ it, Conventional total hip
replacement or THR is effectively an amputation of the head
& neck of the femur. No if’s and’s or but’s. Once it is
gone, that’s it, no going back. So, even if hip resurfacing
[I call it BHR as I only use the Birmingham device] has a
SLIGHTLY higher failure rate than THR, it is still worth
thinking about the preservation of your femoral head & neck.
The younger or more active you are, the more important this
Fact No. 3: The article only looks at revision rates when
comparing BHR to THR. It says nothing about other, more
subtle problems with THR like dislocation. OK, dislocation
maybe rare with THR and almost unknown with BHR, but it is
still a great concern in the early recovery phase. The fear
of dislocation with THR drives the rehabilitation in the
first few weeks and greatly restricts the advice the surgeon
can give patients. Patients have to be given guidance to
avoid dislocation which is often more onerous than is
strictly required so that everyone can ‘cover their
backsides’ so to speak. With BHR, my team is now [or should
be!] telling MOST patients there are no special or onerous
restrictions. Patients can sleep on their sides. They do not
need raised toilet seats at home. They do not need to worry
about dislocation because it is almost impossible. It allows
the patient to recover full range of motion earlier and more
safely. Unless there are concerns about bone quality,
patients can be told to get back to activities of daily
living as fast as their body allows. The only thing we have
to be a bit cautious about is high impact stuff like running
or jogging, football, rugby, skiing and the like. These can
be allowed after the 3 or 4 month x-ray and if surgeon is
happy that the danger of neck of femur fracture has passed.
The other, very subtle and impossible to quantify downside
of THR is that surgical invasion of the femoral medullary
canal forces marrow contents into the bloodstream. The bone
marrow of the long bones is where your body makes all your
blood cells. Red ones, white ones and platelets. It is why
dogs love the marrow of a bone so much – it is rich in fat
and protein. Forcing this marrow fat, rich in immature blood
cells and other proteins, triggers an inflammatory cascade
in the leg around the whole length of the femur and in the
lungs which filter the globules before they would enter the
circulation to the brain or other major organs. When severe,
this phenomenon is called fat embolism. BHR dramatically
reduces this embolisation phenomenon and is why I feel quite
happy doing bilateral BHR when the patient has bilateral
disease, but I would be very, very careful or wary of
bilateral THR on the same day. In fact I tried bilateral THR
several times before BHR came along and had lots of trouble.
Done over 30 cases of bilateral BHR now and never regretted
it. A truly astonishing operation as patients take only one
or 2 more days to go home as compared with a single side BHR.
i.e the recovery time is not doubled.
Fact No. 4: Some of us have always instinctively realized
this, but BHR is exquisitely sensitive to accurate component
positioning, and the exact metallurgy/manufacture of the
components. THR can be put in quite sloppily and still work.
At least for more than the 3 years the Times article is
looking at. The figures in the UK National Registry are for
all surgeons, using all the currently available hip
resurfacing prostheses in varying mix. One should look ONLY
at high volume, experienced surgeons to get the true
picture. I wish I had the time and energy to look in detail
at my own series, but it is certainly less than 4% failure
at 3 years! The other trouble is that McMinn has already
published large, detailed series so does the world need yet
another one? McMinn’s own figures, particularly in the under
55’s are so good, many thought he must have fabricated them.
I think less than 1% ‘failure’ at 5 years, not 3 years. This
is the problem with raw statistics: they are so easily used
like a drunk man uses a lamppost – more for support than
So much of the ‘failure’ we are looking at is due to poor
surgery, poor prostheses or a combination of both. Women are
only more at risk because their hips tend to be smaller,
therefore the precise positioning of components is more
critical. Women also tend to naturally have slightly weaker
or less dense bone than men, so their cups may not integrate
as planned or they may fracture through the neck of the
femur. Apart from that, I personally don’t believe there is
any great gender difference.
Fact No. 5 ALVAL or metal ion ‘allergy’ is very, very rare.
Irritation from excessive metal wear from poorly positioned
or poorly manufactured prostheses accounts for the vast
majority of the so-called ALVAL being reported. It sounds to
me like Andrea had excessive metal wear leading to
predictable irritation, fluid accumulation around the hip,
and pain. Andrea, I do not think you had true ALVAL. Indeed
your surgeons tend to confirm this as they did not find the
masses of inflammatory tissues and destruction that would
have been present if you had true ALVAL. The Melissa test is
useless for predicting who will get ALVAL. The Melissa test
has been used to justify large scale extraction of dental
fillings from people, particularly in Scandinavia, on the
basis that allergy to the metal in the fillings was making
these people ill. Mass hysteria on a quite fascinating
scale, and remember for very tidy profit. ALVAL is not
confined to BHR. It is a problem with any metal-on-metal
bearing couple. If ALVAL is used as a reason to discredit
BHR, then all metal on metal bearings would have to be
suspect. Which would leave only metal or ceramic on
polyethylene, or ceramic on ceramic.
So lets look at metal or ceramic on polyethylene.
Polyethylene is basically like hardened wax. Soft and
slippery. Under pressure and when heated, it deforms or
flows, just like melting wax. You can make the wax a bit
harder, but it is still wax. There are constantly new or
improved polys on the market. We have been here before.
Let’s look at Hylamer, a trade name from De Puy:
Hylamer polyethylene was introduced in the 1990s as an
alternative to conventional polyethylene. Its chemical and
physical properties, and especially its high crystallinity,
were claimed to improve resistance to wear. Initially
Hylamer devices were sterilized by gamma radiation in air,
then the technique was changed and gamma radiation was
performed in the absence of oxygen. Clinical experience has
shown the early loosening of some devices made from Hylamer.
The text understates the problem. Hylamer was an unmitigated
disaster and has long ago been withdrawn. So I don’t trust
poly in any shape or form FOR YOUNG ACTIVE PATIENTS. I still
use it for the more elderly and sedentary. It still works
perfectly well in this group.
What about ceramic-ceramic? This is the best alternative if
you cannot have metal-metal for any reason. BUT some ceramic
hips squeak. So loudly they can be heard across a room full
of people. Ceramic is brittle and although ceramic fracture
is now rare, it still happens and is under-reported. Ceramic
ages or oxidises in the body and this can then lead to
higher wear rates as the ceramic surfaces lose their shine
or surface finish. Finally ceramic-ceramic is a very ‘hard’
bearing couple with no ‘give’ or shock absorption. BHR will,
in most situations, have a thin film of fluid which can be
displaced to absorb shocks at bearing interface.
So, in summary: Yes, BHR will likely ALWAYS have a very
slightly higher revision rate than THR at 3 or 5 years, when
comparing like for like in terms of young active patients.
But the increased risk should be of the order of 1% or less,
in the hands of an experienced surgeon. Not the 7 to 14
times quoted. It is the 30 or 40 year comparative results
that will tell a different tale!
BHR revision, if ever unfortunately required, will always be
easier than THR revision. Pity the poor patient whose THR
fails early, or even later, particularly if the femoral side
needs to be redone – their surgeon has a much tougher job on
his/her hands. And abandoning BHR in favour of THR would
mean abandoning all the more subtle advantages of an
anatomical-sized component sitting on top of your own
We need to focus on precise surgery, good patient selection,
the very best metallurgy and manufacture, not scare
ourselves into abandoning the most revolutionary development
in the field of hip arthroplasty in the last 50 years.