There has been a lot of
discussion recently in public forums about hemi
resurfacing. Hemi resurfacings are not normally used by
the most experienced hip resurfacing surgeons. I have
been privileged to personally speak with many of them
and I know their negative feelings about hemi
resurfacing.

Performing a hemi resurfacing is like
only doing half the job. The past history of hemi
resurfacing has shown it to be a poor choice for most
patients. Hemi resurfacing did not have good long term
results. The basic simple explanation is that a hemi
resurfacing only placed a metal cap on the femur bone
and not a metal bearing surface in the acetabulum of the
hip. This resulted in a hard metal surface rubbing
against cartilage and unprotected bone of the hip. Some
hemi resurfacing patients were lucky and did not require
revision surgeries, but most required revision of their
early hemi resurfacings to a THR. The early hemis were
not convertible to total hip resurfacings.

Surgeons explain that a modern hemi
resurfacing can possibly be converted to a total hip
resurfacing if the femur cap was placed properly. Since
the really experienced hip resurfacing surgeons don’t
use hemi resurfacings, a patient will normally receive
such a surgery from a less experienced hip resurfacing
surgeon or even a THR surgeon. Sometimes a hemi
resurfacing never stops the hip pain a patient
experienced due to the metal on bone situation a hemi
resurfacing causes. If the hemi resurfacing is
successful in the short term, it is very unlikely that
it could last even two years in a very active person
according to most experienced hip resurfacing surgeons.
So why would a patient want to accept a surgery that
would require a second major revision of their hemi
resurfacing after only a couple years? Also such a
revision might not be convertible to a total hip
resurfacing if the femur cap was not placed properly.

Therefore, hemi resurfacing is not
suggested by the experienced hip resurfacing surgeons.
They prefer to do a total hip resurfacing with both a
metal cap on the femur bone and a metal cup in the
acetabulum of the hip. This is a complete metal bearing
device that has developed a history of success for many
years. Some metal on metal hip resurfacings are
currently still successful at over 16 years.
Technically, hip resurfacing will last as long if not
longer than a THR. Although modern hip resurfacing is
still a newer surgery option, it is quickly proving to
be a long term, successful surgery compared to the old
hemi resurfacing option.

Hemi Resurfacing
by Dr. Bose

Hemi resurfacing in theory appears to
be an atttractive idea. However experience has proved
otherwise. In a hemi resurfacing, the metal cap
articulates with the natural articular cartilage of the
acetabular socket. This ‘bearing” works reasonably in
elderly inactive patients and fails rapidly in someone
with an high activity level.

The metal on cartilage bearing is commonly use in a
hemiarthroplasty of the hip which is done for femoral
neck fractures in the elderly. This is probably one of
the commonest procedures in orthopaedics all over the
world. Elderly, sedentry patients have a high incidence
of femoral neck fractures and typically they would
receive a hemi arthroplasty. However if someone is a
little younger and more active a hemiarthroplasty will
cause destruction of the cartilage ( chondrolysis) and
pain and it has to be converted to a THR. I have done
many of these conversions. Therefore the world over
surgeons would do a THR straight away in femoral neck
fractures if the patient has a higher activity level.

Since resurfacing by definition is for younger active
people, the metal on cartilage bearing is at a high
chance of early failure. ( there have been some
exceptions). Hence I would not use it in my practice.
Some surgeons would argue that if the cartilage fails
then they would convert to a total resurfacing. While
the argument is valid in theory, technically a
conversion of a hemi to a total resurfacing is complex.

I hope that this clarifies the issue.

with best regards

vijay bose
chennai

Hemi
Resurfacing by Dr. Schmalzried

The indications for hemi-resurfacing
are quite narrow. The joint disease should be limited to
the femoral side, such as avascular necrosis or trauma –
but without evidence of acetabular cartilage
degeneration (narrowing of the joint space or
development of any bone spurs). The pain relief is
unpredictable and generally not as good as with a total
hip resurfacing.

Thomas P. Schmalzried, M.D.

Hemi
Resurfacing by Dr. De Smet

Koen De Smet ANSWER/ANTWOORD] In the
US for long they were doing hemiresurfacings because
full resurfacings were not working well and the Metal on
Metal resurfacing was not FDA approved yet. The results
indeed are not so good. The hipscores after a time are
certainly not perfect, not what we can get with a total
resurfacing!

The hemiresurfacing also is only kept for people with an
avascular necrosis of the hip, not for any other
condition, so the indication is not so big. The problem
in these cases is that after time the metal head that is
resurfaced will give osteoarthritis symptoms because it
is wearing out the cartilage of the acetabulum. If the
patient has had a hemiresurfacing that is a component
that matches with a total MOM resurfacing and the size
of the head is not put too big, they can have a full
resurfacing done with the head implant kept on!
Unfortunately this is not always possible and most of
the time not possible.

There are indeed cases that can stay long with this
device, hemiresurfacing, but it is certainly the
minority.

Looking into the indications to do a hemi, avascular
necrosis is known to be a condition that gives the less
good results in any prosthetic implant. (In my series
with resurfacing and ceramic on ceramic in young people
I can not state or proof this)

Greetz
KOEN
Koen De Smet
AMC Gent
Anca Medisch Centrum – Anca Medical Center GHENT
Hipsurgeon
Krijgslaan 181
9000 GENT
BELGIUM
www.heup.be

www.hip-clinic.com
+3292525903

Hemi
Resurfacing by Dr. Rogerson