Hips
Limited Access Total Hip Replacement
Introduction
The evolution of hip replacement technologies is
among the most fascinating stories of modern
surgical advancements. As early as 1826, Dr.
Barton of Philadelphia corrected the deformities
of the thigh bone (by breaking and realigning
the broken pieces) to treat the arthritis of the
hip. Dr. Murphy of Chicago published a similar
procedure combined with interposition of soft
tissue between the ball and socket of the hip
joint, in 1915. In 1939, American orthopedic
surgeon Smith-Peterson published his pioneering
work in which he developed and used an
artificial mould to replace the ball of the hip
joint. Dr. Bohlman and Dr. Moore separately
published an improvement on Smith-Peterson
device by attaching an anchoring peg to the
mould (the peg was Dr. Smith-Peterson’s
invention to fix the broken neck of the thigh
bone). Later on Dr. Moore and others improved
the pegged device by replacing the peg with a
stem that fitted into the shaft of the thigh
bone; these devices improved the security of
fixation and stability of the joint but did not
address the issue of pain emanating from the hip
socket. This led to the development of the
concept of total hip replacement by Mr. Ken
McKee, F.R.C.S., and Mr. John Watson-Farrar,
F.R.C.S. (a male British surgeon who is a
certified fellow of the royal college of
surgeons is referred to as Mr.) of Norwich,
England, who developed a metal cup which served
an artificial socket to go along with the metal
ball-stem component. In spite of all these
advances, secure fixation and elimination of
pain related to the motion of the components
within the bone remained elusive until Sir John
Charley developed and used bone cement to
securely fix the components to bone. The search
for alternative articulating surfaces led to the
introduction of a plastic socket and metal
ball-stem components for what was termed “low
friction arthroplasty” popularized by Sir John
Charnley, the man who immensely contributed our
knowledge of modern artificial joint technology.
The search continues for better designs; better
materials; better understanding of the hip
biomechanics; and better surgical techniques of
the artificial joints to improve the
functionality and the longevity of the device.
The purposes of
artificial hip joint replacement are to alleviate pain and improve
function. It is not necessary to replace the hip joint or any other
joint simply because radiological diagnosis of arthritis, as long as
the pain is controllable by non-operative means and that the
patient’s ability to function is not significantly compromised. Even
if pain is significant and function is compromised, the surgeon has
to determine the safety of joint replacement if there are other
significant health issues which may compromise the outcome of such a
procedure or even lead to mortality.
Although the track
record of the total hip replacement is generally good, and continues
to improve, it is not without risk, and the risks tend to be higher
in patients with other medical problems. Complications related to
the surgery may occur during surgery or at different intervals after
surgery. During the surgery nerve and vascular injuries can occur,
the bones may break during the operation and the artificial joint
components may be positioned sub-optimally leading to recurrent
dislocations. After surgery the patient may experience troublesome
recurrent dislocation of the artificial joint (which may necessitate
multiple operations), joint loosening and joint infection. A good
surgical technique can minimize these complications but cannot
eliminate them! The patient’s compliance with the doctor’s and
therapist’s instruction after surgery is of paramount importance.
Approaches to the Hip
There are several approaches used by surgeons
for total hip replacement. Most surgeons are
familiar with one approach – the one learnt
during their residency. Those who have good
experience with different approaches generally
can tailor the approach to the specific needs of
a patient to ensure a good outcome of surgery.
The most widely
used approach in the United States is through the back (posterior).
It is very safe approach and quite versatile and can be used for
complex situations. Its main weakness is the risk of dislocations.
Since the approach violates the structures which stabilize the back
of a normal hip joint, sitting on a low stool, bending low to pick
up objects, and crossing legs are all likely to lead to
dislocations. The meticulous technique by the surgeon and the
thoughtful design of the components significantly reduce, but cannot
eliminate the risk of dislocations. The approach from the side
avoids injury to the stabilizing structures at the back of the joint
and thus reduces the risk of dislocations. Its main drawback is that
it violates some muscles of the hip and may cause weakness. The
approach slightly to the front of the “true” side approach avoids
violating the stabilizing structures at the back of the joint, and
accesses the hip between muscles, thereby minimizing injury to the
muscles. The joint is accessed through the front. Approach is
versatile, and even in the hands of a less experienced surgeon is
less likely to dislocate as compared to the posterior approach.
The
Limited-Incision Approaches To Hip
I am being careful
in the choice of the terms I use here. The term “minimally invasive
surgery” is very appealing to patients and is often inappropriately
used to promote a procedure. While one can justify the use of the
term “minimally invasive” to remove a torn cartilage
arthroscopically from the knee, or remove gall bladder
laparoscopically from the belly, I would have difficulty using the
same term to describe a joint replacement procedure, irrespective of
the size of the incision. There are, often, trade-offs with the
lesser incisions, and this may impact the accuracy of implantation
of the artificial device even if auxiliary aids such as x-rays and
navigation technologies are available. I prefer to use the term
“limited-incision” approach to the hip joint, and consider the
incision size of lesser importance than the accuracy and safely of
the implantation of the artificial joint.
As many of you
know, I have a lot of interest in the least trauma surgery of the
spine, and that interest stretches to joint replacements. The goals
for this stance are to: minimize surgical trauma; reduce loss of
blood; reduce surgical pain; reduce hospitalization; shorten
rehabilitation; and facilitate return to productive activities. The
ideals of this approach also include: reducing risk of
complications; proper alignment and secure fixation of the device;
long term benefit from surgery; and reduction of treatment cost.
I learned the
technique of the total hip replacement from John Watson-Farrar,
F.R.C.S., when I was his orthopedic resident, at the Norfolk and
Norwich Hospital, in Norwich, England. As stated above, Mr.
Watson-Farrar was a pioneer in the total hip replacement technology
and has his own artificial joint which he designed and used after
the metal-on-metal device, which he developed along with Ken McKee.
Incidentally, the metal-on-metal design, based on the McKee-Farrar
concept, is now being used increasingly throughout the world. The
approach I learned from Mr. Watson-Farrar is the one which is placed
to the front of the “true” side approach. After completion of my
residency in Norwich, I went to Edinburgh, Scotland, to train as a
clinical fellow. There I learned the approaches through the back, as
well as the “true” side of the hip joint. I have used all these
approaches extensively throughout my training in different places
and in my private practice. After relocating to the United States,
during my training at the Case Western University, I used the
approach through the back for my entire time of training.
The extensive
experience in the surgery of the hip as well as the other joint
replacement technologies, has given me the unique ability to tailor
the approach to the needs of individual patients. To achieve the
goals of the limited incision surgery listed above, I shall be using
a modification of the approach I learned from Mr. Watson-Farrar for
the care of my patients, unless the specific condition of the
patient dictates otherwise. This approach has important attributes:
it can be performed with the patient lying on his or her back –
this is particularly helpful to the anesthiologist if a complication
occurs during surgery, as the patient would be in a ideal position
for resuscitation; the approach preserves the important hip
stabilizing structures at the back of the joint, therefore
minimizing the risk of dislocation, especially in the old and the
infirm patients and those patients with mental or neurological
abnormalities; the approach is through a plane between muscle groups
and thus, at least theoretically, avoids muscle damage and
facilitates a quicker and a more complete recovery of the muscles
than approaches which split muscles; while the artificial joint
implanted from the front is not immune to dislocations, it affords
more room for error of alignment of the joint components than
implantation from the back; the limited exposure reduces surgical
trauma. Surgical time in the hands of an experienced surgeon is
shorter than other approaches and return to normal activities are
expected to be quicker than the standard approaches.
Contact
Information
Dr. Osman is a fellowship trained, and
Orthopedic Board certified orthopedic surgeon.
He has admitting privileges at the Russellville
Hospital, Russellville, Alabama; and Helen
Keller Hospital in Sheffield, Alabama. He is in
the process of applying for privileges to the
Eliza Coffee Memorial Hospital, Florence,
Alabama
RUSSELLVILLE MUSCULOSKELETAL CENTER
15225 HIGHWAY 43 STE 1 P O BOX 57
RUSSELLVILLE AL 35653
www.drosman.org
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