PROXIMA HIP
View Video of Bilateral Patient
The profile of the patient presenting
for total hip replacement has changed. Pain and disability are no longer the
only indications for surgery. The millennium patient, empowered with
information, seeks surgical intervention to restore quality of life. Thus, even
younger patients are presenting for total hip replacement. Conservative surgery
embraces both soft issue sparing and bone conservation. If the surgeon is
confident the hip he is going to use will outlast the patient he should use it.
Otherwise he should consider the next operation and conserve bone.
Any implant that makes contact with the
diaphyseal cortex or is ingrown distally will offload distally with consequent
proximal stress protection. Bone conservation is achieved both by taking less
bone at the time of surgery and by optimising the physiological loading of the
proximal femur to preserve bone in the longer term.
Elegant biomechanical studies have shown
that the PROXIMA is not a “fit and fill” prosthesis. Excellent axial and
rotational stability can be achieved within the cancellous bone, and the implant
is suspended in and moves in consort with the surrounding cancellous bone. This
reduces the shear stresses at the fixation interface and optimizes load transfer
in the metaphysis.
The technique for the insertion of the
PROXIMA is ideally suited for minimally invasive surgical approaches. The
“MicroHip” technique uses a section of the anterior Smith-Peterson approach.
This is a truly internervous and intermuscular plane which provides excellent
access to the hip joint. Minimal soft tissue disruption, together with bone
preservation, makes PROXIMA a truly conservative option for the millennium
patient.
Indian Orthopedic surgeon performs first " Proxima" hip replacement
in South India
December 05, 2006
Health News
(PRLEAP.COM) A 33 year old South Indian house wife suffering from a
condition called Osteonecrosis; or avascular necrosis of
both hips underwent a novel form of bone preserving hip replacement at
the Bharathi Rajaa Specialty Hospital in Chennai, India this week.The
technology has been introduced recently in India and
Dr.A.K.Venkatachalam is the First Indian Surgeon to perform the
operation in South India. The prosthesis implanted was the Proxima Hip
Replacement, which is a very small prosthesis.
"The size of the implant is smaller and provides maximum direct contact
with bone, besides increasing the longevity of the surgical procedure
and eliminating thigh pain," says the surgeon. "It preserves more bone
than traditional hip implant surgeries, but lesser than what hip
resurfacing does.
Dr Francesco Saverio Santori an Italian Orthopaedic surgeon in
association with a British Surgeon has designed this prosthesis and it
has a ten year follow up.
Dr.Venkatachalam says that it is novel as the bone in the neck of the
femur (Upper end of the thigh bone) is preserved. This type of hip
replacement is a solution to selected group of patients who are not
suitable for Surface hip replacement and in whom a total hip replacement
is an option. This replacement surgery preserves bone stock, as the
prosthesis is not implanted deep within the thighbone. It is a
stemless stem. The bearing surfaces are made up of metal
and this confirms enormous longevity to the prosthesis. It is also very
stable as the diameter of the prosthesis is large and replicates the
normal size of bone.
At present, minimally invasive surgery is the main trend of orthopaedic
surgery and involves almost all its fields, joint replacement included.
A total hip arthroplasty should be considered minimally invasive not
just because it can be done through a small incision but it should
preserve bone and only if bone resection is limited to pathologic
tissues (conservative replacement) and the procedure is performed
without major sacrifice of soft tissues. This last statement suggests
that the term ;mini-incisions be substituted with ;mini-approaches meaning surgical approaches that respect
the skin, but also fascia, tendons and muscles. Bone preservation may be
obtained through proximal load, neck-retaining and resurfacing implants.
Evaluating bone sacrifice both on the femoral side and on the acetabular
side, neck-retaining arthroplasties seem to warrant the most balanced
maintenance of bone tissue. Neck-preserving implants through a lateral
or posterior mini-approach seem to be the most consolidated solution in
minimally invasive total hip replacement.
It could be used in selective cases of hip arthritis, such as for people
with good bone stock for whom resurfacing would not be suitable and a
total hip replacement would be too radical.
Recently the same surgeon at this Hospital has performed a number of
minimally invasive Knee Replacements with the high flex knee for
patients including UK and Middle East.