| A fully internal,
remote-controlled limb-lengthening device heralds a
breakthrough in reconstructive surgery, whether it be for
accident victims, people with natural limb discrepancies or
those who simply feel they’re too short. JESSICA LIM
reports.
Spanner in hand, Ari poised over the chunky
metal brace caging his right leg. With four careful tweaks, he
forced the rods piercing his skin, muscle and bone to move a
fraction, bringing him a quarter of a millimetre closer to
walking normally again.
When his shin bone became badly
infected while recovering from a nasty car accident two months
ago, the 35-year-old lorry driver refused even to ponder the
possibility of amputation.
He opted for Ilizarov
surgery — a painful procedure where 7cm of infected bone in
his leg was removed, and new bone stimulated to
grow.
This is done by breaking the healthy part of the
bone and pushing the two pieces apart every six hours over six
months (a process called "distraction osteogenesis") until the
7cm gap is closed.
"It was the worst pain I’ve ever experienced,
especially the first week. I’ll never forget it till the day I
die.
"At that time, I thought ‘dying is better than
this.’ Now I’ve got used to it, it’s not too bad."
"I
feel like a rotting kayu (wood)... Can’t work, can’t go out
because people stare at my leg.
"But as long as my leg
is saved, I don’t mind. I want to get back to work and play
football again."
For decades, the painful and
encumbering Ilizarov procedure was the best chance for
shattered bones to be restored, short limbs to be lengthened
and crooked ones straightened.
Breakthroughs in
distraction osteogenesis in the past 10 years, however, have
resulted in hassle-free and less painful (albeit more
expensive) alternatives.
The most technologically
advanced option so far is a fully implantable,
electronically-motorised limb-lengthening device called
"Fitbone".
Developed in Germany, Fitbone consists of
an antenna which is buried under the skin, a telescopic nail
implant and a handheld radio-frequency transmitter.
The patient controls the lengthening process. Push a
button on the transmitter when it is placed against the
antenna and the built-in motor extends the nail approximately
1mm per day.
Dr Thirukumaran Subramaniam, who has
practised orthopaedic surgery in Malaysia, Germany and
Singapore since 1994, said the leap forward came when optimal
bone distraction rate was determined to be 1mm per
day.
"Lengthening too fast will overstretch soft
tissues, causing pain," he said.
"Also, bone gaps which
are too big will never fill up. Too slow and the bone hardens
before you complete the full lengthening
process.
"Ilizarov is infection-prone. It’s itchy,
uncomfortable, you get stared at, and often have to deal with
unsightly scars after the whole ordeal."
Ilizarov surgery was developed in Russia in the
1950s. Frames were made of stainless steel rings, which
weighed up to 7kg. Newer models are made of carbon, which,
though lighter, are equally cumbersome.
With the
introduction in 2001 of the Intramedullary Skeletal Kinetic
Distractor (ISKD), lengthening could take place internally,
drastically reducing the risk of infections and scarring.
With ISKD, a pin which could be gradually extended by
knee or ankle rotations is implanted into the bone.
Lengthening is monitored by a handheld external
magnetic sensor that tracks the rotation of an internal magnet
on a daily basis.
Dr Thiru’s teammate and fellow
orthopaedic surgeon, Dr Jeyaratnam T. Satkunasingam, said that
Fitbone improved on several weaknesses of the ISKD
method.
ISKD required a physical leg movement to
"crick" the device into lengthening, which was quite painful,
especially right after surgery, he explained.
"Patients
also risk accidentally ‘over-lengthening’ their bones, which
might prevent proper bone formation," said Dr Jeya, who was
trained in Fitbone surgery at the University of Munich,
Germany, last year after eight years of experience as an
orthopaedic surgeon.
The convenient, scar-free
procedure, however, comes at a price.
While the
Ilizarov external fixator costs RM15,000 and the ISKD implant
about 7,000 euros (RM32,000), the Fitbone device alone carries
a price tag of 10,000 euros (RM45,000).
Including
surgery costs, the Fitbone procedure would come to RM80,000 —
per bone.
Often, especially in congenital conditions,
both the tibia and femur need to be operated on to ensure
proportionate lengthening of the leg.
Sometimes, all
four leg bones must undergo surgery, quadrupling the cost of
the procedure.
Following the lengthening procedure, the
patient is confined to a wheelchair or crutches for a period
to allow the bone to gain mass.
"Growing 60mm takes 60
days," said Dr Jeya. "Thereafter, the patient must wait
another 120 days before using the leg normally.
"If a
person has both legs operated on, it takes significantly
longer because it’s not wise to operate on both legs at
once."
In the days following initial surgery, patients
must undergo a demanding physiotherapy regime — stretching
exercises and sometimes be hooked up to a "continuous passive
motion" device.
This is to avoid stiffness and to
stimulate the muscles, nerves and blood vessels to grow
alongside the bone.
Patients are often prescribed
painkillers and are unable to work.
The surgeons
recommend that bones be grown to a maximum of about 7cm per
bone, which means the individual can gain up to 14cm in total
limb length.
"Some doctors claim that they can grow
each bone by up to 12cm, but that will place great strain on
the body," said Dr Thiru.
"Besides, if your legs are
too long, you’ll look like a lemon on
toothpicks."
Factors that influence an individual’s
bone growth rate include age, discipline and lifestyle. The
bones of a smoker, for example, grow more slowly than that of
a non-smoker.
Although the procedure most often deals
with post traumatic injuries, it is increasingly used to
correct limb discrepancies caused by congenital conditions and
old injuries.
Dr Thiru and Dr Jeya both find it very
satisfying, as orthopaedic surgeons, to see patients — whose
limbs were deemed unsalvageable — walking tall and straight
again.
Some were accident victims whose shattered legs
were considered a lost cause.
Some were people who
have lived for years with congenital deformities so severe
that their doctors recommended amputation and a prosthetic
fitting.
Others were resigned to living with their
awkward gaits and misaligned postures, with no hope of
correcting them.
But now many of these conditions can
be remedied, if money is not a big issue.
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