Magnetically-Controlled Growing Rods

MAGEC Growing Rods (Part 1)

In the last blog we talked about Growing Rods for the
treatment of EOS.  The major downside to
this treatment method is the need for repetitive anesthesia and open
lengthening of the growing rods in the operating room.  Over the last 5 years there has been a number
of studies assessing the impact of repetitive anesthetics in the growing child,
specifically on brain development and behavior.
Despite the volume of research in humans and in animal models, there
remains confusion as to who is at risk, what is at risk and the magnitude of
the risk.  What we do know is that there
is a significant amount of psychological stress on children, and the parents.
The other negative for traditional growing rods is the need
for open lengthenings.  Every time
growing rods are openly lengthened creates an opportunity for a deep wound or
implant infection.  If infections involve
the Growing Rods, they typically must be removed as it is very difficult to
eradicate the infection (bacteria).  This
means surgeons commonly must remove the Growing Rods, treat with antibiotics
and then re-implant the Growing Rods at a later date. 
So it is easy to see that limiting the number of anesthetics
the child is exposed to and minimizing the number of surgical procedures is
optimal for the patients, and their families.
In the fall of 2014, a new device received FDA clearance for use in the
U.S., the MAGEC (MAGnetic Expansion Control) system.  This new device is an actuator that can
lengthen or distract when inside the patient, without the need for anesthesia
or making an incision on the child.  This
system permits lengthening of the growing rods without the need for anesthesia
and open lengthening
The lengthening of the MAGEC rod is done by placing the
device in a special magnet field.  The
MAGEC rods can be lengthened painlessly in the clinic, without sedation or
anesthesia.  In fact the lengthening of
the MAGEC rods takes less than 1 minute by a device called an ERC or External
Remote Controller, which creates the special magnetic field around the MAGEC
device.
I have personally implanted 30 early-onset scoliosis
patients with the MAGEC system; some patients were converted from a traditional
Growing Rod system and others it was their first surgery.  This system has dramatically improved the
ability to lengthen the growing rods, since even if the child is not well we
can lengthen the MAGEC rods in the clinic.
Previously if the child had traditional growing rods, and was ill, their
surgery may be cancelled because of concerns about their airway and
breathing.  Also, as mentioned earlier,
there is a lot less stress on the patient and family.  There is no need for placement of IVs, an
anxiety-provoking and sometimes painful procedure, or general anesthesia so
there is no post-anesthesia nausea and vomiting. 
 
However, MAGEC rods are not the answer for all patients with
early-onset scoliosis.  The device can be
difficult to place as it requires an almost perfectly straight area to be
placed into the back, around 12 centimeters.
At first glance this looks like all patients would have a straight area
to be able to place a MAGEC device, however it is not always the case in
early-onset scoliosis.  Sometimes it is
necessary to start with traditional growing rods and then change at a later
date to MAGEC, after the child has grown more.

Leave a Reply

Your email address will not be published. Required fields are marked *