Dr. Douglas Kiester is an Orthopaedic Surgeon with an expertise in spinal reconstruction. He is a Professor in the Department Of Orthopaedic Surgery at the University of Irvine. Dr. Kiester is the inventor and patent holder on numerous medical devices. His latest invention is the MAGEC - Remote Control Spinal Deformity System. The MAGEC system recently won the 2011 Best New Technology In Spine Care Award. The first application for this device is the treatment of childhood Scoliosis. Click to see a video of the device. Here is an article in the UK Daily Mail about the device. (Now I can walk tall... all thanks to my remote controlled bionic spine)
Question) How does the MAGEC system treat idiopathic Scoliosis?
Dr. Kiester) For over 25 years I have been very certain that Adolescent Idiopathic Scoliosis (AIS) is mechanically caused by ligaments in the back of the spine that are too tight to accommodate growth. I patented the concept of treating AIS with a device that slowly stretches out the spine over time. The motor conceived in the patent was a wire that turned a ratchet when heated with a tightly directed radio wave. The head of Ellipse Technologies e-mailed me to say that they had a motor that would make my device work. Their office was located between my home and my office.
What Ellipse had was a small cylinder magnet that would rotate when another magnets was rotated near it. This would work while they were several inches apart. The device we created is a rod that can be implanted by the spine that lengthens when these magnets are activated close by on the skin. The activation mechanism is computer controlled so that the rod lengthens exactly the desired amount on each activation. Verification of the new rod length is easy to do with an x-ray.
The rod is anchored to the spine on both ends with screws. When it is activated it is like when a child goes to the dentist to get the braces on their teeth adjusted. The lengthened rod slowly stretches out the spine just like the braces slowly pull the teeth into a straight alignment.
Question) Why is your device superior to traction or stretching exercises?
Dr. Kiester) Traction can't pull hard enough to stretch out the ligaments involved. Your skin is too soft, making the traction too weak to be effective. Also while braces on the teeth pull 24/7, traction can only be applied for a limited time each day.
Exercises have been tried for literally hundreds of years without much success. Part of that failure is because people believe that the problem with scoliosis is the spine bending to the side. And so they have concentrated on doing ineffective exercises. The bending to the side is not the primary problem. That is a side effect (no pun intended). The primary problem is the ligaments in the back of the spine that need to be stretched. Again, these ligaments are too tight for flexion exercises to help much. The one exception may be Dr. Vert Mooney's trunk rotation exercises which seem to have the unexpected consequence of stretching the right ligaments, and therefore seem to be somewhat effective. Again, exercising for hours at a time is no match for the braces on your teeth that are constantly pulling.
So why don't scoliosis braces work better? No one really notices, but while the brace is being fit, the orthotist pushes the side bend toward the midline. This causes the patient to stand up straighter, and even extend their back. The brace then locks them in this position. The x-ray in the brace looks better, because the curve is less, but no one notices that the spine is now braced in extension. To stretch the culprit ligaments requires flexion which is just the opposite of extension. Now firmly braced, the spine doesn't get to bend and stretch with day to day activities. Just as soon as the brace comes off and the patient bends forward the curve goes back to where it was (or worse).
Question) Does MAGEC treat the lateral curve, rotation or both?
Dr. Kiester) What MAGEC does is stretch the ligaments at the back of the spine. It has only been in the past few years that Dr. Lenke has published that the scoliotic spine is almost always in extension. Prior to his publication, people did not understand this. As the spine is stretched, the normal forward bending is slowly restored. Now there is enough space in the front of the spine for the front of the vertebra to return toward the midline. As the spine is stretched further, the spine becomes straight. The rotation is because the back of the spine is held on the midline where the tight ligaments are, while the vertebra leave the midline to find room to grow. If the back stays in the middle while the front leaves the middle, the result is rotation. As the front is gently pulled back toward the midline, the rotation, by definition, goes away along with the curve.
Question) What does surgical implantation of your device entail? Are there restrictions after surgery?
Dr. Kiester) To anchor the MAGEC rod, pedicle screws are placed at both ends, two screws on each end for a total of 4 screws per rod. Many of the doctors who are testing this system overseas are putting two rods; one on the right, and one one the left. The normal fusion rod has many points where it is attached to the spine. The MAGEC rods are attached only on the ends. This makes them less stable than a fusion rod, so activities need to limited, and sometimes soft braces to slow down the body movements are used.
Question) How many implants will a patient receive? Where in the spine does the surgeon place the system?
Dr. Kiester) The rods are placed with one end at the start of the curve and the other end at the end of the curve.
Question) Once the device is implanted how often will it be adjusted by a physician? What happens during an adjustment?
Dr. Kiester) Our studies showed that the rod could be safely lengthened every week. For further safety the rods are currently being lengthened every 2 to 6 weeks. The child comes to the doctor's office. There is no sedation or pain medication given. The child lays face down, and the lengthening device is activated for one to two minutes. The children are not reporting anything more than mild discomfort when the rod(s) are lengthened.
Question) Is the system removed or turned off when the patient reaches skeletal maturity?
Dr. Kiester) There is nothing in the rod to turn off. The "motor" is a magnet. That's it. A simple magnet which rotates on a threaded screw. The plan is to remove the rods once the stretching is done. This involves one small incision on each end of the rod so that the anchors can be removed. The rod is then pulled out though one of those small incisions. Anytime there is metal around bone that is moving, the metal will eventually loosen, and/or break. There is no fusion with this rod. The spine is fully mobile at the end of treatment. The spine does not get stiff or fuse. Thus the rod needs to be removed.
Question) Is the MAGEC system designed for a specific type of spinal curve or can it be used to treat the broad, patient population?
Dr. Kiester) The MAGEC was designed with AIS in mind, but it has been warmly welcomed by the families and doctors treating congenital scoliosis. This is a very different condition that becomes manifest very early in a child's life. Before MAGEC "growing" rods required open surgery for each lengthening to keep up with the child's growth. As such lengthenings occur typically only every 6 months or so. Because the lengthenings are far apart, the doctors do their best to overstretch the device as much as possible with each stretching. This is very painful, and often requires several days in the hospital for pain control after a lengthening surgery. Many of the earliest patients to use the MAGEC were congenital scoliosis patients. The reviews from these doctors and patients have been very positive.
Because adult scoliosis works by yet another completely different mechanism which is now just beginning to be well understood by the more advanced spine surgeons, the MAGEC really doesn't have any place in the treatment of adult scoliosis. This technology won't work in that setting.
Question) How does the MAGEC system treat idiopathic Scoliosis?
Dr. Kiester) For over 25 years I have been very certain that Adolescent Idiopathic Scoliosis (AIS) is mechanically caused by ligaments in the back of the spine that are too tight to accommodate growth. I patented the concept of treating AIS with a device that slowly stretches out the spine over time. The motor conceived in the patent was a wire that turned a ratchet when heated with a tightly directed radio wave. The head of Ellipse Technologies e-mailed me to say that they had a motor that would make my device work. Their office was located between my home and my office.
What Ellipse had was a small cylinder magnet that would rotate when another magnets was rotated near it. This would work while they were several inches apart. The device we created is a rod that can be implanted by the spine that lengthens when these magnets are activated close by on the skin. The activation mechanism is computer controlled so that the rod lengthens exactly the desired amount on each activation. Verification of the new rod length is easy to do with an x-ray.
The rod is anchored to the spine on both ends with screws. When it is activated it is like when a child goes to the dentist to get the braces on their teeth adjusted. The lengthened rod slowly stretches out the spine just like the braces slowly pull the teeth into a straight alignment.
Question) Why is your device superior to traction or stretching exercises?
Dr. Kiester) Traction can't pull hard enough to stretch out the ligaments involved. Your skin is too soft, making the traction too weak to be effective. Also while braces on the teeth pull 24/7, traction can only be applied for a limited time each day.
Exercises have been tried for literally hundreds of years without much success. Part of that failure is because people believe that the problem with scoliosis is the spine bending to the side. And so they have concentrated on doing ineffective exercises. The bending to the side is not the primary problem. That is a side effect (no pun intended). The primary problem is the ligaments in the back of the spine that need to be stretched. Again, these ligaments are too tight for flexion exercises to help much. The one exception may be Dr. Vert Mooney's trunk rotation exercises which seem to have the unexpected consequence of stretching the right ligaments, and therefore seem to be somewhat effective. Again, exercising for hours at a time is no match for the braces on your teeth that are constantly pulling.
So why don't scoliosis braces work better? No one really notices, but while the brace is being fit, the orthotist pushes the side bend toward the midline. This causes the patient to stand up straighter, and even extend their back. The brace then locks them in this position. The x-ray in the brace looks better, because the curve is less, but no one notices that the spine is now braced in extension. To stretch the culprit ligaments requires flexion which is just the opposite of extension. Now firmly braced, the spine doesn't get to bend and stretch with day to day activities. Just as soon as the brace comes off and the patient bends forward the curve goes back to where it was (or worse).
Question) Does MAGEC treat the lateral curve, rotation or both?
Dr. Kiester) What MAGEC does is stretch the ligaments at the back of the spine. It has only been in the past few years that Dr. Lenke has published that the scoliotic spine is almost always in extension. Prior to his publication, people did not understand this. As the spine is stretched, the normal forward bending is slowly restored. Now there is enough space in the front of the spine for the front of the vertebra to return toward the midline. As the spine is stretched further, the spine becomes straight. The rotation is because the back of the spine is held on the midline where the tight ligaments are, while the vertebra leave the midline to find room to grow. If the back stays in the middle while the front leaves the middle, the result is rotation. As the front is gently pulled back toward the midline, the rotation, by definition, goes away along with the curve.
Question) What does surgical implantation of your device entail? Are there restrictions after surgery?
Dr. Kiester) To anchor the MAGEC rod, pedicle screws are placed at both ends, two screws on each end for a total of 4 screws per rod. Many of the doctors who are testing this system overseas are putting two rods; one on the right, and one one the left. The normal fusion rod has many points where it is attached to the spine. The MAGEC rods are attached only on the ends. This makes them less stable than a fusion rod, so activities need to limited, and sometimes soft braces to slow down the body movements are used.
Question) How many implants will a patient receive? Where in the spine does the surgeon place the system?
Dr. Kiester) The rods are placed with one end at the start of the curve and the other end at the end of the curve.
Question) Once the device is implanted how often will it be adjusted by a physician? What happens during an adjustment?
Dr. Kiester) Our studies showed that the rod could be safely lengthened every week. For further safety the rods are currently being lengthened every 2 to 6 weeks. The child comes to the doctor's office. There is no sedation or pain medication given. The child lays face down, and the lengthening device is activated for one to two minutes. The children are not reporting anything more than mild discomfort when the rod(s) are lengthened.
Question) Is the system removed or turned off when the patient reaches skeletal maturity?
Dr. Kiester) There is nothing in the rod to turn off. The "motor" is a magnet. That's it. A simple magnet which rotates on a threaded screw. The plan is to remove the rods once the stretching is done. This involves one small incision on each end of the rod so that the anchors can be removed. The rod is then pulled out though one of those small incisions. Anytime there is metal around bone that is moving, the metal will eventually loosen, and/or break. There is no fusion with this rod. The spine is fully mobile at the end of treatment. The spine does not get stiff or fuse. Thus the rod needs to be removed.
Question) Is the MAGEC system designed for a specific type of spinal curve or can it be used to treat the broad, patient population?
Dr. Kiester) The MAGEC was designed with AIS in mind, but it has been warmly welcomed by the families and doctors treating congenital scoliosis. This is a very different condition that becomes manifest very early in a child's life. Before MAGEC "growing" rods required open surgery for each lengthening to keep up with the child's growth. As such lengthenings occur typically only every 6 months or so. Because the lengthenings are far apart, the doctors do their best to overstretch the device as much as possible with each stretching. This is very painful, and often requires several days in the hospital for pain control after a lengthening surgery. Many of the earliest patients to use the MAGEC were congenital scoliosis patients. The reviews from these doctors and patients have been very positive.
Because adult scoliosis works by yet another completely different mechanism which is now just beginning to be well understood by the more advanced spine surgeons, the MAGEC really doesn't have any place in the treatment of adult scoliosis. This technology won't work in that setting.
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