Giant strides for Utah surgeon
Doctor spends years devising simpler way to treat leg deformitiesBrandon Freeman, 25, and his son Trevan, 3, stand side by side on straight legs, despite the fact both were born with a hereditary condition that causes bowed legs and other problems.
Dr. Peter Stevens goes over X-rays of a former patient whose bowed legs have been corrected by the "8-plate," which he invented.
While they shared a diagnosis, the treatments could not have been more different. Dr. Peter M. Stevens is treating a new generation - often the children of former patients, as in this case - in a much simpler way.He experimented until he came up with what he calls an "8-plate," the name chosen because the little titanium plate is shaped like a figure 8. The key to understanding how significant that lightweight piece of material is hinges on understanding how cumbersome treatments have always been.
Between ages 5 and 10, Brandon Freeman had a number of surgeries, Stevens painstakingly cutting and rotating the bones to reposition the boy's hips and upper thighs. He then anchored them with metal plates and long screws. In later surgeries, Brandon Freeman recalls, he also had staples.
He was lucky, because some of his siblings had to have both their upper and lower leg bones repositioned, he says now. He recalls vividly the long days in the hospital, then weeks and weeks encased in a cast from the waist down while it healed. Then more weeks, in physical therapy, always knowing there was probably another surgery coming. Some patients with similar surgeries had large metal "frames" placed around their legs.
When Freeman and his wife, Haley, took their little boy to Stevens, they didn't know that Stevens has spent years working on improving and simplifying the techniques and tools used to guide bone growth and repair deformities such as knock knees and bowed legs resulting from a variety of problems, including spina bifida and cerebral palsy.
Stevens, a professor in the Department of Orthopedics at the University of Utah and pediatric orthopedic surgeon at Primary Children's Medical Center and Shriner's Hospital, used the tiny 8-plate to straighten Trevan's legs, starting at age 2 - much younger than earlier techniques could have been used.
Trevan's operation was an outpatient procedure. It took the toddler a couple of days to put his weight on his legs afterward, Brandon Freeman says, not because he couldn't do it, but because he had to psych himself up to do it. He didn't need a cast, a brace or anything else. And while monitoring continues, within a year his legs were straightened, which is pretty common now, Stevens says.
The growth plate is at the heart of both old and new treatments, because it is by altering its potential in certain areas that the leg or other bone is straightened. Cartilage grows and expands and the bone comes along behind it and fills in the area, Stevens says. That cartilage is so strong that it sometimes rejects, bends or breaks the special staples that were developed for traditional osteotomy surgery.
Dr. Peter Stevens shows the cumbersome device that was used to treat orthopedic conditions before he created a simpler method.
Stevens tried his hand at developing a staple with more yield. He was unsatisfied with the result. Then he created and patented the 8-plate.
Its screws are carefully placed in the bone outside of the cartilage and growth plate so that they yield enough to let one side of the cartilage grow while controlling the other side, which lets the bone form straighter. The screws are cannulated and can swivel and spread as the bone angle is corrected.
In an article he wrote, Stevens describes it this way: "The 8-plate method of guided growth affords the opportunity to provide a tension band (rather than compression) that expedites angular correction, compared to stapling or transphyseal screws, which rely upon the principle of compression. When applied to each side of a given physis, longitudinal growth is inhibited, in the same fashion as stapling ... ." The reversible process, he notes, can be used in younger children.
Since Stevens finished his design in 2004, he has placed 8-plates in countless legs. And he's taught doctors all over the world how to do it. A surgeon can master it "in a single case."
He typically starts seeing the desired results in his patients in about three months. When its work is done, the 8-plate is removed. That doesn't guarantee, as growth continues, that another won't be needed later.
It doesn't stunt growth, he says. Pain is minimal. And a kid in surgery on Friday can be back in class on Monday. He's used them in patients 2-17. They don't do any good in patients older than that because it only works if growth plates are active.
Some surgeons who still prefer to do osteotomies (for some patients, that's the only choice, Stevens agrees) worry that the growth plate could be damaged. Stevens has not seen it happen in the 250-plus operations he's done, but the device must be precisely placed. It has guidewires, and he checks the image (cartilage doesn't show up, but the guides do) before he screws it in.
Stevens believes there are other conditions it might one day help, including spinal curvatures.
By Lois M. Collins
Deseret Morning News
Pictures by Mike Terry, Deseret Morning News
(4th picture) Dr. Peter Stevens holds his 8-plate,and the device that was used for the same condition.
(5th picture) X-rays show how plate; invented by Dr. Peter Stevens corrected a patients bowed legs.
