Volume 16 Number 4, SUMMER 1999

way to grow

by christie knudsen

Related stories:
Is Limb Lengthening for the Little?
The Magician from Kurgan

IT TOOK ONE SURGERY TO BREAK HIS LEG, SIX MONTHS TO LENGTHEN IT, AND THREE MONTHS TO HEAL, BUT FOR 14-YEAR-OLD PAUL YOUSEFI IT WAS ALL WORTHWHILE WHEN FOR THE FIRST TIME HE WALKED WITHOUT A LIMP WITH HIS FRIENDS AT SCHOOL.

Paul's right leg was slightly shorter than the left when he was born and as he grew the disparity increased to two inches. Three years ago, Paul, who was tired of wearing a shoe lift to equalize his legs, endured a procedure that sounds like something from a medieval torture chamber.

Paul's doctor, Lawrence Rinsky, MD, a pediatric orthopedic surgeon at Lucile Packard Children's Hospital at Stanford, performed the operation that began the arduous process. Rinsky, a Stanford professor of functional restoration, inserted stout pins into Paul's right shin bone -- his tibia -- and anchored the pins to a "fixator," a metal device on the leg's surface that stabilizes the pins. Then he drilled holes in the bone between the pins, without disturbing the marrow, and cracked it with a device attached to the fixator.

After the surgery, Paul rested in the hospital for three days, a typical hospital stay for limb-lengthening patients. His leg didn't hurt, he says, because he received continuous pain medication. Paul left the hospital on crutches, like all patients undergoing leg lengthenings.

At home, Paul turned a crank on the fixator each evening to pull apart his fractured tibia one millimeter daily. Within seven weeks, he had added two inches to the short tibia -- enough to equalize his legs. Then, over the next 17 weeks, the fixator, still attached to his leg, was used to push and pull the ends of the fractured bone into and out of the two-inch gap (picture someone playing an accordion), in order to facilitate the growth of bone cells in the gap.

It sounds painful, but it wasn't, says Paul. "I've heard that some people need pain medication during the lengthening, but I didn't." Paul did have his challenges, however. "Getting around on crutches was pretty hard," he says. "I also developed a minor infection around one of the pins."

Even though most patients have a successful outcome, infections around pin sites and other more serious complications are common during limb lengthening, says Rinsky. "Studies show that patients have at least two or three complications while wearing the apparatus, like dislocated joints, failure to heal, misalignments requiring additional surgery and so on."

The risk of soft-tissue damage is especially high. "Theoretically, you could lengthen bone indefinitely, but nerves, vessels and muscles can tolerate only a finite amount," says Todd Lincoln, MD, the other pediatric orthopedic surgeon at Lucile Packard Children's Hospital doing limb lengthening. "That's why lengthened limbs tend to be weaker, even though patients do intensive physical therapy," says Lincoln, an assistant professor of functional restoration. Eventually, patients regain normal strength, adds Rinsky.

A RISKY PROCEDURE

Most orthopedists won't do limb lengthening, citing the frequency and seriousness of complications. Many view am putation as a better alternative for an adult whose legs' lengths differ by more than eight inches as it is safer and, if the patient uses a high-quality prosthesis, just as effective. Those specialists who will do limb lengthening -- numbering several hundred out of 1,200 total board-certified orthopedists -- tend to be at medical schools, although a few private doctors also offer the procedure. And most orthopedists, including Rinsky and Lincoln, will not lengthen the limbs of dwarfs and other people who want to gain stature (see "Is Limb Lengthening for the Little?" page 18).

Another reason that the procedure isn't more widely available is the fact that the surgical technique is difficult to learn and not routinely taught during general orthopedic residency. The Ilizarov, the most adaptable technique, is especially challenging to master, says Rinsky (see "The Magician from Kurgan," page 18).

But even though limb-lengthening surgery is complex, it typically takes just two to four hours when done by an experienced surgeon, which is a fraction of the time consumed by clinic visits. While their new patients -- about three to five per year -- are in the lengthening phase, Rinsky and Lincoln see them three to four times per month to X-ray the bone and check for complications.

After pins and fixators are removed and until the bone has healed, patients come to clinic about once a month. For Paul, this phase lasted three months, while he wore a weight-bearing "boot" to stabilize the lengthened tibia.

Once the lengthened bone has thoroughly healed, patients are monitored annually for years. Young patients are followed for as long as 15 years.

Rinsky and Lincoln follow their patients into early adulthood because many, including Paul, need another lengthening or other treatment. Since completing treatment two-and-one-half years ago, Paul's left leg has continued to grow faster than his right, so he is beginning to limp again. He'll see Rinsky later this year to help decide whether or not he'll undergo another lengthening. He says it's a difficult decision because lengthening the short leg maximizes his height, but takes a lot of time and work, while reducing growth in the normal leg requires one quick surgery. (To reduce a bone's growth, the orthopedist drills a hole through the growth plate one to three years before its anticipated closing.)

Given the complications associated with limb lengthening and the fact that many children need an additional surgery, it's no surprise that Rinsky and Lincoln won't treat every would-be patient. "We screen patients very carefully to guarantee they're doing this for medical, not cosmetic, reasons," says Lincoln. "We want the child and the family to have a clear understanding that this is a very long, often-painful process."

Clearly, limb lengthening is a time-consuming, difficult process for the doctors, too. So why do they do it? "When the disparity between the legs is 5 centimeters [about 2 inches] or greater and lengthening will make a child more functional, we'll do it," says Lincoln. "Sometimes, it's the best way to preserve limbs," says Rinsky. "Or to make them as normal as possible."

Would Paul recommend it? "Definitely!" he says. "Spending three-quarters of one year getting lengthened is better than limping and using a shoe lift the rest of my life." SM