Limb-length Discrepancy: Lukas’ Story
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Lukas and his twin sister were born early — their mom, Melanie, was only 28 weeks into her pregnancy when a medical emergency sent her into labor. Like many preemies, the twins spent some time in the NICU, but their overall outlook was good.
When they were six weeks old, Melanie noticed that Lukas, generally the quieter, more laidback twin, was unusually fussy and didn’t want to be held. It turns out he had a staph infection, acquired through his PICC line in his leg. Because of the location of the infection, it damaged the growth plate of his right femur.
At the time, hospital staff “told me he might have problems with the growth of the bone, but he might not,” says Melanie. “I didn’t think too much of it at the time. It was one of many things they were telling us might or might not happen as the twins grew up.”
Over the next five months, both twins thrived, and Lukas’ parents didn’t notice any issues with his leg. But at a routine well-baby appointment, the pediatrician noticed a slight limb-length discrepancy between Lukas’ legs. Imaging showed his right leg was about a half inch shorter than his left, and that it bowed slightly inward. The doctor recommended Early Intervention services, physical therapy and orthotics.
Lukas began working with a physical therapist and received an orthotic insert for his right shoe so his legs would be more even as he learned to walk. The family also regularly saw an orthopaedic doctor at Children’s Hospital of Philadelphia (CHOP), which has a specialized Limb Preservation and Reconstruction Program. If Lukas was going to need care for a limb difference, he was in the right place.
While CHOP isn’t the closest hospital to Lukas and his family, who live in southern New Jersey, Melanie said driving to CHOP’s Philadelphia campus for appointments was well worth it. “From day one, we’ve had nothing but positive experiences there,” she said. “I’m so grateful that I live within an hour of a hospital like CHOP.”
Over the next few years, Lukas’ right leg grew at roughly half the rate of his left. He was prescribed a series of progressively larger orthotics — and he needed a new one each time his shoe size changed or the limb-length discrepancy increased. With the orthotics, his legs functioned well; Lukas even successfully learned how to ski. But as the length difference between his limbs grew, it began to affect his gait.
“It reached a point where the lift got too big,” Melanie says. “It was heavy and couldn’t bend so he couldn’t run, which is hard for an active young boy.”
In consultation with B. David Horn, MD, an attending orthopedic surgeon who specializes in conditions affecting the feet, legs, hips and spine, the family opted for a surgical solution. The summer Lukas turned 11, he had the first of two surgeries to lengthen his femur (thigh bone).
When it came to choosing a limb-lengthening surgery, Melanie said she and her family didn’t hesitate. Lukas had known since he was young that this was a possibility, so he was prepared for it, and they had a lot of faith in the team at CHOP.
“Dr. Horn’s bedside manner is awesome,’ Melanie says. “I had total confidence in him.”
For the first procedure, Dr. Horn cut Lukas’ femur and implanted a magnetically controlled lengthening nail into the bone. After allowing the bone to begin healing for a few weeks, Lukas’ family was taught how to use an external magnet to activate the nail – while inside Lukas’ leg – to lengthen by one millimeter each day.
Because the implanted nail is activated by a special magnet, Lukas didn’t have to wear an external device on his leg. Melanie said Lukas didn’t indicate any discomfort with the process, but he did need to use crutches to keep from bearing weight on his right leg. Over the next 50 days, Lukas’ femur was lengthened by 5 cm (nearly 2 inches). Afterward, Lukas had physical therapy (PT) to strengthen his leg. A year later, after the bone had solidified and strengthened, the nail was removed.
As Lukas hit adolescence, he had a growth spurt which resulted in another significant limb length discrepancy.
At 14, Lukas had a second procedure, this time with an 8 cm (more than 3 inches) lengthening nail which again slowly lengthened his femur — one millimeter per day over 80 days. He recently finished his follow-up PT, and his clinical team expects to remove the nail this summer, when he’s 15.
After gaining almost 5 inches of length in his right leg, Lukas still has a slight length discrepancy between his legs, but it’s not noticeable to the casual observer. Best of all, his condition no longer limits his activities. He’s a competitive player on his high school tennis team and loves bowling.
Lukas is still young and has not finished growing yet, so a third procedure may be needed down the road. At that point, he’ll have two options depending on the size of the discrepancy: Either a third limb-lengthening procedure, or – if the difference is smaller – he could opt to shorten his longer left leg to match right leg.
For now, Lukas is enjoying being able to do the things he loves without discomfort.