ATLANTA (FOX 5 Atlanta) - At four and a half, Clark Jeffers isn't going to let the metal contraption wrapped around his right leg slow him down.
"He's a feisty little fellow," Ellen Jeffers, his mother, says. "He's tough."
Ellen and Brian Jeffers were surprised with the youngest of their four kids was born with just four toes on his right foot.
Doctors told them it wasn't a big deal, but when Clark was about six months old, his big sister Anna noticed something.
"She said, 'Mommy, I just think his leg is shorter than his other leg,'" Jeffers remembers.
That's how the Jeffers ended up at Children's Healthcare of Atlanta.
Pediatric orthopedic surgeon Dr. Jill Flanagan measured Clark's right leg and found it was about an inch shorter than his left, and rotating inward.
"But, as a child, the problem is, because that right limb is smaller, it will continue to grow smaller proportionately to the other side," Dr. Flanagan says. "So, he's projected to have almost a three inch difference in his limb lengths by the time he's fully-grown. That is not life or death, but it's not functional either."
So, Dr. Flanagan set out to fix the problem.
"How to lengthen a bone?" she says. "It sounds crazy, but we can do it."
When Clark was two, she surgically stabilized his lower right limb, realigning his foot under his ankle joint.
"He was into superheroes then, so Dr. Flanagan gave him a Captain America cast," Ellen Jeffers says. "So, that was the most exciting thing for him out of that surgery."
In early January of 2019, Flanagan moved on to the next step.
"This surgery, I was afraid, and I think he was afraid," Jeffers says.
With Clark was under anesthesia, Dr. Flanagan surgically broke his leg, and then attached an external fixator with adjustable cranks to slowly
"And it's like Goldilocks," Dr. Flanagan says. "If you stretch it too fast, you don't make bone, you make fibrous tissue. If you stretch it too slow, the bone will heal too quickly. So, you have to stretch it just right."
Ellen Jeffers says the first few days and weeks were difficult, as Clark struggled with pain.
But, as soon as he could stand up, Clark began physical therapy, to learn how to walk with the fixator.
"He just worked hard and got better," his mother says. "And, he slowly started leaving his walker behind."
The device seems to be paying off.
In just four months, his lower limb has grown by over an inch, and his scans show new bone seems to be forming in the break.
As he grows, Flanagan says, keeping his leg aligned, will require lots of follow-ups.
"He'll want to grow crooked, I'll grow his straight," Flanagan says. "He'll want to grow crooked again, and I'll grow him straight. My job is once he's done growing, I'll get him even on both sides and I'll get him straight."
That will require another major surgery, but this time, Flanagan says, Clark won't have to wear the metal fixator.
His prognosis, she says, is "fantastic."
"If he wants to do sports, he can do sports," Flanagan says. "He can do anything he wants to do."