A thorough physical examination includes observation of alignment while the child stands. Also, observe their gait from different angles because “kids are good at compensating,” Dr. Iobst said. Also, assess joint range of motion and stability; motor strength, sensation, and tone; and limb symmetry.
“We need to see the entire lower extremities, so don't examine patients in jeans or shorts, use a gown,” Dr. Iobst said.
It is often helpful to predict the growth remaining in a child, Dr. Iobst said. It can be challenging because growth is not uniform but is a succession of phases. Keep in mind that height increases an average 350% from birth to adulthood, at which time weight also increases 20 times, the femur and tibia lengths increase 3 times, and the spine length increases 2 times.
Although there are more complicated methods to calculate growth remaining, Dr. Iobst recommended the Menelaus Method. “It is the simplest. You can do it in your office.” The distal femur grows 3/8 inch per year, and the proximal tibia grows 1/4 inch per year. Assume growth cessation at 16 years for boys and 14 years for girls. Use chronologic age, not skeletal age, he added, for the simplest estimate of growth remaining.
A percutaneous osteotomy incision is made while the patient wears the frame.
A circular external fixator is positioned to lengthen the tibia and fibula. Photos courtesy Dr. Christopher A. Iobst