Since 2011, we have been using internal bone lengthening. This has been the most significant advance in our field in the last decade. With the use of an internal lengthening nail, we can avoid the use of external fixation entirely. With bone lengthening, we perform an osteotomy (bone cut) and gradually pull the bone apart very slowly with a regular rate and rhythm. Since bone has the ability to regenerate, new bone gradually grows in the space leading to bone elongation. In the past, we could use only external fixation to gradually lengthen the bone, but now the internal lengthening nail has replaced external fixation for most long bone lengthening surgeries. A telescopic rod in inserted into the marrow cavity of the bone. A remote control device spins a magnet in the rod which turns a gear and elongates the rod which lengthens the bone. The internal method is very accurate and is safer and more comfortable for the patient compared to external fixation.