Limb length discrepancy (LLD) is a common condition defined by the unequal length of paired limbs with estimated rates of 40–70% and 1/1000 people experiencing a LLD of greater than 20 mm [1]. Patients suffering from this condition can experience lower back pain, osteoarthritis of the hip, and stress fractures [2–4]. LLD is surgically treated with distraction osteogenesis, in which newly formed bone callus is lengthened after an osteotomy [5]. Surgeons treat LLD’s with both external and implantable devices.

External fixation frames rely on tissue penetrating pins that lead to infection rates as high as 30% [6]. More recently, actuated intramedullary (IM) nails provide greater patient comfort and avoid issues associated with exposed hardware [7]. However, success with IM nails has not yet translated into pediatric orthopedics. IM devices can be difficult to implant in...

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