Congenital leg inequality can be seen in childhood, but it can also be seen due to subsequent accidents and bone infections. Congenital limb is often unrecognized until 6 months of age. Some may be confused with hip dislocation. In general, leg length inequality can be divided into congenital, developmental and acquired causes. Examples of congenital causes include congenital femur deficiency (such as proximal femur deficiencies), fibula deficiency, tibia hemimelia, hemimialomeningocele, idiopathic, hemiatrophy or hemihypertrophy.

Developmental causes may also cause leg length inequality. Some of those; melorheostosis, congenital distorted foot, enchondromatosis, osteochondromatosis, neurofibromatosis. Acquired causes include fracture-related growth disorder, infection, radiation, and other causes. (Blount’s disease, Perthes disease, post-fracture malunion and inflammatory arthritis).