The best of all is written by wikipedia, especially if you are better reading than writing.
Actually Ilizarov's method us using osteotomy - is a surgical operation whereby a bone is cut to shorten, lengthen, or change its alignment. So it is used at Ilizarov's technique of course.
There is also "incomplete" osteotomy or corticotomy used at Ladisten Clinic for bowed legs correction, this is a "cutting of the bone that splits it in two (bone fracture) but involves cortex only, leaving intact the medullary vessels and periosteum. Corticotomy is particularly important in distraction osteogenesis" used for deformities correction and limb lengthening.
Let me know if this helps.
Thank you so much for your comment
The basic idea behind osteotomy is correction of the position of the bone. If your leg bones are bowed due to incorrect positioning, it may help. But if they are bowed through the body, Ilizarov's technique is good.