[Spectrum of indications for intramedullary or external fixators for axis correction and limb lengthening].

Corrective osteotomy is a well established operative option for correction of predominantly congenital skeletal deformities on the growing skeleton. The indications for the use of a suitable corrective instrument result partly from the location, severity of the deformity and the presence of concomitant leg length discrepancies. External fixators are predominantly used for correction of combined deformities. For isolated leg length differences limb lengthening nails can be implanted but only after growth plates have become closed; however, only a few combined deformities can be addressed in this way. Often several surgical steps are necessary. A careful treatment plan can only be created if the analysis of the deformity is carried out with appropriate parameters and a correct prognosis of the further development. The aim of this paper is to describe the indications for the corrective instruments, the planning of corrections and the presentation of typical indications for axis correction and limb lengthening.