[External fixation for the correction of complex deformities : From the classic Ilizarov ring fixator to modern software-driven hexapod fixators].

The history and development of circular fixation is closely aligned with the history of limb lengthening. Gavriil A. Ilizarov not only developed his circular fixator, but he also was the first to research and publish on distraction osteogenesis. Progress and dissemination of the method was initially based on individual pioneers; a standardized nomenclature and annual courses led to a wider dissemination. The introduction of the Taylor spatial frame in 1997 was a game changer. Although various groups had already developed Hexapod-fixators, it was the TSF that hit the market and achieved market presence. After the patent for TSF expired, many companies developed hexapod fixators with various modifications. A new version of the TSF, the Smart TSF, which included an intuitive planning software, was introduced in Baltimore in 2021. The introduction of intramedullary lengthening nails at the beginning of the 2000s and the wide dissemination starting approximately 2013 rendered external fixation obsolete for certain indications. However, ring fixators are still the method of choice for complex reconstruction of deformity in traumatology, as well as in pediatric orthopedics in the presence of open growth plates.