[Three-dimensional planing and correction of osteotomies in the forearm and the hand].

New 3-dimensional supported technologies considerably improved accuracy of corrective osteotomies and allowed alignments of cuts not possible before. The introduction of simply applicable software made it possible also for not in informatics educated persons to segment CT data, generate 3D models of bones and compare them with the mirrored opposite side. Only this approach allows an exact analysis of deformation, the creation of an operation plan and the virtual performance of the procedure in 3D. The production of individualized drilling and sawing guides which fit defined and unique to the bone surface by laser sintering technique permits an exact implementation of the planning to the operation. The technique is presented on the basis of cases of the forearm and hand.