[Organizing diagnosis of parameters of limb loading during transosseous osteosynthesis by external fixation devices]

The presented system for compression-traction osteosynthesis (CTS) involves a modified Ilizarov apparatus, a set of force and length detectors, PC controlled measuring system, a set of cables and original software. The system apparatus allows for angular displacement of bone fragments in the range of +/- 30 degrees or 0-60 degrees and lateral displacement of bone fragment edges in the joint along any azimuth in the ring plane. It was mathematically proved that the axial and angular displacement of the two apparatus ring blocks relative to each other can be described with three parameters: axial displacement of the ring center, the ring deflection (turn) angle and the ring axis turn azimuth (angle). Formulas for calculation of the displacement of three pairs of displacement control nuts so the plane of the fracture displacement angle (correction) cross the axis of the required ring plane turn azimuth (angle) were deduced for the reciprocal angular displacement of the bone fractures. No additional removable joints or the apparatus reconstruction for angular fracture displacement are needed. The CTS features the display of the current reciprocal position of bone fragment axes during the course of apparatus loading on the PC monitor.