Fracture healing in biological plate osteosynthesis

In order to gain a better understanding of the healing processes after plat e fixation and indirect reduction, Baumgaertel designed a reproducible frac ture model for the sheep femur in 1992 so that the differences between anat omical (rigid) and biological (bridging) fixation could be investigated. It was demonstrated that indirect reduction and bridge plating was superior t o direct fragment reduction and anatomical fixation in respect to radiology , biomechanics and microangiography. in this study, it was shown that bony bridging of the fracture gap and mineralization of callus occurred faster a nd more efficiently after indirect than after direct and anatomical reducti on. Bone healing was identified as beginning in the 2.-3. week after indire ct and only in the sixth week after direct reduction. The increased breakin g strength of the indirectly reduced femora at 8 weeks can be attributed to this process. In addition, the consequences of applying the PC-Fix for bio logical plating were investigated. The values for bone healing were improve d by applying a plate with only point contact to the bone, thus conserving the periosteal blood supply.