Characteristics of proximal tibial epiphysis structure and effectiveness of impression fragments fixation in tibial 57 condylar fractures (in vitro study)

The structure of cancellous bone of the proximal tibial epiphysis using CT and measurement of Leeb hardness was investigated. The author found that subchondral layer as thick as 10 - 15 mm which corresponds with the thickness of impressed fragments of tibial condylar fracture has the density and elasticity modulus up to 84,4% of lowest threshold value of the compact bone. In more deep layers from cartilage the cancellous bone progressively loose it’s density and hardness and deeper than 40 mm they reach their lowest threshold value. Higher level of plating with screwing through impression fragment can persist significantly more (p<0,05) cyclic loading (24066±2015) even without bone grafting, than the same fixators inserted lower with deeper than 20 mm screwing through the bone graft (2133±446 cyclic loading). Such application of the plate with passing screws through subchondral layer of impression fragments at the level of 5-7 mm from joint cartilage can be achieved by anatomic preoperational pre-bending of any fixator.

плотность и твёрдость губчатой кости, фиксация импрессионных фрагментов, переломы мыщелков большеберцовой кости, density and hardness of cancellous bone, fixation of the impression fragments, tibial condylar fractures