Some pathomechanic's aspects of intraarticular bone impression fractures

The human trabecular bone’s strength properties in periarticular localization under uniaxial compression were studied. Male ( N = 24, 60.0%) and female ( N = 16; 40.0%) bone cadaver specimens were studied, average age was 39.5 ± 5.6 years. Proximal tibia ( N = 40), distal radius ( N = 40) and the calcaneus bone ( N = 40) were evaluated. We used physical, morphometric, morphological methods, computer tomography, scanning electron microscopy, statistical analysis. Samples were deformed to a maximum stress of ~ 30%. Maximum value of stresses for the calcaneus bone was 2.06 times higher than for distal radius ( p = 0.012) and 2.09 times to proximal tibia ( p = 0.025). Young’s modulus for proximal tibia was 2.2 times greater than for distal radius ( p = 0.004) and 2.7 times to proximal tibia ( p = 0.024). The physical density for distal radius was 0.936 ± 0.073; for proximal tibia - 0.912 ± 0.097; for the calcaneus bone - 1,092 ± 0,092 g/mm3. Radiodensitometric density for distal radius was 204.9 ± 7.2 HU (Hounsfield unit); for proximal tibia - 256.0 ± 7.0; for the calcaneus bone - 318.0 ± 3.0 HU. There was an increase in mechanical properties with an increase in physical density ( r = 0.678, p = 0.002) and radiodensitometric density ( r = 0.508, p = 0.012). Impression deformation arising from intraarticular fractures characterizes trabecular bone tissue as an elasto-plastic material, the destruction of which does not occur even after reaching a deformation of 30% or more from the height of the sample, with a reversible deformation of 3%. Young’s modulus, maximum stress, elastic deformation, radiodensitometric and physical density of the trabecular bone tissue of the periarticular localization are the criteria of bioequivalent choice of bone graft material to eliminate the structural defect.