Sciatic and tibial nerves and a femoral osteotomic area were investigated in experiments on 36 adult mongrel dogs during neutral and distractional osteosynthesis. Histological and X-ray studies, computer-assisted image analysis, and statistical methods were used. The morphological basis of hemodynamic features of the nerves and long tubular bones was characterized. The mechanisms responsible for perivascular osteogenesis in the bone marrow cavity and for hypertrophy of perineural cell paravasal spongy structures in the nerves were studied as compensatory and adaptive responses to changes in the hemodynamical components of homeostasis after bone injury and during extremity stretching.