Influence of cortical canal architecture on lacunocanalicular pore pressure and fluid flow.
Bone is a dynamic tissue that undergoes structural modification in response to its mechanical environment, but how bone cells sense and respond to loading conditions remains incompletely understood. Current theories focus on strain-induced fluid flow for the primary means of mechanotransduction. To examine the influence of age-related cortical rarefaction on lacunocanalicular fluid characteristics, coupled fluid flow and mechanical computational models of bone specimens representing young, mid-age and aged samples were derived artificially from the same original micro-computed tomography image data. Simulated mechanical loading was applied to the bone models to induce pressure-driven interstitial fluid flow. Results demonstrated a decrease in pore pressure and fluid velocity magnitudes with age as a result of increased cortical porosity. Mean canal separation, as opposed to canal size, was implicated as a primary factor affecting age-related fluid dynamics. Future investigations through refinement of the model may implicate fluid stasis or inadequate nutrient transport experienced by osteocytes as a key factor in the initiation of cortical remodelling events.
Schulich School of Engineering, University of Calgary, Calgary, Alta, Canada.
G C
GC
Goulet
D M L
DM
Cooper
D
D
Coombe
R F
RF
Zernicke
D001826:Body Fluids / Q000502:physiology*; D001842:Bone and Bones / Q000502:physiology* / Q000648:ultrastructure*; D003198:Computer Simulation; D006801:Humans; D008954:Models, Biological; D016062:Porosity; D011312:Pressure