A computational study on electric field-induced canalicular fluid flow in bone tissue

Age-related or postmenopausal osteoporosis promotes bone fracture risk. Prevention and treatment of osteoporotic-associated bone fracture is a major challenge for clinicians and biomedical engineers. Osteoporotic skeleton exhibits diminished new bone response to mechanical stimulation. However, electric field stimulation in combination with mechanical loading is efficacious in case of osteoporosis. Fluid flow through the lacunar canalicular system (LCS) of bone tissue acts as a stimulus for new bone formation. However, the exact mechanism which enhances the fluid motion essential for osteogenesis in response to exogenous electric field remains unclear. Accordingly, this study aimed to determine the uniaxial loading-induced canalicular fluid flow in a complex 2D lacunar canalicular channel under the influence of exogenous electric field. In addition, the optimal input parameters were computed in order to obtain maximum canalicular fluid velocity using response surface methodology (RSM). Results show that the fluid velocity and wall shear stress increases with increase in maximum electroosmotic velocity, electric field parameter, and non-dimensional frequency. In contrast, electric field in combination with mechanical loading modulates the fluid flow- and fluid-induced shear stress in porous bone with pathological conditions as well. The present study also explains how electric fields in combination with mechanical loading possibly modulate mechanobiological stimulus in bone. Based on the outcomes, best loading regimen may be designed in combination with an external electric field to increase bone growth and decrease bone resorption in osteoporosis patients. Moreover, this study offers new insights towards treatment against age-related osteoporosis.