Physiological loading-induced streaming potentials in osteogenesis imperfecta bone

Abstract

Mechanical loading on bone generates streaming potentials (SPs) and streaming currents (SCs) in lacunar-canalicular fluid which act as stimuli to bone cells namely osteocytes. It is observed that both lacunar and vascular porosity significantly affect streaming potentials and thus the bone remodelling activities. Increased porosity levels associated with bone disorders such as especially osteogenesis imperfecta (OI) and osteoporosis considerably reduce SPs which may further negatively affect bone’s mechanoregulation. This could also be a possible reason for reduced mechanosensitivity of OI and osteoporotic bones to exogenous mechanical stimulation. There is hardly any work in the literature which explored the physiological loading induced SPs and SCs in healthy versus OI bone. Accordingly, the present study attempts to address the two important questions: (i) how does physiological gait loading generate SPs and SCs in Healthy versus OI osteons? (ii) Can mechanical and electrical stimuli be effectively utilised to enhance SPs and SCs in OI bone? A transversely isotropic-poroelastic osteon model is developed to compute SPs and SCs in interstitial fluid flow in response to exogenous mechanical and electrical stimulations. The outcomes indicate that streaming potentials and current significantly decrease in OI bone, whereas, loading frequency and electrical field has potential to enhance SPs and SCs in OI bone. The present study concludes that physical exercises in presence of external electrical stimulation may potentially enhance SPs and SCs in interstitial bone fluid to improve remodelling activities OI bone for naturally strengthening.