Cortical Bone Porosity — RANKL/OPG Remodeling Imbalance

This simulation zooms into a block of cortical bone and models the cellular process that actually causes osteoporosis: not a single "bone loss event," but thousands of independent Basic Multicellular Units (BMUs) each drilling and refilling a Haversian canal. An osteoclast cutting cone widens a canal, then an osteoblast closing cone narrows it back — and the RANKL/OPG ratio slider controls how deep each cut goes and how much the refill lags behind it. Push the ratio up (mimicking postmenopausal estrogen loss or chronic kidney disease-related bone disorder) and canals stop fully closing, so cortical porosity climbs year over year; add an antiresorptive dose and watch the same BMUs swing back toward balance. Live readouts track porosity, simulated years, active BMU count and the net micron balance per remodeling cycle.