In Borovia, they have a saying: The wall mustn’t fall. So they toil day and night, dismantling their museums, monuments, and edifices for stones to build the wall.
In Morovia, they have a saying: Prosperity comes from the infinite stone heap. So they salvage the rocks day and night, constructing museums, monuments, and edifices.
Generation by generation the wall crept forward, until the day Borovia ran out of rocks and ran out of Borovia. The wall fell, and the Morovians beheld the source material of their civilization.
“Barbarians!” they shouted. “Quick, someone get a wall up before they invade Morovia!”
Call this story my attempt to channel Dr. Seuss, who in spite of his name, did not actually have a doctorate. This is a story about equilibrium between opposing forces. Specifically, I wrote it to illustrate the delicate balance between osteoblasts, the cells that form new bone, and osteoclasts, the cells responsible for dissolving bone.
Bone remodeling is the ongoing process in your body of shaping, repairing, and adjusting your bones. A great deal of bone remodeling happens during puberty when your bones lengthen to their adult size. But even as adults, our bones grow and change throughout our lives. Part of this is in response to stress, such as participating in high-impact sports like soccer, basketball, or running. Even milder stresses, such as using crutches for a long period of time, will cause changes in your bone structure. Also, adult bones naturally expand in width throughout our lives.
While our bones may grow, they do not actually thicken. Most bones contain a hollow cavity filled with bone marrow. Osteoclasts line the inside of the cavity and dissolve the bone. Think of them like the Morovians, tearing down the stone wall piece by piece. At the same time, osteoblasts use extra calcium in your bloodstream to build new bone on the outer surface. They are like the Borovians, piling up materials to keep the wall high. If all is well, the two forces are in equilibrium. The bone grows over time but maintains a uniform thickness.
Bones that are too thick or too thin cause a wide variety of health problems. For example, osteoporosis results from unusually thin or porous bones. Osteoporosis can develop for several reasons, but generally it happens when the osteoclasts are dissolving bone too quickly or the osteoblasts are building it too slowly. The bone grows thin and is more likely to break under stress.
So there you have it: the Borovians and Morovians are both right. The wall mustn’t fall, and the scavenging mustn’t stop. Otherwise bad things happen.
And I don’t mean barbarian invasions.