What Is the Motion Across the Fracture Line?

The reason bones heal is because there is motion across the fracture line, which acts as cell signalling to secrete bone mineral and heal the fracture. A fractured rib heals in about three weeks. That's why they never stop moving. And i know this to be true because, oh, about 20 years ago, a, my girl friend got in a real, real bad wreck, and got tea boned at about forty miles an hour by a guying a truck,. She was really, really badly fucked up. Her chest x ray, after nine months, was normal. It only took nine months. Why is that? Cause they never stopped moving.