Physorg.com -- Every day the world over, runners hit the streets, pounding the pavement. Their knees are taking a pounding, too. As runners well know, cartilage, the shock absorber within the joint, wears down over time and when an injury occurs, it is unable to heal itself. Traumatic injury can cause small tears on the cartilage surface that never heal, and get worse with time. Trauma and arthritis are the primary culprits for sidelining jogging enthusiasts and weekend warriors alike.
