ARTHRITIS IS NO LONGER YOUR GRANDPARENT'S DISEASE. DOCTORS ARE SEEING YOUNGER PATIENTS COME INTO THEIR OFFICES WITH STIFFNESS AND JOINT PAIN. WHY IS THIS HAPPENING? PRO ATHLETES LIKE PETE ROSE, KEN GRIFFEY AND LEBRON JAMES KNOW INJURY IS JUST PART OF THE GAME. BUT WHEN TODD BONNELL WAS PLAYING HIGH SCHOOL BASKETBALL, HE COULDN'T HAVE IMAGINED HOW AN INJURY WOULD CHANGE HIS LIFE. "Well, my senior year in high school, I started with the torn meniscus at the beginning of the year." BY THE TIME HE WAS IN HIS EARLY TWENTIES, DOCTORS SAID HE HAD ARTHRITIS. "We just had the MRI and saw the arthritis, I guess." TODD UNDERGOES EXTENSIVE PHYSICAL THERAPY. DOCTORS SAY HE'S NOT ALONE. "What we're seeing now is more secondary arthritis, and that's arthritis due to injury, athletic injury and/or athletic injury and surgical procedures." ORTHOPEDIC SURGEON TIM KREMCHEK SAYS OSTEO-ARTHRITIS IS THE MOST COMMON FORM OF ARTHRITIS, AND IT'S EXPLODING IN YOUNG PEOPLE. "I've seen children under the age of 10 that have had traumatic arthritic changes, yes." ONE STUDY FOUND NEARLY 70-PERCENT OF A-C-L INJURIES IN YOUNG ATHLETES WILL LEAD TO EARLY OSTEO-ARTHRITIS. CAUSES INCLUDE JOINT OVERUSE, POOR TECHNIQUE AND IMPROPER USE OF EQUIPMENT. PHYSICAL THERAPY IS A COMMON TREATMENT. BUT INCREASINGLY, DOCTORS ARE USING INJECTIONS TO LUBRICATE THE JOINTS AND A SURGICAL PROCEDURE CALLED ARTHROSCOPY. "And, that's making two small little poke holes and arthroscoping, cleaning out the knee." DOCTOR KREMCHEK SAYS THE IDEA IS TO HELP YOUNG PEOPLE MAINTAIN THEIR ACTIVE LIFESTYLES. TODD SAYS GOLF CAN HURT HIS KNEES MORE THAN BASKETBALL, BUT HE ISN'T WILLING TO GIVE UP EITHER YET. HE'S TOO YOUNG. DOCTOR KREMCHEK SAYS THERE'S NO CURE FOR ARTHRITIS, AND JOINT REPLACEMENT IS AN ABSOLUTE LAST RESORT FOR YOUNG PATIENTS. HE BELIEVES A COMBINATION OF PHYSICAL THERAPY, ANTI-INFLAMMATORIES, INJECTIONS AND SOMETIMES SURGERY ARE THE BEST OPTIONS.