Some forms of chronic pain are particularly mysterious 

When she was only 14, Catherine Charlwood noticed a swelling in her right forearm. It was accompanied by a heavy muscular ache that made daily activities difficult. As a talented clarinettist at a British school where regular practice was on the timetable, the pain was deeply worrying. She was told it was repetitive strain injury, and would disappear within six weeks. When those weeks had gone and the pain remained, she was diagnosed with tendonitis. She did her best to make do, minimising her music practice and learning to write with her left hand. Eventually, when playing the clarinet was no longer feasible, she had to leave the school.