"That's because you're growing." The people who told him that as a child when he complained of joint pain were probably right: growing up often hurts. "Growing pains exist and, in fact, are one of the most frequent causes of musculoskeletal pain in childhood," points out Dr. Anna Pujol Manresa, a rheumatologist in the pediatric department of the Germans Trias Hospital in Badalona and a professor at the Autonomous University of Barcelona (UAB) in the Can Ruti Campus teaching unit. "However, it's not directly related to bone growth," she clarifies.