There are several possible reasons for a bulging kneecap: 1. congenital dysplasia, if a child is born with a developmental deformity it may cause the bones of the kneecap to turn out, this is a normal physiological phenomenon, there will be no symptoms and no treatment is needed. 2. osteochondroma, if long-term strain or other reasons, it may lead to the growth of chondroma in the kneecap. Chondromas are benign tumors and usually have no symptoms, if there is pain, swelling and other symptoms symptomatic treatment can be done. 3, patellar dislocation, if the external impact or fall may lead to patellar dislocation, thus making the kneecap bulge. In this case, you need to consult an orthopedic clinic immediately, and after the manual repositioning, give a cast to fix the brake, and at the same time, you can give Siwei Pu to relieve pain, pulse blood Kang to activate blood stasis, as well as towel hot compress, Chinese medicine paste, Chinese medicine fumigation, Chinese medicine cupping and other physical therapy to relieve symptoms.