The baby’s lateral knee bone protrudes mainly because of a lump on the outside of the knee, which is hard and does not move in the shape of a bone. There are two possible reasons for this: 1. Osteochondroma is a benign bone tumor disease located at the base of the epiphysis of the tibiofibular bone near the knee joint and growing towards the bone surface, also called exophytic bone warts. It is a good idea to consult a regular hospital and evaluate the condition after X-ray and CT to decide whether it is conservative or surgical treatment. 2, tendon sheath cyst, long-term strain or incorrect sports will constantly stimulate the knee joint, resulting in inflammation at the knee joint, wrapped in the wall of the capsule to make it thicken and harden, similar to the symptoms of bone protrusion, usually with a long course of pain. You can choose conservative treatment by giving Loftanzine extended-release tablets to relieve pain, acupuncture and massage, Chinese herbal compresses and other physical therapy to relieve symptoms.