Mostly seen in the extreme stage of rickets activity and sequelae period: ① head cranial softening is mostly seen in infants from 3 to 6 months old, with the occipital bone or parietal bone as obvious, the cranial bone sunken when finger pressure is applied, and regains its original shape when the pressure is removed (such as the feeling of ping-pong balls); after 6 months, the cranial bone growth rate slows down, manifesting as the frontal bone and parietal bone bulging into a square cranium. There may also be late closure of fontanel, late teething, etc. ② blunt rounded elevation at the junction of rib and rib cartilage on both sides of the chest called “rib beads”, the 7th to 10th rib is significant; rib softening, rib sunken to form a transverse groove; severe rickets sternum protrusion to form a chicken chest. Most often seen in infants aged 6 months to 1 year. The spine and limbs can be bent forward and backward or laterally, and the wrists and ankles are inflated like “bracelets” and “ankle bracelets”; after 1 year of age, the child starts to walk, and the long bones of the lower limbs are bent in an “O”-shaped or “X”-shaped manner due to weight bearing. “X” shaped legs. If early light rickets can be treated in time, it can be completely recovered without leaving deformities. Severe rickets can leave skeletal deformities of varying severity, such as square skull, chicken chest, “O” or “X” shaped legs, mostly after the age of 3.