Resumption of School After Lockdown in Covid-19 Epidemic: Occult Fracture on the Same Site of the Same Grade Adolescents

Background: ： As the capital city of Hunan Province next to Hubei Province very closely, Changsha started Level 1 response of major public health emergency on January 23. After 75 days of lockdown due to Covid-19 epidemic, students in the 9th grade of junior high school started hard training for physical entrance examination. Case Presentation： We report three cases of occult fracture on the same site in adolescents of the same grade since resumption of school after lockdown in covid-19 epidemic. Three students in the 9th grade of junior high school who were facing the physical examination in two weeks are diagnosed the occult fracture of the distal femur. Conclusion： It is recommended that the students, parents, education providers and policy makers should all pay attention to the physical exercise of students that should be from a small amount to a medium amount and then to examination training. The sudden increase in the amount of exercise may cause hidden fracture of young people.