Knee buckling may be related to congenital factors, rickets, incorrect walking posture, bone injury and so on. 1. Congenital factors: may be caused by congenital defects, deformities of the lower limbs, the later did not correct in time, which leads to knee buckling. 2. Rickets: mostly seen in infants and young children, caused by the lack of vitamin D and calcium, if not treated in time, it is easy to lead to softening of bones and muscle relaxation, which leads to knee buckling. 3. Incorrect walking posture: It is possible that long-term walking posture is incorrect, the pressure on the knee joints is relatively large, and the weight-bearing is unbalanced, which leads to knee buckling. Knee buckling may also be caused by other reasons, should be timely consultation, identify the causes and take targeted treatment.