Knee varus, commonly known as "O-leg", "bow leg" and "basket leg". When the lower limbs are naturally straight or standing, the medial malleolus of both feet can touch each other, but the knees cannot be brought together, which is the main manifestation of deformity. You can try autologous fat O-leg correction. Song Wenbin, director of Yayun Plastic Surgery, has achieved good results in this respect.