In the clinic, we find that many patients with burns on both lower extremities find that their legs are not straight after the trauma heals, so we need to do some special rehabilitation training, such as joint loosening, joint loosening training for knee and ankle joints to help straighten them, and we can also fix the joints with braces to correct the flexion deformity. In fact, after the burns, the lower limbs are not straight for the following reasons: 1, scarring: most of the scarring is in the popliteal fossa, scarring is characterized by centripetal contracture, the scarring in the popliteal fossa will pull the knee joint is flexion deformity, resulting in leg extension is not straight; 2, the trauma is not healed: in bed may brake for a long time, after braking for too long, the soft tissue around the knee joint will contract, resulting in flexion deformity of the knee joint deformity. No matter which cause the leg is not straight, rehabilitation training should be done. In addition to joint loosening training or brace correction training by professional rehabilitation therapists, patients can also do anti-contracture therapy by leg compression and leg extension to promote the early straightening of the leg.