Abstract: Objective Strategy for wound repair of skin and soft tissue defect and systematic rehabilitation treatment for functional reconstruction of patients with severe burn or trauma on knees. Methods From January 2015 to October 2016, 26 patients with skin and soft tissue defect on knees after severe burn or trauma were hospitalized in our unit. Among these patients, 14 patients had patellar ligament defect, and 16 patients had knee joint capsule defect. Wound debridement was operated on 1 to 3 days after admission. After debridement, the area of skin and soft tissue defect ranged from 10 cm×7 cm to 42 cm×18 cm. Vacuum sealing drainage (VSD) treatment was performed after debridement, and flap transplantation operation was performed after VSD treatment for 5 to 7 days. Defects of nine patients were treated with local rotation flaps. Seven patients with skin and soft tissue defects on knees and knee joint capsule defects of 5 cm×3 cm to 9 cm×7 cm were treated with free anterolateral femoral flaps combined with fascia lata. Ten patients with skin and soft tissue defects on knees and patellar ligament defects of 6 cm×3 cm to 12 cm×4 cm were treated with free anterolateral femoral flaps combined with iliotibial tract. The area of flaps ranged from 11 cm×9 cm to 22 cm×15 cm. After flap transplantation operation, functional reconstruction of knee joint was carried out according to early, continuous, and sequential systematic rehabilitation treatment strategy. The pain degree and function of knee joint of patients were scored by the International Knee Documentation Committee (IKDC) Knee Evaluation Form before operation and 12 months after operation. The knee joint flexion and extension degrees of patients were measured by joint protractor in 2 weeks and 12 months after operation. The color Doppler ultrasound was used to evaluate integrity of knee joint capsule and continuity of patellar ligament of patients in 6 and 12 months after operation. Results All flaps of 26 patients survived well, and wounds healed completely after the operation. Distal parts of flaps of 2 patients treated with free anterolateral femoral flaps had local necrosis after the operation, and their wounds healed after debridement and transplantation of autologous intermediate split-thickness skin graft of thigh. The IKDC Knee Evaluation Form score of patients was (79±8) points in 12 months after operation, which was significantly higher than (64±7) points before operation (t=7.20, P<0.05). The flexion degree of knee joint of patients was (117±10)° in 12 months after operation, which was significantly larger than (35±8)° in 2 weeks after operation (t=32.65, P<0.05). The extension degree of knee joint of patients was (12±9)° in 12 months after operation, which was significantly smaller than (61±9)° in 2 weeks after operation (t=19.63, P<0.05). In 6 and 12 months after operation, 9 patients treated with local rotation flaps had good integrity of knee joint capsule and continuity of patellar ligament; 7 patients treated with free anterolateral femoral flaps and fascia lata had good integrity of knee joint capsule; 10 patients treated with free anterolateral femoral flaps and iliotibial tract had good continuity of patellar ligament. During follow-up of 12 months, all flaps survived well; knees of all patients had good appearance; knee joints functioned normally. Conclusions Good appearance and function of knees can be achieved by repairing wound of skin and soft tissue defect on knees after severe burn or trauma with local rotation flaps or free anterolateral femoral flaps with fascia lata or iliotibial tract plus systematic rehabilitation treatment of knee joint in early stage after flap transplantation operation.