Abstract: Objective To observe clinical efficacy of using free anterolateral thigh flaps with iliotibial tracts in repairing skin and soft tissue defects around the knee joints with patellar ligament defects. Methods Twelve patients with skin and soft tissue defects around the knee joints and patellar ligament defects were hospitalized from June 2010 to June 2014. The defects of skin and soft tissue ranged from 7 cm×6 cm to 16 cm×12 cm in area, and patellar ligament ranged from 5 to 12 cm in length and 2.5 to 4.0 cm in width. Free anterolateral thigh flaps with iliotibial tracts were used to repair these defects. During reconstruction of patellar ligament, both ends of iliotibial tract were successively folded to form tendon-like three-layer structure at first, and then the newly formed structure was wrapped around the broken ends of patellar ligament and fixed with suture. The flap size ranged from 9 cm×8 cm to 18 cm×14 cm. The iliotibial tract ranged from 7 to 14 cm in length and 8 to 12 cm in width. The donor sites were closed by grafting with autologous split-thickness skin harvested from thigh or trunk, and parked with gauze. Immediately after operation, the knee joints were fixed in extension with orthosis for 6 weeks. Weight bearing training of affected limbs being kept in extension position was started from 2 weeks after operation, and flexion and extension exercise of affected knee joints was begun from 6 weeks after operation. Before operation and 12 months after operation, the degree of pain around the knee joints and knee joint function were evaluated with the international knee documentation committee knee uation form, and the ranges of flexion and extension of knee joints were also evaluated. The integrity of reconstructed patellar ligament was assessed by color Doppler ultrasound from 6 to 12 months after operation. The occurrence of surgery-related complications was observed in all patients within 12 months after operation. Results (1) After operation, all flaps survived well, and all wounds healed well. (2) The average score of pain around the knee joint was increased from 31 points before operation to 77 points in 12 months after operation. The average score of knee joint function was increased from 14 points before operation to 65 points in 12 months after operation. Before operation, the average ranges of flexion and extension of knee joint were respectively 89° and 65°, and they were respectively increased to 130° and decreased to 15° in 12 months after operation. From 6 to 12 months after operation, color Doppler ultrasound showed that the condition of reconstructive patellar ligaments in all patients was good without the need for further surgical intervention; the superficial sensation of the flaps was recovered in different degrees. No surgery-related complication was observed in all patients within 12 months after operation. Conclusions Free grafting of anterolateral thigh flap with iliotibial tract is an effective and reliable method for repairing skin and soft tissue defects around the knee joints combined with patellar ligament defects, and the surgical procedure can recover function and appearance of knee joint satisfactorily.