Objective To explore the clinical treatment of incisional wound infection after orthopedic internal fixation for lower extremity joint injuries. Methods A retrospective cohort study was conducted. From February 2014 to December 2019, 214 patients with lower limb closed injury were treated in Beijing Jishuitan Hospital, including 143 males and 71 females, aged from 16 to 65 years. All patients underwent orthopedic internal fixation, after which incisional wound infection developed in 42 cases of postoperative wounds of patellar fracture, 30 cases of postoperative wounds of tibial plateau fracture, 72 cases of postoperative wounds of Achilles tendon rupture, 45 cases of postoperative wounds of calcaneal fracture, and 25 cases of postoperative wounds of Pilon fracture with 31 cases of superficial infection and 183 cases of deep infection. According to the postoperative evaluation of the incisional wounds, dressing change and/or thorough debridement (with wound area from 4 cm×3 cm to 11 cm×5 cm after debridement), and internal fixation treatment were performed. After thorough debridement, wounds were treated with continuous vacuum sealing drainage (VSD), and then direct suture+VSD or flap transplantation were performed according to the incision and its surrounding skin tissue, infection, suture tension, exposure of internal fixation or bone or Achilles tendon tissue. According to the wound site and injury, the flap types of retrograde anterolateral thigh perforator flap, medial sural artery perforator flap, gastrocnemius myocutaneous flap, sural neurovascular flap, peroneal brevis muscle flap, posterior tibial artery perforator flap, and free anterolateral thigh perforator flap could be selected. The donor site wound was closed by direct suture or grafted with split-thickness skin graft. The removal of internal fixation, wound repair method, type and size of flaps, survival of flaps, and wound healing were recorded. The recurrence of infection, appearance of donor and recipient areas, and recovery of lower limb joint function were followed up. Results All the internal fixations were removed in patients with postoperative wounds of patellar fracture, among whom 36 cases were repaired with retrograde anterolateral thigh perforator flap, and 6 cases were repaired with medial sural artery perforator flap. Among the patients with postoperative wounds of tibial plateau fracture, the internal fixation was completely retained in 18 cases, partially removed in 6 cases, and completely removed in 6 cases, while the wound was closed by direct suture in 8 cases, transplanted with gastrocnemius myocutaneous flap in 21 cases, and transplanted with medial sural artery perforator flap in 1 case. Among the patients with postoperative wounds of Achilles tendon rupture, the internal fixation was completely retained in 10 cases and completely removed in 62 cases, and the wound was closed by direct suture in 10 cases and transplanted with sural neurovascular flap in 62 cases. Among the patients with postoperative wounds of calcaneal fracture, the internal fixation was completely removed in 32 cases and completely retained in 13 cases, and the wound was healed by dressing change in 5 cases, closed by direct suture in 5 cases, transplanted with sural neurovascular flap in 23 cases, and transplanted with sural neurovascular flap combined with peroneal brevis muscle flap in 12 cases. Among the patients with postoperative wounds of Pilon fracture, the internal fixation was partially removed in 5 cases, completely retained in 17 cases, and completely removed in 3 cases; the wound was closed by direct suture in 4 cases, transplanted with posterior tibial artery perforator flap in 18 cases, and transplanted with free anterolateral thigh flap in 3 cases. The area of flaps/myocutaneous flaps ranged from 5 cm×3 cm to 18 cm×8 cm, and the area of muscle flaps were from 13.0 cm×1.5 cm to 15.0 cm×2.5 cm. All the wounds closed by direct suture healed. Blood flow obstacle occurred in the distal margin of sural neurovascular flap transplanted in 5 patients and posterior tibial artery perforator flap transplanted in one patient, which healed successfully after dressing change. The other flaps survived well, and the wounds were healed. The patients were followed up for 5 months to 5 years, and no recurrence of infection occurred. The direct suture of the flap donor site left linear scar, and the appearance of the skin graft was good. Three patients with tibial plateau fracture and 2 patients with Pilon fracture had limited joint movement, while the joint activity of the other patients was normal. The patients with Achilles tendon rupture and calcaneal fracture had normal ground motion. The sural neurovascular flap grafted on the wound after calcaneal fracture was bloated resulting in inconvenience in wearing shoes, the gastrocnemius myocutaneous flap grafted on the postoperative wound after tibial plateau fracture was bloated, whereas the appearance of the other flaps was good. Conclusions For incisional wound infection after orthopedic internal fixation for lower extremity joint injuries, the treatment should be classified according to wound infection and wound site. Dressing change, thorough debridement, reasonable disposal of internal fixation, direct suture after application of VSD, and flap covering, etc. not only ensure the infection control and the wound closure, but also restore the function of the lower limbs to the greatest extent, so as to maximize the benefit of the patient.