[Clinical efficacy of applying orthoplastic principle in treating Gustilo type ⅢB open ankle joint fractures].

Objective: To investigate the clinical efficacy of applying orthoplastic principle in treating Gustilo type ⅢB open ankle joint fractures. Methods: This study was a retrospective case series study. From January 2018 to August 2024, 33 patients with Gustilo type ⅢB open ankle joint fractures who met the inclusion criteria were admitted to Wuxi Ninth People's Hospital, including 25 males and 8 females, aged 25-65 (44±12) years. The area of skin and soft tissue defects ranged from 6 cm×3 cm to 27 cm×14 cm. The length of bone defect ranged from 3.0 to 9.2 cm (with mean of 3.7 cm). All patients were treated based on the orthoplastic principle. Phase Ⅰ-Stage 1: after thorough debridement was performed in emergency department, antibiotic bone cement was inserted in the tibial defect, an external fixator or an antibiotic bone cement-coated steel plate was applied for temporary stabilization. Nerves and tendons were repaired, and the remaining wound was covered with vacuum sealing drainage dressing. Phase Ⅰ-Stage 2: on days 3 to 7 after injury, the wound was debrided again, and the antibiotic bone cement was replaced. The internal fixation was adjusted or retained according to the fracture status, and an anterolateral thigh flap (with size ranging from 7 cm×3 cm to 30 cm×15 cm) was designed and harvested to repair the wound. A stepwise strategy was employed for treating the donor site wounds based on the defect size and local tension. For wounds with low tension, primary closure was performed. For wounds with high tension, the wound edges were appropriately pulled together during operation, and either direct closure or split-thickness skin grafting from the opposite thigh was carried out after the postoperative edema subsided. Phase Ⅱ-Stage 3 (the only stage): 7 to 30 weeks after injury (with mean of 15.8 weeks), the antibiotic bone cement was removed, the volume of bone defect was measured, and the iliac crest bone was harvested precisely, mixed with vancomycin, and used to fill the bone defect; the induced membrane and skin soft tissue were then sutured. Postoperative flap survival and infection-related complications at different stages were recorded. During follow-up, flap appearance and texture, scar condition at the donor and recipient sites, and bone healing were documented. At the last follow-up, the affected foot function was assessed using the foot and ankle ability measure (FAAM) scale, and the percentage of recovery in daily living ability was calculated. Patient health outcomes were assessed using the 36-item short form health survey (SF-36), and the scores of the physical component summary (PCS) and mental component summary (MCS) were calculated. Results: Complete flap survival was achieved in 30 patients after operation. Partial flap necrosis occurred in 3 patients, among whom 1 case healed by direct suture after debridement, and 2 cases healed by skin grafting after debridement. Infection-related complications occurred in 4 patients, including superficial infection in 3 cases (1 case after Stage 2 in Phase Ⅰ, 2 cases after Stage 3 in Phase Ⅱ), all of which were controlled after debridement with wound healing. Bone infection occurred in 1 case (after Stage 2 in Phase Ⅰ), which was controlled after repeated thorough debridement and antibiotic bone cement packing, and bone grafting healed. The follow-up period ranged from 12 to 57 months (with mean of 26.7 months). All flaps showed good color and texture. Scar hyperplasia at the flap donor site occurred in 3 cases, while only linear scars remained at the recipient site. At final follow-up, the FAAM scale score of the affected foot was 71±4, and the recovery of daily living ability reached (85±5)%. The PCS score on the SF-36 was 78±4, and the MCS score was 70±11. Conclusions: Applying the orthoplastic principle for treating Gustilo type ⅢB open ankle joint fractures results in low infection and other complication rates, along with satisfactory functional recovery of the ankle joint.