RESUMEN
Objective:To investigate the efficacy of digital reconstruction technology in assisted design of lobulated deep inferior epigastric perforator flap (DIEPF) for surgical reconstruction of large defect in lower extremity.Methods:From January 2017 to January 2022, a study was carried out to retrospectively analyse 8 patients who had massive soft tissue defects in lower extremities were admitted in the Department of Orthopaedic Surgery of the 920 Hospital of Joint Logistic Support Force of Chinese PLA. The size of defects varied from 16.0 cm×12.0 cm-28.0 cm×22.0 cm. CTA scans were performed over abdominal aorta and the arteries of lower extremities. Three-dimensional model of DIEPF and vascular pedicles were reconstructed by Mimics software. According to the shape and size of the wound, targeted perforators were determined on the 3D images, and precisely mapped in a digitised rectangular coordinate system. The lobulated flap was then digitally designed in the 3D coordinate system. Flaps were harvested according to preoperative digital designs for the reconstruction of large defects in the lower extremities. The donor site was sutured directly. The flaps and recovery of lower extremities were observed though postoperative follow-ups and were conducted through visits of outpatient clinics and distance interviews via telephone and WeChat. Recoveries of lower extremities were evaluated using Maryland ankle-foot function scoring system.Results:The 3D reconstructed models of the vessels in donor sites were successfully completed for all patients. The harvests of lobulated DIEPF were successfully guided by the digital designs. Fifteen lobes of lobulated DIEPF survived successfully in all 8 patients. All donor sites were closed in the stage-I. Necrosis occurred at the distal tip of a lobulated flap due to a local venous occlusion, and healed after debridement and re-suture. Four patients received further flap debulking surgery. Time of postoperative follow-ups had ranged 15-27 months, with an average of 20 months. At the last follow-up, all the flaps had satisfactory appearance with linear scars at the donor sites. All fractures were healed. Five patients achieved Maryland's ankle-foot function score in excellent, 2 in good, and 1 was acceptable.Conclusion:Digital reconstruction technology can accurately map the perforators and reasonably assist the design of lobulated flaps. A lobulated DIEPF offers a wider area for flap excision and allows a primary closure of the donor sites. Combination of the 2 advantages of a lobulated DIEPF can be effectively applied in reconstruction of a large-sized defect in lower extremity.