Résumé
BACKGROUND:Establishing an objective and standard animal model of bone nonunion is essential for experimental studies and treatment of nonunion. OBJECTIVE:To establish an objective animal model for experimental studies of nonunion. METHODS:Specific pathogen-free male Wistar rats were selected and prepared by cutting off a 5 mm bone defect in the middle femur,peeling off a large periosteum and removing bone marrow.Animal models were fixed with a 1.2 mm Kirschner wire.At 1,4 and 8 weeks,bone nonunion was observed by gross specimen observation,X-ray examination and histopathological examination. RESULTS AND CONCLUSION:The gross specimen,X-ray film and histopathological examination showed that there was no callus formation in the bone defect area,the broken end was filled with fiber tissue,and the bone callus was rare or even invisible.To conclude,the rat model of nonunion can be successfully established by osteotomy of the middle femur,large periosteum peeling and bone marrow removal.This modeling method is simple,reliable and effective.
Résumé
Objective:To explore the curative effect of wide pedicled with double-vessel flap of posterior lateral calf in repair of soft tissue defect in hind foot.Methods:From January 2018 to June 2021, 12 patients with soft tissue defects on hind foot were reconstructed with double-vessel flaps pedicled perforator of peroneal artery and sural nerve nutrient vessels in the Department of Trauma Orthopaedics, No.940 Hospital of Chinese People's Liberation Army Joint Service Support Force. The patients were 8 males and 4 females, aged 9-45(27.17±12.14) years old. Time after injury to admission was 6-24(10.17±4.80) hours. Six patients were with simple soft tissue defects, 2 with tendon defects, 3 with bone defects and 1 with postoperative infection due to an open fracture. The sizes of soft tissue defect ranged from 4 cm×5 cm-8 cm×12 cm. Soft tissue defects were reconstructed by transfer of posterolateral calf flaps, and the bone defects were repaired by phase I or phase II bone grafts or antibiotic cement and membrane induction according to the wound surface. For larger bone defects, stage-II bone transport was carried out to restore the length of the hind foot. Defects of Achilles tendon were reconstructed by direct suture or tendon transposition. Foot functions were evaluated by American Orthopaedic Foot and Ankle Surgery(AOFAS) ankle-posterior sufficient scale, visual analogue scale(VSA) score and flap healing. All patients were included in postoperative follow-up regularly through outpatient clinic or via WeChat.Results:All 12 patients had postoperative follow-up that lasted for 6-24(12.92±6.22) months. One flap developed dark purple colour with swelling at the distal end of the flap 3 days after surgery. It eventually healed after removed some sutures from the pedicle together with blood-letting on the flap surface. Three flaps developed local infection, and they were cured after debridement, dressing change and the use of sensitive antibiotics. The remaining 8 patients had achieved good appearance of flaps and normal ankle function. According to AOFAS, scores of ankle-posterior sufficiency scale increased from 14-45(25.25±5.42) before surgery up to 65-96(75.92±7.73) at the final follow-up. Of the 12 patients, 8 were in excellent, 2 in good and 2 in fair. The VAS scores decreased from 5-8(6.55±1.13) before surgery down to 0-4(1.55±1.37) at the final follow-up. The difference had statistics significance( P<0.01). All patients had satisfactory recovery of ankle function, with the extension at 15-20 degrees and plantar flexion of 30-40 degrees. The donor site healed well and all skin grafts survived. Conclusion:The double-vessel flap pedicled with perforating branch of peroneal artery and nutrient vessels of sural nerve can be used for reconstruction of soft tissue defect of hind foot. It achieved good surgical effects with reliable blood supply, smooth venous return, strong anti-infection ability, satisfactory appearance at donor site and flap itself, as well as a good recovery of foot function.