ABSTRACT
Objective:To evaluate the effect and mechanism of bone regeneration in distraction osteogenesis zone after the repair of sciatic nerve in rats.Methods:Between January 2021 and August 2021, 60 healthy adult male Sprague-Dawley rats were divided randomly into 3 groups: Group A, B, and C. In groups B and C, right sciatic nerve transection and anastomosis were performed. Then after 8 and 12 weeks, the 3 groups were treated with extension external fixation (Ilizarov technique) of right femur osteotomy to make distraction osteogenesis model. Electrophysiological changes of peripheral nerves were monitored by electromyography (EMG) pre-and postoperatively in all the femoral lengthening rats. The formation of callus was examined by X-ray every week after operation. The rats were sacrificed on 2nd, 4th, 6th weeks after the bone transport operation. Four-point bending test and histological staining examination were carried out to determine the osteogenesis in the distracted area. SPSS 21.0 was used for statistical analysis. Data of measurement were expressed as (Mean±SD). A non-parametric test was used to assess the statistical difference between groups. Graphs were plotted by GraphPad Prism 8.0 and considered statistically significant when P<0.05. Results:The results of Sciatic nerve function index (SFI), Compound muscle action potential (CMAP) and Motor nerve conduction velocity (MNCV) in group A were better than the group B and group C in both of before and after the surgery. At the 2nd and 4th weeks of the consolidation stage, X-ray showed that bone formation in group B was superior to groups A and C; HE and Safranin O staining showed that local capillary and cartilage formation in group B was significantly more than in groups A and C; Immunohistochemical staining showed that the expression levels of Osteopontin(Opn) and Osteocalcin(Ocn) in the distraction area of group B were higher than that of groups A and C. At the 6th week of the consolidation stage, the four-point bending test showed that the bone quality of group B was better than groups A and C. The differences of the results between groups shown above had statistical significance ( P<0.05). Conclusion:Bone regeneration in the distraction area of the bone lengthening group with sciatic nerve injury was better than that of the bone lengthening group without a never injury. This might be in relation to the fact that a distractive osteogenesis caused the secondary injury to the repaired nerve. The electrophysiological results showed that periodic changes took place in the repaired sciatic nerve caused by the stretch of femoral lengthening, and the injurious changes of sciatic nerve would be gradually relieved in 6th week after surgery.
ABSTRACT
Objective:To report the clinical effect of using polyfoliate anterolateral thigh perforator flap (ALTPF) in reconstruction of soft tissue defects of extremities.Methods:From April 2017 to January 2020, 21 cases of soft tissue defect in extremities were repaired by polyfoliate ALTPF, including 11 cases of traffic accident trauma, 8 of machine crush injury, and 2 of iatrogenic complications. There were 14 cases in calf and ankle, and 7 in hand and wrist. The area of defect was 17.0 cm×12.0 cm-20.0 cm×14.0 cm. Eight cases were complicated with fracture and bone exposure, 13 with tendon and nerve exposure. Thirteen cases had 2 adjacent wounds and 8 had large wound. The polyfoliate ALTPF was designed for wound repair. The patients entered follow-up regularly. The last follow-up included the colour, texture, shape, sensation of the flap and the scar of the donor area.Results:There was no infection in the recipient site of all 21 patients after operation, and all flaps survived. Two cases had venous crisis, with 1 was found in 5 hours after operation. Emergency exploration found that there were thrombosis in anastomosed veins. The flap survived completely after the thrombus removed and the embolized vein was anastomosed again. Another case was found with venous crisis at 1 lobe of flap in 2 hours after operation. Emergency exploration found that the anastomotic site between the superficial vein from the medial edge of the flap to the great saphenous vein and the superficial vein of the recipient area was embolised. The flap survived completely after the thrombus removed and the embolized veins was anastomosed again. The wounds of all donor sites healed in the first stage. All patients were followed-up for 6-30 (mean 12.3) months. All flaps had good colour and texture, with slightly bloated appearance and dull sensation. There was only a linear scar in the donor area, and the appearance evaluation was good.Conclusion:Polyfoliate ALTPF can be used to repair 2 large or adjacent wounds in 1 stage, reduce the damage of donor site. It is an ideal method to repair large or adjacent wounds of limb.