There are many reasons for bone defects.Trauma,malignant tumor resection,chronic osteomyelitis and congenital factors can all lead to bone defects.The treatment methods include autogenous cancellous bone grafting,vascularized fibular grafting,distraction osteogenesis and Masquelet techniques,etc.Masquelet technique was first discovered by Masquelet et al.in 1986.It provides a simple and safe method for the treatment of large bone defects.This technique has two stages,and the first stage includes wound thoroughly debridement,maintenance of the stability of fracture,placement of (antibiotic) cement spacer,and closure of the wound without tension,then 6 to 8 weeks later,the second stage will be conducted including performing a longitudinal incision of the induced membrane,removal of the bone cement and bone graft.Bone cement includes polymethyl methacrylate (PMMA),calcium phosphate,calcium sulfate and other materials,if necessary,antibiotics could be combined at the same time.Different bone cement induced biofilmhas different characteristics.Induced membrane can secrete transforming growth factor (TGF-β1),bone morphogenetic protein 2 (BMP-2),platelet endothelial cell adhesion molecule-1 (PECAM-1),and vascular endothelial growth factor (VEGF) and other osteogenesis growth and angiogenesis related factors,then an independent space is built to isolate the bone graft from outside environment,avoiding the phenomenon of bone graft absorption and providing a stable biological environment of bone defect.Masquelet technique is simple to operate,safe,accompanied by fewer complications,less demanding to the recipient area,easy to be accepted by patients and promoted clinically.It is applicable to bone defects in all parts and has great potential for clinical application and especially suitable for large segmental bone defectwhich is ineffective in other treatment methods.

Objective: To investigate the clinical efficacy of minimally invasive plate oseoynthesis (MIPO) assisted by a self-designed lower limb axial tractor in the treatment of complex tibial plateau fractures. Methods: The data were retrospectively analyzed of the 31 patients who had undergone surgical treatment for complex tibial plateau fractures from June 2015 to April 2018 at Department of Orthopeadics, Hospital Affiliated to Binzhou Medical College. MIPO was conducted with the assistance of the axial tractor in 17 of them. They were 12 men and 5 women with an age of 50.8±14.7 years, with 8 cases of Schatzker type Ⅴ and 9 ones of Schatzker type Ⅵ. MIPO was conducted without the assistance of the axial tractor but with the assistance of manipulation reduction in the other 14 patients. They were 9 men and 5 women with an age of 48.9±9.5 years, with 6 cases of Schatzker type Ⅴ and 8 ones of Schatzker type Ⅵ. The 2 groups were compared in terms of operation time, intraoperative bleeding, and Rasmussen scores for knee function and medial angle of the proximal tibia at the last follow-up. Results: The 2 groups were comparable due to insignificant differences in the preoperative general data between them (P>0.05). The tractor and manipulation groups were followed up for a mean of 9.8 months and 10.9 months respectively. Bone healing was achieved in all patients. For the tractor and manipulation groups, respectively, the operation time was127.8±40.8 min and 174.1±66.8 min, and the intraoperative bleeding 115.6±41.7 mL and 184.3±91.4 mL, showing significant differences between them (P<0.05). In the tractor group at the last follow-up, the knee flexion was 126.1°±9.3°, the medial angle of the proximal tibial 87.8°±1.4°, the posterior inclination angle 8.7°±3.8° and the Rasmussen score 26.5±2.9 points; in the manipulation group at the final follow-up, the knee flexion was 124.7°±8.9°, the medial angle of the proximal tibial 86.9°±2.1°, the posterior inclination angle 9.8°±4.1° and the Rasmussen score 25.6±3.2 points. There were no significant differences between the 2 groups in the above items (P>0.05). Loss of force line was observed in none of the patients at the last follow-up. Conclusion Compared with conventional manipulation reduction, use of our self-designed lower limb axial tractor can shorten operation time, reduce bleeding and facilitate reduction of fracture fragments in the treatment of tibial plateau fractures of Schatzker types Ⅴ and Ⅵ.

Objective To investigate the effect of periosteum deficiency on the treatment of segmental bone defect of lower extremity by Ilizarov bone transport Technique.Methods From April 2009 to April 2016,data of 54 cases with lower limb segmental bone defect who were treated by Ilizarov bone transport technique were retrospectively analyzed.According to intraoperative observation of the distribution of periosteum at the osteotomy site,all cases were divided into two groups.There were 10 cases in absent periosteum group,including 6 males and 4 females,aged from 23 to 57 years old (mean,38.20±9.90 years old).There were 3 cases locating at femur,and 7 cases at tibia.4 cases had non-infective bone defect,while the other 6 had infective bone defect.Segmental bone defect ranged from 4.0 to 14.0 cm (mean,6.85±2.87 cm).There were 44 cases in normal periosteum group,including 32 males and 12 females,aged from 22 to 65 years old (mean,38.90±10.10 years old).There were 9 cases locating at femur and 35 cases at tibia.12 cases had non-infective bone defect,while 32 cases had infective bone defect.Segmental bone defect ranged from 4.0 to 9.0 cm (mean,6.09±1.54 cm).Visual analogue scale (VAS) was used to estimate the pain during bone transport.The distraction index,bone healing index,external fixator index was collected to evaluate the distraction osteogenesis and mineralization.The Paley method was utilized to appraisal the function of proximal joints in bone transport.Results All the 54 cases were followed up for 24-48 months,with an average of 28.50±5.70 months.All skin and soft tissue defects were satisfied healed.All limbs were restored to their original lengths,and bone healing was eventually achieved.There were no statistically significant differences in the distraction index,bone healing index,external fixator index,VAS between absent periosteum group (12.29± 1.04 d/cm,39.00±3.96 d/cm,51.25±3.69 d/cm,3.30± 1.77 score) and normal periosteum group (11.67±0.96 d/cm,38.07±4.22 d/cm,49.74±4.25 d/cm,3.36± 1.66 score)(P ＞ 0.05).Paley adjacent joint function evaluation showed no statistically difference between absent periosteum group [good rate 100％(10/10)] and normal periosteum group [good rate 97.7％ (43/44)] (P=0.901).The overall incidence of complications was 20.0％ (2/10) in the absence of periosteum group,with 1 case of mild infection and 1 cases of tissue contracture incarcerated at the docking site.The overall incidence of complications was 27.3％ (12/44) in the normal of periosteum group,with 2 cases of mild infection,3 cases of poor limb strength alignment,6 cases of tissue contracture incarcerated at the docking site and 1 case of severe foot drop deformity.There was no statistically significant difference in the overall incidence of complications between the two groups (P=0.636).Conclusion The absence of periosteum at the epiphyseal osteotomy site hasno significant effect on Ilizarov bone transport technique in the treatment of segmental bone defects of lower limbs in bone regeneration and healing,mineralization and bone remodeling,and does not increase the incidence of complications.