Objective To observe the effect of vascular endothelial growth factor (VEGF) in fracture healing and to investigate the influence of VEGF and VEGF antibody in fracture healing. Methods One hundred and five rabbits were used tomake fracture model in the left radius and randomly divided into control group,VEGF group and VEGF antibody group. VEGF and VEGF antibody were used in the VEGF group and VEGF antibody group respectively, then the blood flow of the fracture ends was measured by single photon emission computed tomography (SPECT) 8,24 , 72 hours, 1, 3, 5 and 8 weeks after fracture, the X-ray films of the fracture sites were taken after 1, 3, 5 and 8 weeks to observe the fracture healing. Results The blood flow of the fracture ends in the VEGF groupincreased during aperiod from 8h to 3wk after fraction when compared with that of the control group, and no obvious difference was seen on the X-ray films between the two groups. In the VEGF antibody group, the blood flow of the fracture ends decreased obviously when compared with that of the control group. The fracture healing processwas interfered seriously and nonunion change was seen in the fracture site. Conclusion The lack of VEGF will interfere with the fracture healing process and result in nonunion in the fracture site. Administration of ectogenous VEGF may promote fracture healing by increasing the blood flow of the fracture ends.
In order to study the biomechanical effect of cyclic loads on revascularization in bone healing, 20 rabbits were chosen for following experiments. Two 2 mm in diameter holes were made at the middle segment of both right and left tibia. A 2 mm in diameter nail was put in 15 mm proximal to the upper hole, and another was put in 15 mm distal to the lower hole. The wound was covered by direct suture with the ends of the nails kept 15 mm out of skin. The medial ends of the two nails were fixed by an iron plate, while the lateral ends were left for cyclic loads. Three Hz cyclic loads, which was near to the cyclic forces when a rabbit runs, was added to the left tibia for experiment, and no loads was add to the right tibia for control. A group of five rabbits were sacrificed respectively in 5, 10, 20 and 30 days postoperatively. The solution of 2% India ink and gelatin was irrigated from aorta to the bone defects. Then the tibia was removed for histologic study. The changes of cells and microvessel were observed. It was shown that the revascularization in experiment group was about 7 days earlier than that of control. The effect was at its peak from 10 to 30 days. It was concluded that cyclic loads could promote revascularization in the healing process of bone defect.
ObjectiveTo summarize the application status and progress of platelet-rich plasma (PRP) in clinical orthopedics. MethodsThe recent related literature concerning the application of PRP in clinical orthopedics was extensively reviewed and analyzed. ResultsRecently, a large number of clinical studies on PRP have been carried out, which are applied in bone defects or nonunion, spinal fusion, osteoarthritis and cartilage injuries, ligament reconstruction, muscle strain, tendon terminal diseases, and a variety of acute and chronic soft tissue injuries. Some results show certain effectiveness, while others demonstrate invalid. ConclusionEasily drawing, achieving autologous transplantation, and the biological repair potential of the musculoskeletal tissues make PRP to be widely used in clinical orthopedics. However, there are still no uniform standards accepted and reliable clinical guidelines about the application of PRP. Furthermore, a variety of PRP products and their respective indications are also different. The clinical evidences with the greater sample size and higher quality are still needed to further support the safety and effectiveness of PRP in clinical orthopedics.
Objective To compare the healing process and clinical results of bioactive glass and allogenic bone in the repair of bone defects after benign bone tumor curettage. Methods Between November 2011 and December 2012, 20 patients with benign bone tumor received bioactive glass and allogenic bone for repair of bone defects after benign bone tumor curettage. There were 17 males and 3 females, aged 9-68 years (median, 18.5 years). The mean course of disease was 3.3 months (range, 1-9 months). Pathological examination revealed that there were 7 cases of chondroblastoma, 5 cases of bone cyst, 2 cases of non-ossifying fibroma, 2 cases of enchondroma, 1 case of vascular tumor of bone, 1 case of lipoma of bone, 1 case of osteoid osteoma, and 1 case of chondromyxoid fibroma. The lesion located at the femur in 5 cases, at the tibia in 11 cases, at the humerus in 1 case, at the calcaneus in 2 cases, and at the talus in 1 case. The bioactive glass and allogenic cancellous bone were implanted in the cavity at the same time. The Musculoskeletal Tumor Society (MSTS) function evaluation score was used for evaluation of postoperative limb function. According to the imaging and clinical benefit, the healing processes of two kinds of implants were evaluated. The healing rate and healing time were compared. The distribution of the bioactive glass was divided into two layers: the layer close to host bone and the layer close to allogenic bone. The bone ingrowth time and bone resorption time in different layers were evaluated and compared. Results All cases were followed up 12-42 months (mean, 34.5 months). All incisions healed by first intention. There were no complications of wound infection or deep infection, rejection, nonunion of bone, fracture at bone graft site, and collapsing of articular surface. There was no tumor recurrence during follow-up. The mean MSTS functional score was 29.5 (range, 28-30) at last follow-up. Complete healing was observed in 11 cases and healing in 9 cases. The healing rates of two kinds of implants were both 100%. The healing time of bioactive glass and allogenic bone was (4.7±1.3) months and (5.2±1.6) months, respectively, showing no significant difference (t=-1.240, P=0.244). The bone ingrowth time and the bone absorption time were (3.6±0.9) months and (3.7±1.0) months in the layer close to host bone and were (4.2±1.3) months and (4.2±1.3) months in the layer close to allogenic bone, all showing no significant difference (t=1.785, P=0.097; t=1.476, P=0.172). Conclusion For the repair of bone defects after benign bone tumor curettage, bioactive glass can achieve satisfactory healing result and has good safety.