Abstract In order to repair the bone defect afteroperation of benign lesion of extremity, the fetal demineralized bone was applied in 10 cases. These cases were followed up for 6 months to 8 years. The results showed that the grafted bone was integrated with the host bone in 6 months. Noadverse effect was found. The demineralized bone did not induce rejection. The advantages of using fetal demineralized bone were as follows: easily obtainable,its preparation and method of storage simple, and low finacial cast.
Objective To explore the biomechanical difference between the different fixations of cortical bone plate allograft. Methods Twenty-seven cadaveric femurs were harvested and were made into the simulated fracture models, which were equally divided into Groups A, B and C. In Group A, the models were fixed with 2 bone plate allografts (110 mm×10 mm×3 mm); in Group B, the models were fixed with 2 struts (110 mm×10 mm×3 mm) and 5 bone screws; in Group C, the models were fixed with 1 strut (110 mm×10 mm×3 mm) and 5 bone screws. The biomechanical tests for the three-piont bending, torsion, and compression were performed. The parameters studied included the values of the displacements in the three-piont bending tests and the compression tests, and the maximum loads during the bending, the compression, and the torsion. Results As for all the stiffness parameters tested, Group A showed the greatest displacements among the threegroups（P＜0.05）, except the compressive stiffness parameter, which was similar to that in Group B. The maximum loads of the three-point bending, the torsion, and the compression in Group A were 1.65±0.34 kN, 554.3±49.34 N, and 7.78±0.82 Nm, respectively; in Group B, they were 1.12±0.37 kN, 428.00±37.40 N,and 3.39±0.22 Nm, respectively; in Group C, they were 0.71±0.46 kN, 218.67±36.53N, and 1.74±0.12 Nm, respectively. Group A had a significantly greater strengththan the other 2 groups(P＜0.05). Conclusion The strength of the cortical bone plate allograft is related to its different fixations. The two cortical bone plate allografts have a greater strength and stiffness than the struts fixed with the bone screws, which can meet the clinical requirement.
ObjectiveTo explore whether FTY-720P could enhance the effect of allograft bone for bone defect repair by suppressing osteoclast formation and function. MethodAnimal experiment:Forty-eight New Zealand white rabbits were selected to establish the tibia defect model (1.5 cm in length) and were divided into 4 groups (n=12) . Defect was not repaired in group A, defect was repaired with allograft bone in group B, with autogenous fibula in group C, and with allograft bone and FTY-720P in group D. Lane-Sandhu scoring system and bone density examination were used to evaluate the effect at 2, 4, 8, and 12 weeks after operation. Cell experiment:Bone marrow-derived mononuclear phagocytes (BMMs) were harvested from 1-month-old Sprague Dawley rats and induced into osteoclasts with macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL), then were identified with tartrate-resistant acid phosphatas (TRAP). According to different concentrations of FTY-720P before induction, experiment was divided into 0, 500, 600, 700, 800, 900, 1 000, and 1 500 ng/mL groups. The effect of FTY-720P was studied by counting the number of osteoclasts and the number of bone resorption lacunae made by osteoclasts. ResultsAnimal experiment:Lane-Sandhu score showed no significant difference between groups at 2 weeks after operation (P>0.05) , but the score was significantly better in groups C and D than groups A and B, and in group B than group A (P<0.05) . The bone density of group C was significantly greater than that of groups A, B, and D at 2 weeks after operation (P<0.05) , but no significant difference was found among groups A, B, and D (P>0.05) ; the bone density of groups B, C, and D was significantly greater than that of group A at 4, 8, and 12 weeks (P<0.05) , but no significant difference was shown among groups B, C, and D (P>0.05) . Cell experiment:BMMs could be induced into osteoclasts by the addition of M-CSF and RANKL, which could be proved by counting the number of the nuclear and TRAP staining. The osteoclasts were significantly more in 0, 500, 600, 700, 800, 900 ng/mL groups than 1 000 and 1 500 ng/mL groups (P<0.05) , in 0, 500, 600, and 700 ng/mL groups than 800 and 900 ng/mL groups (P<0.05) , in 0, 500, 600 ng/mL groups than 700 ng/mL group (P<0.05) ; and there was no significant difference between the other groups (P>0.05) . The number of bone resorption lacunae in 0, 500, 600, and 700 ng/mL groups was significantly higher than that in 800, 900, 1 000, and 1 500 ng/mL groups (P<0.05) , and it was significantly higher in 0, 500 and 600 ng/mL groups than 700 ng/mL group (P<0.05) , but difference was not significant between the other groups (P>0.05) . ConclusionsFTY-720P combined with allograft bone for bone defect repair can have the same effect to autogenous bone by means of inhibiting osteoclast formation and function, which reduces bone loss.
ObjectiveTo explore the feasibility of chitosan/allogeneic bone powder composite porous scaffold as scaffold material of bone tissue engineering in repairing bone defect. MethodsThe composite porous scaffolds were prepared with chitosan and decalcified allogeneic bone powder at a ratio of 1∶5 by vacuum freeze-drying technique. Chitosan scaffold served as control. Ethanol alternative method was used to measure its porosity, and scanning electron microscopy (SEM) to measure pore size. The hole of 3.5 mm in diameter was made on the bilateral femoral condyles of 40 adult Sprague Dawley rats. The composite porous scaffolds and chitosan scaffolds were implanted into the hole of the left femoral condyle (experimental group) and the hole of the right femoral condyle (control group), respectively. At 2, 4, 8, and 12 weeks after implantation, the tissues were harvested for gross observation, histological observation, and immunohistochemical staining. ResultsThe composite porous scaffold prepared by vacuum freeze-drying technique had yellowish color, and brittle and easily broken texture; pore size was mostly 200-300μm; and the porosity was 76.8%±1.1%, showing no significant difference when compared with the porosity of pure chitosan scaffold (78.4%±1.4%) (t=-2.10, P=0.09). The gross observation and histological observation showed that the defect area was filled with new bone with time, and new bone of the experimental group was significantly more than that of the control group. At 4, 8, and 12 weeks after implantation, the bone forming area of the experimental group was significantly larger than that of the control group (P < 0.05). The immunohistochemical staining results showed that osteoprotegerin (OPG) positive expression was found in the experimental group at different time points, and the positive expression level was significantly higher than that in the control group (P < 0.05). ConclusionChitosan/allogeneic bone powder composite porous scaffold has suitable porosity and good osteogenic activity, so it is a good material for repairing bone defect, and its bone forming volume and bone formation rate are better than those of pure chitosan scaffold.
ObjectiveTo investigate the effectiveness and technical key points of limb salvage surgery by allotransplantation of cryopreservated vascularized bone in children and adolescents with osteosarcoma. MethodsA retrospective analysis was made on the clinical data of 21 children and adolescents with osteosarcoma receiving limb salvage surgery by allotransplantation of cryopreservated vascularized bone from their relatives between February 2004 and April 2012. There were 13 males and 8 females, aged from 7 to 16 years (mean, 12.6 years). According to Enneking stage system, 15 cases were rated as stage ⅡA and 6 cases as stage ⅡB. The tumors located at the distal femur in 10 cases, at the proximal femur in 1 case, at the proximal tibia in 8 cases, at the proximal humerus in 1 case, and at the distal radius in 1 case. Imaging examination showed that epiphyseal extension of malignant bone tumors in 7 cases. The iliac bone allograft with deep iliac vessels was obtained from their lineal consanguinity. After preservation by a twostep freezing schedule, the iliac bone allograft with deep iliac vessels was implanted into the bone defect area after tumor resection. The size of iliac bone flap was 8.0 cm×3.0 cm×2.0 cm-14.0 cm×5.0 cm×2.5 cm. Reserved joint surgery was performed on 16 cases and joint fusion surgery on 5 cases, and external fixation was used in all cases. The chemotherapy was given according to sequential high-dose methotraxate, adriamycin, and cisplatine before and after operation. ResultsAll 21 cases were followed up from 5 months to 11 years (mean, 6.4 years). At 2 weeks after operation, the erythrocyte rosette forming cells accounted for 56.7%±3.9%, showing no significant difference when compared with that of normal control (58.3%±4.3%) (t=1.56, P=0.13), which suggested no acute rejection. At 4 weeks after operation, single photon emission computerized tomography bone scan indicated that the blood supply of bone graft was rich, and the metabolism was active. At 12 weeks after operation, the digital subtraction angiography showed the artery of iliac bone flap kept patency. X-ray films showed that malunion and non-union occurred at 5 and 6 months after operation in 1 case, respectively. The bone graft healed in the other patients, and the healing time was 3.2-6.0 months (mean, 4.4 months). At last follow-up, American Musculoskeletal Tumor Society (MSTS) score was significantly improved to 26.80±2.14 from preoperative value (17.15±1.86) (t=-4.15, P=0.00). The survival rate was 85.7% (18/21) and the recurrence rate was 9.5% (2/21). ConclusionAllotransplantation of cryopreservated vascularized bone from the relatives provides a new method for the treatment of osteosarcoma in children and adolescents. A combination of allotransplantation and chemotherapy can achieve the ideal treatment effect. The correct cutting, preservation, and transplantation of the donor bone, and indication are the key to improve the effectiveness.
Objective To investigate the long-term effectiveness of uncemented allograft-prosthesis composite (APC) for reconstruction of bone defects after proximal femur tumor resection. Methods Between June 2007 and March 2014, 21 patients who underwent uncemented APC reconstruction of proximal femur after tumor resection were retrospectively evaluated. There were 9 males and 12 females with an average age of 33.2 years (range, 19-54 years). There were 9 cases of giant cell tumor of bone, 5 cases of osteosarcoma, 4 cases of osteoblastic osteosarcoma, 2 cases of chondrosarcoma, and 1 case of undifferentiated pleomorphic sarcoma. Thirteen cases of benign bone tumors were all classified as stage 3 by Enneking staging; and 8 cases of malignant bone tumors were classified as grade ⅡB in 7 cases and grade ⅡA in 1 case according to the American Joint Committee on Cancer (AJCC) staging system. Among them, 7 patients underwent reoperation after recurrence, and the rest were primary operations; 8 patients presented with pathological fractures. The preoperative Harris hip score (HHS) and American Musculoskeletal Tumor Society (MSTS) score was 40 (30, 49) and 9.1±3.5, respectively. The length of osteotomy was 80-154 mm, with an average of 110 mm. At 1 year after operation and last follow-up, HHS and MSTS scores were utilized to evaluate the function of hip joint; the gluteus medius strength score was used to evaluation of the hip abduction function. Image examinations were taken at 1, 3, 6, 9, and 12 months after operation and every year thereafter to assess the union of allograft-host bone interfaces. Intra- and post-operative complications were also recorded. Results All patients were followed up 84-163 months (mean, 123.5 months). At 1 year after operation and last follow-up, the HHS and MSTS scores significantly improved when compared with the preoperative scores (P<0.05). However, there was no significant difference in the HHS score, MSTS score, and gluteus medius strength score between the two time points after operation (P>0.05). Image examination showed that all allograft-host bone interfaces achieved union after 5-10 months (mean, 7.6 months). At last follow-up, all patients had bone resorption, including 11 severe cases, 4 moderate cases, and 6 mild cases; the bone resorption sites included Gruen 1, 2, and 7 regions. Complications included 10 fractures and 1 prosthetic fracture. Local recurrence occurred in 3 patients and pulmonary metastasis in 3 patients. Conclusion Uncemented APC is a reliable method for the reconstruction of bone defects after proximal femur tumor resection. It has the good long-term effectiveness and possesses obvious advantages in the union at the bone-bone surface.
OBJECTIVE: To observe the difference of the fracture reparation using autogeneic-iliac bone and allogenic bone. METHODS: Comminuted fracture of humerus in two sides were made in rabbits. Autogeneic-iliac bone was implanted in one side, while allogenic bone of equal capacity was implanted in the other side. General observation, X-ray, and HE histologic section were done when the rabbits were put to death in different stages. RESULTS: One week after implantation, the graft had been enclosed by connective tissue without infiltration of the inflammatory cells. At the 2nd week, the graft had been enclosed in osteoplastic granulation tissue, and the cartilage callus had formed. At the 3rd week, there had been broken sequestrum among the callus; the cartilage had actively formed the bone; and the medulla had been making. At the 4th week, the sequestrum had disappeared, and the mature callus had appeared; the osteoblasts had arranged in a line around the edge of the mature callus. At the 5th week, the callus was b, compact and approached mature bones. At the 6th week, there had been the compact lamellar structures and the complete haversian’s systems. There was no significant difference between callus of two sides by using image quantitative analysis in the 3rd, 4th week (P gt; 0.05). CONCLUSION: The allogenic bone has good histocompatibility and bone conduction effect, and can be used for bone transplantation substitute with autogenous-iliac bone.
ObjectiveTo explore the fusion effect of allograft Cages on transforaminal lumbar interbody fusion (TLIF).MethodsThe clinical data of 30 patients (38 vertebral segments) who underwent TLIF with allograft interbody fusion Cages between January 2015 and January 2017 were retrospectively analysed. There were 25 males and 5 females with an average age of 56.9 years (range, 44-72 years). The lesions included 20 cases of lumbar disc herniation, 7 cases of lumbar spondylolisthesis, and 3 cases of lumbar spinal stenosis. The operation section included 4 cases of L3, 4, 13 cases of L4, 5, 5 cases of L5, S1, 6 cases of L4, 5-L5, S1, and 2 cases of L3, 4-L4, 5. The disease duration was 6-36 months (mean, 12 months). The clinical effectiveness was evaluated by visual analogue scale (VAS) score, Oswestry disability index (ODI), and Japanese Orthopaedic Association (JOA) score at preoperation, 3 months and 6 months after operation, and last follow-up. The fusion rate was evaluated by anteroposterior and lateral X-ray films and CT three-dimensional reconstruction at 3 and 6 months after operation. The intervertebral space height was measured on anteroposterior and lateral X-ray films at preoperation, 3 days, 3 months, and 6 months after operation.ResultsThe operation time was 2.1-4.3 hours (mean, 3.1 hours), and the intraoperative blood loss was 150-820 mL (mean, 407.5 mL). The follow-up time was 8-25 months (mean, 16.4 months). One Cage split at 6 months after operation without Cage movement and neurologic symptoms; none of the other patients had Cage prolapse, displacement, and fragmentation. No local or systemic allergy or infection signs was found in all patients. No nerve compression or symptoms was observed during the follow-up. The postoperative VAS score, ODI score, and JOA score improved significantly when compared with preoperative scores (P<0.05); and the scores at 6 months and at last follow-up were significantly improved when compared with those at 3 months after operation (P<0.05); but no significant difference was found between at 6 months and at last follow-up (P>0.05). The fusion rate was 55.3% (21/38), 92.1% (35/38), and 100% (38/38) at 3 months, 6 months, and last follow-up postoperatively. The intervertebral space height was increased significantly at 3 days, 3 months, 6 months, and last follow-up postoperatively when compared with preoperative ones (P<0.05); and the loss of intervertebral space height was significant at last follow-up when compared with postoperative at 3 days (P<0.05).ConclusionThe allograft interbody fusion Cage contributes to the spine interbody fusion by providing an earlier stability and higher fusion rate.
Abstract In order to study the possibility of repairing bone defect by cryopreserved vascularized bone allograft, 8 dogs were divided into 2 groups. In the experimental group, 15% dimethylsulfoxide (DMSO) was used as a cryoprotective agent, the posterior segments of dog s rib, pedicled with intercostal vesseles, were cryopreserved by a two-step freezing procedure,stored in liquid nitrogen for 96 hours, and then transplanted as allografts to theiliac bone defects of recipients by vascular anastomosis. In the control group, the autografts were transplanted in the same procedure. Immunosuppersive agents were administrated postoperatively for 3 weeks. The specimens were analyzed by immune response monitoring (IL-2, T cell subsets), SPECT scanning, angiography and pathologic examination. The results showed that the allografts had good blood supply and active osteocyte metabolism, bone healing of the allografts was perfect at 3 months and no evidence of immunologic rejection. The process of bone healing of allografts should be further investigated.
Objective To investigate the efficacy of the pedicle screw fixation and allograft bone in posterior spinal fusion for the treatment of thoracolumbar vertebral fractures. Methods From September 2006 to March 2008, 105 cases of thoracolumbar vertebral fractures were treated with allograft bone in posterior spinal fusion after the pedicle screw fixation,including 75 males and 30 males aged 15-65 years (mean 37 years). The mixture which consisted of spinous process and vertebral plate sclerotin and homogeneity variant bone was used as bone graft to implant into articular process and processus transversus space or vertebral plate space. The time from injury to surgery varied from 8 hours to 21 days, with an average of 3 days. There were 52 cases of fall ing injuries from height, 35 cases of traffic accident injuries, 11 cases of bruise injuries and 7 cases of tumbl ing injuries. Before operation, the primary cl inical symptoms of patients included local pain combined with l imitation of activity, 30 cases compl icated by various degrees of spinal cord and nerve root functional disturbance. According to Mcaffee classification, there were 7 cases of flexion depressed fractures, 86 cases of blow-out fractures, 9 cases of Chance fractures and 3 cases of dislocation-fracture. According to Frankel grade, there were 11 cases of grade A, 2 cases of grade B, 7 cases of grade C, 10 cases of grade D and 75 cases of grade E. The X-ray examination of all patients denoted that the bodies of injuryed vertebra were compressed and wedge-shaped, and the CT scan showed that 98 cases had spinal stenosis. After 2 weeeks and 3, 6, 12 months, the X-ray films were taken to evaluate bone graft fusion. The Cobb angle was measured. The recovery of nerve function was analyzed. Results The operation time was 55-180 minutes (mean 90 minutes) and the blood loss was 100-900 mL (mean 200 mL). All patients achieved heal ing by first intention with no compl ication. After operation, 93 cases were followed up for 6-15 months with an average of 11 months. Except for 11 patients who were at grade A before operation, one to two grade recover was observed in other patients. The average Cobb angle of injury segment was improved from preoperative 32.1° to postoperative 5.2°. The height of anterior border of injuried vertebral body was recovered from the preoperative average compressed remaining height 61.5% to postoperative 96.8%. The vestigial degree of canal is spinal is anteroposterior diameter was recovered from preoperative 65.7% to postoperative 89.9%. Imageology examination showed that all the patient achieved bone union within 6 months. The fusion rate of bone graft in spinal fusion was 100%. No loosening and breaking of nails occurred. Conclusion Pedicle fixators can restore and fix the thoracolumbar fractures, and the combination of autograft and allograft bone transplantation is a safe, rel iable and effective method.