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BACKGROUND: Nano-hydroxyapatite/polyamide 66 composite (n-HA/PA66) has good biocompatibility, osteoinduction, osteoconductivity and osteogenesis. It is widely used in clinical fracture healing, spinal fusion, and other bone repair. OBJECTIVE: To observe the effect of n-HA/PA66 filling combined with locking plate in the treatment of fibrous dysplasia of femoral bone. METHODS: From May 2015 to May 2018, 15 patients with fibrous dysplasia of bone were admitted to Xingtai People’s Hospital Affiliated to Hebei Medical University. There were 4 males and 11 females, aged 16-58 years. The lesions were all located in the femur. They were all treated with n-HA/PA66 filling combined with locking plate. The patients were followed up for 18-40 months. Imaging examination (X-ray and CT scan) was carried out to evaluate the bone healing. Musculoskeletal Tumor Society (MSTS) score and Harris score were used to assess the functional recovery of patients after operation. RESULTS AND CONCLUSION: (1) X-ray films showed that there was a clear boundary between the transplanted bone and the host bone immediately after the operation. At 3 months after the operation, the transplanted bone was replaced partly by crawling. At 6 months, new bone formation was obvious. At 9-12 months, new bone formed completely. The transplanted bone was basically catabolized. At 18 months, the new bone was completely integrated with the host bone. The boundary between the new bone and the host bone disappeared. New bone and host bone are connected by direct trabecula. (2) At the last follow-up, CT images showed that the local lesions were eliminated; no recurrence or metastasis occurred; and the grafts healed completely. The G/N ratio was 0.78±0.09. (3) At the last follow-up, 15 patients’ pain all disappeared, MSTS score was 28.1±0.7. Harris score was 94.3. Daily physical activity was restored. (4) n-HA/PA66 composite material has obvious osteogenic effect on the bone defect caused by the removal of fibrous dysplasia. Locking plate fixation can make patients move early and obtain good postoperative function.
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Objective: To explore the effectiveness of nano-hydroxyapatite/polyamide-66 (n-HA/PA66) Cage in interbody fusion for degenerative lumbar scoliosis. Methods: A retrospective analysis was designed and conducted for 43 patients, who underwent posterior decompression and n-HA/PA66 Cage interbody fusion with correction of deformity between January 2013 and June 2016. Eighteen cases were single-level fusion (single-level group) and 25 cases were double-level fusion (double-level group). There was no significant difference in gender, age, body mass index, direction of convex, degree of apical rotation, fusion level, the number of osteoporotic patients, pre-operative intervertebral height of fusion segments, coronal Cobb angle, visual analogue score (VAS), and modified Oswestry Disability Index (ODI) between 2 groups ( P>0.05). The operation time, intraoperative blood loss, postoperative drainage, hospital stay, and complications of the operation were recorded. Modified ODI, VAS score, and MacNab criteria were adopted to assess clinical outcomes. Radiographic indexes, including intervertebral height of fusion segments, coronal Cobb angle, disc insertion depth, and the bone graft fusion rate, were also evaluated. Results: There was no significant difference in operation time, intraoperative blood loss, postoperative drainage, and hospital stay between 2 groups ( P>0.05). All patients were followed up 18-62 months (mean, 30.9 months). Wound complications, postoperative delirium, and Cage retropulsion occurred in 4 cases (2 cases in single-level group, 2 cases in double-level group), 1 case of single-level group, and 1 case of double-level group, respectively. The intervertebral height of fusion segments after operation significantly improved compared with preoperative ones in both groups ( P0.05). The disc insertion depth showed no significant difference between different time points after operation in 2 groups ( P>0.05) and between 2 groups at each time point after operation ( P>0.05). Bony fusion was obtained in all patients at last follow-up. The VAS score and modified ODI after operation in both groups were superior to those before operation ( P0.05). According to the MacNab criteria, the excellent and good rates at last follow-up were 94.4% and 84.0% in single-level group and double-level group, respectively. Conclusion: The n-HA/PA66 Cage can effectively restore and maintain the disc height of fusion segment, normal sequence, and biomechanical stability of the spine, and gain favorable effectivenss for degenerative lumbar scoliosis. And double-level fusion is superior to single-level fusion in maintaining disc height of fusion segment.
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Objective To investigate the therapeutic effects of nano-hydroxyapatite/polyamide 66/platelet-rich plasma com-pound(n-HA/PA66/PRP)on the recovery of rabbit femur bone defect.Methods 40 New Zealand rabbits were artificially made to be bone defect by resecting the 1 cm substantia ossea with periosteum of femur,and were divided into two groups averagely depen-ding on implanted materials:experimental group(n-HA/PA66/PRP),control group (n-HA/PA66).Every five rabbits were sacri-ficed on week 2,4,8,12,and the femur healing status was observed by X ray,histology,and immunohistochemistry.Results No rabbit was infected or died,no implantation objects dropped.Gross observation,X-ray result and histology results demonstrated that the experimental group began to have a new bone tissue at 2 weeks after the operation,with the extension of time,the experimental group new bone growth speed and the quantity was better than the control group.The Lane-Sandhu method X-ray score showed that the experimental group (6.80±2.05)points and the control group(4.20±1.30)points at 12 weeks after the operation,and there were significant differences between two groups(P 0.05).Conclusion PRP combined with n-HA/PA66 artificial bone could accel-erate the healing of bone defect,and the effect of repair of bone defect is better than that of n-HA/PA66 artificial bone in the early.
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Objective To detect the effect of a new bioactive bone screws composed of nanohydroxyapatite/polyamid 66/glass fiber (n-HA/PA66/GF) biomaterial on biological behavior of osteoblasts with a view to a later clinical application of the screws.Methods Mice osteoblasts were co-cultured with n-HA/PA66/GF biomaterial or its extract.Cell growth was detected under a microscope,cell proliferation using MTT assay,apoptosis by flow cytometry,osteocalcin by ELISA method,cell migration using Transwell invasion assay,cell adhesion and growth by scanning electron microscope,and cytoskeleton and actin filament distribution using immunofluorescene.Results Direct contact test demonstrated n-HA/PA66/GF material had no obvious cytotoxicity to osteoblasts.Extract of n-HA/PA66/GF material stimulated osteoblast proliferative activity over time with absorbance value of 0.96 ± 0.14,1.54 ± 0.15,and 2.39 ±0.27 respectively after 2,4,and 6 hours of coculture (P ＜ 0.05).The n-HA/PA66/GF material induced more osteoblasts to entering S period without obvious influence on apoptosis rate and promoted osteocalcin secretion.Migrated cells in medium supplied with n-HA/PA66/GF material or FBS was 8.73 ± 3.26 and 9.47 ± 3.29 in each visual field,but there was no significant difference (P ＞ 0.05).Osteoblasts had a regular form on the surface of n-HA/PA66/GF material,closely adhered to the surface,and reproduced and aggregated with each other to form stratified cell layers.However,nHA/PA66/GF material exhibited no obvious influence on distribution of cytoskeleton and actin filament.Conclusion The new n-HA/PA66/GF screws has excellent cytocompatibility with positive regulatory effect on cell growth,proliferation,secretion,adhesion,cycle,and osteocalcin secretion.
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BACKGROUND:There are various commonly used interbody fusion methods, such as autologous bone, al ograft bone and titanium-based posterior lumbar interbody fusion, and each method has its own advantages and disadvantages. OBJECTIVE:To observe the clinical efficacy of a bioactive nano-hydroxyapatite/polyamide 66 fusion cage in posterior lumbar interbody fusion for the treatment of lumbar disease. METHODS:A retrospective case analysis was conducted on 16 cases treated with posterior lumbar interbody fusion at the Department of Orthopedic, the First Affiliated Hospital of Gannan Medical University from July 2010 to December 2011, and al the patients were implanted with nano-hydroxyapatite/polyamide 66 biological activity fusion cage. RESULTS AND CONCLUSION:Al the patients were fol owed-up for 10-24 months, and the lumbar pain was significant improved, the lumbar visual analogue score, lumbar Japanese Orthopaedic Association score and Oswestry disability index score were significantly improved during the final fol ow-up period (Pfusion without nano-hydroxyapatite/polyamide 66 fusion cage displacement or subsidence. The results indicate that nano-hydroxyapatite/polyamide 66 fusion cage for the treatment of posterior lumbar interbody fusion can reconstruct the lumbar stability and provide immediate stability after implantation, and has good biological activity.
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Objective To study the clinical effects of the artificial vertebral body of the biomimetic nano-hydroxyapatite/polyamide 66 (n-HA/PA66) composite for the structural reconstruction and the height restoring of the vertebral body in the thoracolumbar fractures by the anterior surgical procedures. Methods From December 2003 to January 2006, 42 patients with thoracolumbar fractures received the anterior surgical procedures to decompress and reconstruct the spinal vertebral structure with the artificial vertebral body of the n-HA/PA66 composite. Among the patients, there were 28 males and 14 females, aged 17-67 years, averaged 43.6 years. The thoracolumbar fractures developed at T12 in 5 patients, at L1 in 17, at L2 in 14, and at L3 in 6. The height of the anterior border of the vertebral body amounted to 29%-47% of the vertebral body height, averaged 40.6%. The Cobb angle on the sagittal plane was 21-38° averaged 27.6°. According to the Frankel grading scale, the injuries to the nerves were as the following: Grade A in 7 patients, Grade B in 19, Grade C in 8, Grade D in 6, and Grade E in 2. Results All the 42 patients were followed up for 6-25 months. Among the patients, 36 were reconstructed almost based on the normal anatomic structure, and 6 were well reconstructed. The mean height of the anterior border of the vertebral body was 40.6% of the vertebral body height before operation but 91.7% after operation. And the reconstructed height of the vertebra was maintained. The mean Cobb angle on the sagittal plane was 27.6°before operation but 13.4° after operation. All the patients had a recovery of the neurological function that had a 1-grade or 2-grade improvement except 7 patients who were still in Grade A and 2 patients who were in Grade D. The implant was fused 3-5 months after operation. No infection, nail break, bar/plate break or loosening of the internal fixation occurred. Conclusion The artificial vertebral body of the biomimetic n-HA/PA66composite can effectively restore the height and the structure of the vertebra, can be fused with the vertebral body to reconstruct the spinal structural stability effectively, and can be extensively used in the clinical practice.
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0. 05),while that in group C was significantly lower(P
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[Objective]To investigate the in vitro antibacterial effect and biocompatibility of the bone filling materials of TiO_2-Ag-nHA/PA66.[Method]The inhibition ring test and plate-counting method were used to evaluate anti-bacterial performance against staphylococcus aureus ATCC25923 and escherichia coli ATCC25922.The effects of antiadhesion of staphylococcus aureus and escherichia coli were observed by scanning electron microscope(SEM).The cytotoxicity was detected via MTT and the biocompatibility of biofilm was evaluated by acute haemolysis test.[Result]The inhibition zone diameter of staphylococcus aureus and escherichia coli reaches the maximum at the first day[(23.6?1.14) mm and(18.8?0.84 mm)].The diameter of inhibition zone was lessening with the time going.It could effectively inhibite the survival and growth of staphylococcus aureus and escherichia coli within 33 and 24 days.The bacteria killing rate was 94.18% and 85.96%.Scanning electron microscope showed that the adhered bacteria in the experimental group were obviously fewer than in the control group.The MTT graded the cytotoxicity of the bone filling materials of TiO_2-Ag-nHA/PA66 as 1.The acute haemolysis assay showed that the hemolytic rate of bone filling materials of TiO_2-Ag-nHA/PA66 was 0.28%.[Conclusion]The bone filling materials of TiO_2-Ag-nHA/PA66 has good biocompatibility,significant antibacterial property against staphylococcus aureus and escherichia coli.No obvious cytotoxicity or erythrocyte destruction was found.
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Objective:Tostudy the MRI with X-ray in the ability of bony generation by the way of the experiment of repairing bone defects with n-HA/PA66. Methods:30 New Zealand rabbits were avalued whose condyle of tibia in one side was performed boring which was 3mm diameter and 5mm depth with n-HA/PA66 composite implanting. The specimens were taken respectively in different times:2nd 4th 6th 8th 12th week after surgery,and were examined by the methods of plain roentgenography、histology and magnetic resonance imaging. Results:(1)MRI and X-ray:From the 4th week,n-HA/PA66 composite had the poor defined border and the signal inter-material had become more variform,more obvious enhancement,at the same time in the X-ray,there were more and more bony generation(.2)The histology showed that a layer of interface membrane forming. From the 4th week,The interface membrane had been widest and the number of cells was increasing. Till the 12th week,there were some bone trabecula formed and the HA were separated into small islands,more osteoclasts appeared. Conclusion:The experimental results showthat the perfect radiology technique is useful to predict the bone transplantation. Furthermore it is easy to operate in clinical setting,and the n-HA/PA66 Composite has the attribute of good biocompatility and osteoconductibity,which can be manifested by plain roentgenography and magnetic resonance imaging.
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Objective: To discuss the radiological evaluation after the experiment implanted artificial vertebral lamina made from n-HA/PA66 into the defect of vertebral lamina,in order to evaluate its value in preventing the complication of postlaminectomy.Methods:22 male dogs aged one year were classified randomly into three groups: the experimental group(13 dogs)and the control group(9 dogs).The specimens were examined by the methods of plain roentgenography,MRI and histology.Results:The X-ray: in the experimental group,it was becoming cloudy around the operative area in the 8th week;till 24th week,the density of the operative area was the same with the density of bone.The histology: in the experimental group,from the 8th week,there were many cartilage cells and lamellar bone observed.While in the control group,it was just fibrous layer forming.MRI:the reconstructed segment after the laminoplasty was detected clearly by MRI,which coincided with the histology.Compared with the control segment,the numbers of the area of vertebral canal and the sagital axis were significantly different(P