ObjectiveTo evaluate the effect of poly-amino acid/nano-hydroxyapatite/calcium sulfate (PHC) Cage in lumbar interbody fusion of the goat. MethodsEighteen mature female goats (weighing 29-33 kg) were divided into 3 groups randomly: PHC Cage group (group A), titanium Cage group (group B), and ilium group (group C). A left extraperitoneal approach was used to establish the animal model of discectomy and interbody fusion with Cage or ilium. The general situation was observed for 24 weeks after operation. X-ray films were taken to measure disc space height (DSH) before operation and at 4, 12, and 24 weeks after operation. CT three dimensional reconstuction was performed at 24 weeks after operation to evaluate the interbody fusion according to modified Brantigan grading. The specimens of L3, 4 were harvested for mechanical test, histological, and scanning electron microscope (SEM) observation at 24 weeks after operation. ResultsAll goats survived to the end of experiment. DSH at 4 weeks after operation increased when compared with preoperative one in each group, and then decreased;DSH was significantly lower at 12 and 24 weeks after operation than preoperative one in group C (P<0.05). There was no significant difference in DSH among 3 groups at preoperation and 4 weeks after operation (P>0.05);at 12 and 24 weeks after operation, DSH of groups A and B was significantly higher than that of group C (P<0.05), but no significant difference was found between groups A and B (P>0.05). CT three dimensional reconstuction showed that bony fusion was obtained in all goats of groups A and C, and in 3 goats of group B;according to modified Brantigan grading, the scores of groups A and C were significantlly higher than that of group B (P<0.05), but no significant difference between groups A and C (P>0.05). The biomechanical test showed that there was no significant difference in range of motion between group A and group B (P>0.05), which were significantly lower than that of group C (P<0.05). Microscopy and SEM observations showed that the interface between the Cage and vertebral body in group A was compact without obvious gap, and most conjunctive region was filled with osseous tissue;the interface was filled with soft tissue, and the connection was slack with obvious gap in some region in group B;the interface connection was compact, most region was filled with osseous tissue in group C. ConclusionThe interbody fusion with PHC Cage is effective in goat lumbar interbody fusion model. The interface connection is compact between the Cage and the host bone followed by micro-degradation of PHC Cage, but the long-term degradation need further observation.
Objective To observe the effect of cationic liposomal ceftazidime (CLC) combined with nano-hydroxyapatite/β-tricalcium phosphate (n-HA/β-TCP) in the treatment of chronic osteomyelitis of rabbits. Methods Thirty healthy New Zealand white rabbits (4-6 months old; weighing, 2-3 kg) were selected to prepare the chronic osteomyelitis models. After 4 weeks, the gross observation, X-ray examination, and bacteriological and histopathological examinations were done; the models were made successfully in 27 rabbits. Of 27 rabbits, 24 were randomly divided into 4 groups (n=6): only debridement was performed in group A; ceftazidime was given (90 mg/kg), twice a day for 8 weeks after debridement in group B; ceftazidime and n-HA/β-TC were implanted after debridement in group C; and CLC and n-HA/β-TCP were implanted after debridement in group D. Before and after treatments, X-ray examination was done, and Norden score was recorded. At 8 weeks after treatment, the specimens were harvested for gross observation and for gross bone pathological score (GBPS) using Rissing standard; half of the specimens was used for histological observation and Smeltzer scoring, the other half for bacteriological examination and calculation of the positive rate of bacteria culture. Results At 8 weeks after treatment, Norden score of group D was significantly lower than that of groups A, B, and C (P lt; 0.05), but no significant difference was found among groups A, B, and C (P gt; 0.05). At 8 weeks after treatment, sinus healed in groups C and D, but sinus was observed in groups A and B; the GBPS scores of groups C and D were significantly lower than those of groups A and B (P lt; 0.05). The Smeltzer scores of groups C and D were significantly lower than those of groups A and B (P lt; 0.05). The positive rates of bacteria culture of groups C (0) and D (0) were significantly lower than those of group A (25.0%) and group B (16.7%) (P lt; 0.05). Conclusion CLC combined with n-HA/β-TCP has good effect in treating chronic osteomyelitis of rabbits, and it has better effect in treating chronic osteomyelitis of rabbits than ceftazidime with n-HA/β-TCP.
Objective To develop the plastic nano-hydroxyapatite (nano-HA)/poly (3-hydroxybutyrate-hydroxyvalerate) polyethylene glycol(PHBV-PEG) gentamicin (GM) drug delivery system(DDS)(nano-HA/PHBV-PEG-GM-DDS) for treating osteomyelitis and find its releasing character in vivo. Methods The plastic nano-HA/PHBV- PEG-GM-DDS was prepared using nanoHAas the core carrier of GM, nano-HA with PHBV and PEG as coating and plastic fibrin glue(FG) as microsphere scaffold. The morphological features of nano-HA,drug loaded nano-HA and drug loaded nano-HA/PHBVPEG microsphere were examined by electron microscope.The GM concentration in blood, cortex bone and cancellousbone was detected at 12 different time points by the method of K-B after the plastic nano-HA/PHBV-PEGGM-DDS was implanted into the femora of 36 rabbits. Its GM releasing character was assayed in vivo. Results Nano-HA was similar to a blackjack, and its length was less than 60 nm. Drug loaded nano-HA appeared natural crystal condensate, of which surface adsorbed massive GM. The average grain diameter was 200.5 nm. Drug loaded nanoHA/PHBV-PEG microsphere had a shrinkable porous structure, of which surface configuration was consistent. The average grain diameter was 34.5 μm. The GM concentration and the antibacterial annulus was in the linear correlation. The correlation coefficient was 0.998. In cortex and cancellous bone tissue, the GM concentration was about 95.50±16.50 μg/ml and 80.20±13.80 μg/ml from the plastic nano-HA/PHBV-PEG-GM-DDS on the 1st day, then decreased gradually. After 56 days of operation, the GM concentration still exceeded the minimum inhibitory concentrationfor the staphylococcus aureus, but the peak level of serum GM concentration wasunder the nephrotoxicity concentration. Conclusion Plastic nano-HA/PHBV-PEG-GM-DDS was a good drug delivery system with sustained antibiotic effect in vivo. It was an effective method for the treatment of osteomyelitis.
【Abstract】 Objective To investigate the anti-infection and bone repair effects of cationic l i posome-encapsulatedvancomycin combined with the nano-hydroxyapatite/chitosan/konjac glucomannan (n-HA/CS/KGM) composite scaffold invivo. Methods Fifty-one 6-month-old New Zealand white rabbits, weighing 1.5-3.0 kg, were selected to prepare chronicinfectious tibia bone defect model by using Staphylococcus aureus. After 4 weeks, 48 survival rabbits were randomly divided into 4 groups (n=12). After debridement, defect was treated with nothing in group A, with n-HA/CS/KGM composite scaffold in group B, with vancomycin and n-HA/CS/KGM composite scaffold in group C, and with cationic l i posome-encapsulated vancomycin and n-HA/CS/KGM composite scaffold in group D. After 8 weeks of treatment, general observation, X-ray, HE staining, the bacterial culture, and the measurement of the longest diameter of bone defect were done. Results At 4 weeks after modeling, 48 rabbits were diagnosed as having osteomyelitis, including periosteal new bone formation, destruction of bone, and soft tissue swell ing. The Norden score was 3.83 ± 0.52. At 8 weeks after treatment, sinus healed in groups C and D, but sinus was observed in groups A and B; the gross bone pathologieal scores of group D were significantly better than those of groups A and B (P lt; 0.05). Bone defects were repaired completely in group D, the results of the longest diameter of bone defects in group D was significantly better than those in the other 3 groups (P lt; 0.05). New bone formation was observed in groups C and D, but periosteal reactionand marrow low-density shadow were observed in groups A and B; Norden score in group D was significantly better than those in groups A, B, and C (P lt; 0.05). HE staining showed that there were a large number of trabecular bone formation and fibrosis, with no obvious signs of infection in groups C and D, but neutrophil accumulation was observed in groups A and B; Smeltzer scores in groups C and D were significantly better than those in groups A and B (P lt; 0.05). Bacteriological results showed higher negative rate in groups C and D than in groups A and B (P lt; 0.05). Conclusion Cationic l iposome-encapsulated vancomycin and n-HA/CS/KGM composite scaffold can be a good treatment for infectious bone defects in rabbits, providing a new strategy for the therapy of bone defects in chronic infection.
Objective To evaluate the short-term effectiveness of nano-hydroxyapatite/polyamide-66 (n-HA/PA66) intervertebral cage for lumbar interbody fusion in the patients with lower lumbar degenerative diseases. Methods Between January and October 2011, 20 patients with lower lumbar degenerative diseases underwent transforaminal lumbar interbody fusion with n-HA/PA66 intervertebral cage. There were 8 males and 12 females, aged 22-80 years (mean, 51 years). The disease duration was 1 to 24 months (mean, 4 months). L4, 5 fusion was performed in 8 cases, L5, S1 fusion in 9 cases, and L4-S1 fusion in 3 cases. Among 20 cases, 3 were diagnosed as having recurrent lumbar disc protrusion, 5 as having lumbar degenerative spondylolisthesis, 9 as having lumbar isthmic spondylolisthesis, and 3 as having lumbar spinal stenosis. The intervertebral height and lordosis were measured on X-ray film to assess the surgical correction and postoperative sustain while osseous fusion was observed on 3-dimensional CT. The Oswestry disability index (ODI) and short-form 36 health survey scale (SF-36) scores were obtained to assess the status of clinical recovery. Results All patients had incision healing by first intention. The pain and numb were relieved in varying degrees after operation. No cerebrospinal leakage, nerve root injury, or wound infection was occurred. All patients were followed up 6-9 months (mean, 7 months). No cage displacement or collapse was found. The intervertebral height and lordosis of single fusion segment were significantly improved at 3 days and 3, 6 months after operation when compared with those at preoperation (P lt; 0.01); there was no significant difference among each time point after operation (P gt; 0.05). The fusion rate was 74% at 3 months after operation and 96% at 6 months after operation, with an average of 4 months (range, 3-9 months) for interbody fusion. The ODI and SF-36 scores were significantly improved at 3 days and 6 months after operation when compared with the scores at preoperation (P lt; 0.01); there was no significant difference among each time point after operation (P gt; 0.05). Conclusion The interbody fusion with n-HA/PA intervertebral cage is effective and safe to treat the lower lumbar degenerative diseases. The n-HA/PA66 intervertebral cage is an ideal device of interbody fusion with high fusion rate, low subsidence rate, and high transmission X-ray, but the long-term effectiveness need further observation.
Objective To investigate the effect of tissue engineering bone compounded in vitro by nanohydroxyapatite/collagen/ polylactic acid (nHAC/PLA) and recombinant human bone morphogenetic protein 2 (rhBMP-2) in repairing rabbit critical calvarial defects. Methods Forty eight New Zealand rabbits, weighting 2.0-2.5 kg, were made the models of critical cranial defects(15 mm in diameter) and divided into 4 groups randomly. Defects were repaired with autoflank bone in the positive control group; with no implant in the blank control group; with nHAC/PLA in the negative control; and with active nHAC/PLA(AnHAC/PLA) in the experimental group(the average quality of each AnHAC/PLA absorbed rhBMP-2 was 1.431 mg). The reapir results were observed through X-ray,HE dyeing and Masson’s trichrism dyeing after 8 and 16 weeks. Results The difference of bone formation was observed by X-ray block degree of skull defect area at 8 and 16 weeks. In the 8 th week and 16 th week, the radiopacities on cranial defect were 67.21%±2.06% and 86.48%±1.73% in the positive control group； 5.84%±1.92% and 9.48%±2.72% in the blank control group; 19.13%±2.51% and 35.67%±3.28% in the negative control group; and 58.84%±2.55% and 8561%±3.36% in the experimental group. There were significant differences between the negative control and the positive control group, and between the experimental group and the positive control group at 8 weeks(Plt;0.05) . There were significant differences between the negative control and blank group, and between the experiment and the blank group at 8 and 16 weeks(P＜0.05). The histology observation showed that the width of bone trabecula at 16 weeks was more than that at 8 weeks and bone defectwas full of bone tissue in positive control group. The bone defect was full of fibrous tissue at 8 and 16 weeks, and there was no new bone in the blank group. The bone defect was full of remnant material and fibrous tissue in the negative control group. The implanted area was replaced by the new bone at 8 weeks and the new bone was lamellar at 16 weeks in the experimental group; the residual material was less in defect area and there were more osteoblasts surrounding. Conclusion The nHAC/PLA is a good scaffoldmaterial of rhBMP-2 and AnHAC/PLA has agood ability in repairing bone defect. So it is hopeful to be applied in the clnical repair of large bone defect.
The present study is aimed to investigate the early clinical effects of nano-hydroxyapatite/polyamide 66 intervertebral fusion cage (n-HA/PA66 cage) for the treatment of lumbar degenerative diseases. We selected 27 patients with lumbar degenerative diseases who were managed by posterior decompression or reset operation combined with n-HA/PA66 cage intervertebral fusion and internal fixation from August 2010 to January 2012. The oswestry disability index (ODI), low back and leg pain visual analogue score (VAS), and intervertebral height (IH) were evaluated at preoperation, 1 week postoperation and the last follow-up period, respectively. Intervertebral bony fusion was evaluated at the last follow-up time. The patients were followed up for 12-24 months (averaged 19 months). The ODI, VAS and IH were significantly improved at 1 week postoperation and the last follow-up time compared with those at preoperative period (P<0.05). But there was no significant difference between 1 week postoperative and the last follow-up time (P<0.05). Brantigan's standard was used to evaluate fusion at the last follow-up time. There were 19 patients with grade 5 fusion, 8 with grade 4 fusion, with a fusion rate of 100%, and none with grade 1-3 fusions. There was no cage translocation and internal fixation breakage. These results suggested that n-HA/PA66 cage was an ideal biological material in the posterior lumbar interbody fusion and internal fixation operation for treatment of lumbar degenerative diseases. It can effectively maintain the intervertebral height and keep a high rate of bony fusion. The early clinical effect has been satisfactory.
【摘要】 目的 探讨纳米羟基磷灰石/聚酰胺66（nano-hydroxyapatite polyamide66，n-HA/PA66）颈椎融合器在颈椎间盘突出症前路手术重建中的临床疗效。 方法 2008年12月-2010年6月，对14例颈椎间盘突出症患者行前路椎间盘切除、椎管减压，以n-HA/PA66椎间融合器支撑植骨、钢板螺钉内固定治疗。随访时间3～12个月，平均6.3个月；随访时以日本矫形外科学会（Japan Orthopaedic Assoctiation， JOA）评分改善率评价患者神经功能恢复情况，复查X线片评估椎间融合器植骨融合情况，包括椎间高度及椎间融合器下沉情况。 结果 14例患者均成功完成颈椎前路减压手术以及椎间融合器的安放固定。所有患者术前症状均得到不同程度的改善，术后3、6、12个月的JOA改善率分别为87.0%、94.0%、97.0%。影像学检查显示所有患者植骨融合，椎间高度及椎间融合器的位置维持良好，无下沉、移位。 结论 n-HA/PA66颈椎间融合器具有早期支撑稳定功能，可有效维持颈椎椎间高度；术后植骨融合率高且便于X线片观察，是颈椎间盘突出症患者前路手术植骨的理想支撑材料，但长期效果需进一步随访观察。【Abstract】 Objective To evaluate the clinical effect of artificial cervical vertebra fusion apparatus of n-HA/PA66 in anterior reconstruction of cervical intervertebral disc herniation. Methods From December 2008 to June 2010, 14 patients with cervical intervertebral disc herniation underwent anterior cervical discectomy,spinal canal decompression,spinal canal decompression and reconstruction by n-HA/PA66 composite artificial vertebral body combined with plate instrumentation. The patients were followed up for 3 to 12 months with an average of 6.3 months. Neurological function was evaluated by improvement rate of JOA score and situations of the supporting body was observed by X-ray in 3,6,and 12 months after the surgery.The intervertebral height,the 1ocations, and the fusion rate of the supporting body were assessed in order to evaluate the stability of the cervical spine and alignment improvements. Results All the patients had undergone the operation successfully.The preoperative symptoms improved to varying degrees.JOA improvement rate were 87.0%, 94.0%, and 97.0% 3,6,and 12 months after the operation,respectively.Imaging studies showed that in all cases graft fusion were achieved,and cervical alignments,intervertebral height,cervical spine stability and the locations of the artificial vertebral body were well maintained.No displacement and subsidence of the artificial vertebral body occurred. Conclusion n-HA/PA66 artificial vertebral body can provide early cervical spine support and stability and cervical intervertebral height.It has a high rate of graft fusion and is convenient to observe by X-ray.Therefore,n-HA/PA66 can be taken as an ideal graft for anterior degenerative cervical spine operation,but further follow-up study is still needed to evaluate the long-term effects.
Objective To assess the mid-term effectiveness of anterior decompression and fusion with nano-hydroxyapatite/polyamide 66 (n-HA/PA66) cage in treatment of cervical spondylotic myelopathy. Methods A retrospective study was made on 48 patients with cervical spondylotic myelopathy who underwent anterior decompression and fusion with n-HA/PA66 cage between August 2008 and January 2010. There were 33 males and 15 females with an average age of 54.5 years (range, 42-72 years). The disease duration was 3-12 months (mean, 6 months). The affected segments included 35 cases of single segment (C3, 4 in 7, C4, 5 in 18, and C5, 6 in 10) and 13 cases of double segments (C3-5 in 7 and C4-6 in 6). Of 48 patients, 28 was diagnosed as having intervertebral disc protrusion, 12 as having ossification of posterior longitudinal ligament, and 8 as having vertebral osteophyte; 35 patients underwent single segmental anterior corpectomy and fusion, and 13 patients underwent single segmental anterior discectomy and fusion. The pre- and post-operative radiographs (cervical anteroposterior and lateral X-ray films and three-dimensional CT scans) were taken to measure the segmental height and lordosis angle. Brantigan et al assessment standard and visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) scores were used to evaluate the graft fusion and the improvement of clinical symptoms, respectively. Results All patients were followed up for 46 months on average (range, 36-54 months). No cage breaking, displacement, or sliding was found. At last follow-up, 36 cases were rated as Brantigan grade E, 10 cases as grade D, and 2 cases as grade C; the fusion rate was 96%. Both segmental height and lordosis angle were corrected significantly at immediate and 6 months after operation and last follow-up than those before operation (P lt; 0.05), but no significant difference was found among different time points after operation (P gt; 0.05). At last follow-up, the cage subsidence was (1.3 ± 1.0) mm. The VAS and JOA scores at 6 months after operation and last follow-up were significantly improved when compared with preoperative scores (P lt; 0.05), and the scores at last follow-up were superior to ones at 6 months after operation (P lt; 0.05). Conclusion The mid-term effectiveness of anterior decompression and fusion with the n-HA/PA66 cage in patients with cervical spondylotic myelopathy is satisfactory because it can effectively restore and maintain segmental height and lordosis angle and promote osseous fusion.
ObjectiveTo explore the effectiveness of nano-hydroxyapatite/polyamide-66 (n-HA/PA66) Cage in interbody fusion for degenerative lumbar scoliosis.MethodsA 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.ResultsThere 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 (P<0.05). At last follow-up, the intervertebral height in double-level group was superior to which in single-level group (P<0.05). The coronal Cobb angles after operation significantly improved compared with preoperative ones (P<0.05), and no significant difference was found between 2 groups at each time point (P>0.05). 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 (P<0.05). The VAS score in double-level group was higher than that in single-level group (P<0.05) at last follow-up, and no significant difference was found in VAS score and modified ODI between 2 groups at other time points (P>0.05). 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.ConclusionThe 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.