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<p><b>OBJECTIVE</b>To analyze the risk factors of surgical site infection (SSI) following posterior lumbar intervertebral fusion.</p><p><b>METHODS</b>This retrospective case-control study was conducted in 2904 patients undergoing posterior lumbar intervertebral fusion from 2011 to 2016. Forty-three patients with SSI within 30 days after the operation served as the case group, and 334 randomly selected patients without infection served as the control group. Age, gender, diabetes, body mass index (BMI), albumin level, multilevel procedures, subcutaneous fat thickness, surgery duration and the percentage of lumbar multifidus muscle fat infiltration were analyzed, and univariate and multivariate logistic regression analyses were performed to identify the risk factors of SSI.</p><p><b>RESULTS</b>Multivariate logical regression analysis identified a female gender, subcutaneous fat thickness, multilevel surgery, and lumbar multifidus muscle fat infiltration as significant risk factors for SSI ( < 0.05). BMI was not correlated with fat infiltration in the lumbar multifidus muscle ( > 0.05).</p><p><b>CONCLUSIONS</b>A female gender, multilevel surgery, subcutaneous fat thickness and fat infiltration in the multifidus muscle are related to SSI following posterior lumbar intervertebral fusion. Fat infiltration in the multifidus muscle was a spine-specific risk factor for SSI independent of BMI.</p>
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Objective To perform digital 3D measurement of anatomic parameters associated with vertebral units fixed by ribs and pedicle fixation of T4-T10,providing evidence for clinical application.Methods Spiral CT scan of T4-T10 vertebrae was conducted in 15 normal adults without spinal disorder.The data were imported into computer to establish units and disc models of thoracic and rib vertebrae T4-T10 using Mimics 16.0 software and Ansys 11.0 finite element software.The following data were measured in the vertebral pedicle-rib unit fixation group (group A) by software:transverse diameter of vertebral pedicle-rib unit,length of the outside pedicle screw,inclination angle of pedicle screw,and maximum and minimum inclination angles of pedicle screw;the following data were also measured in the pedicle fixation group (group B) by software:pedicle transverse diameter,length of pedicle screw,inclination angle of pedicle screw,and maximum and minimum inclination angles of pedicle screw.The corresponding parameters were compared between groups A and B.Results In both groups,the transverse diameters and screw lengths gradually increased with the increase in the vertebral sequence while the inclination angle of pedicle screw,and maximum and minimum inclination angles of pedicle screw decreased with the increase in the vertebral sequence.All the parameters in groups A were significantly larger than the corresponding ones in group B (P ＜ 0.05).Conclusions Of the spinal segment of T4-T10,the rib vertebral unit fixation can provide greater safe screw angles and screw diameters for clinical surgery.This is of vital significance for reducing the surgical complexity and improving screw prehension.
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BACKGROUND:In recent years, neural stem cels are considered to be ideal for the treatment of spinal cord injury, but the proportion of its natural differentiation into neurons in the host body is relatively low, which severely restricts the therapeutic effect on spinal cord injury. OBJECTIVE:To investigate the effect of erythropoietin on the differentiation of neural stem cels in vitro. METHODS:Under sterile condition, neural stem cels from the hippocampus of neonatal Wistar rats were isolated, cultured and identified by immunofluorescencein vitro. The third generation of neural stem cels were randomly divided into 0.5, 5, 50 U/mL erythropoietin groups and control group (with no erythropoietin). RESULTS AND CONCLUSION:Compared with the control group, the differentiation rate of neural stem cels was significantly improved in the 0.5, 5, 50 U/mL erythropoietin groups (P 0.05). These findings indicate that erythropoietin can effectively induce the differentiation of neural stem cels into neurons in vitro, and moreover, it can significantly improve the differentiation rate of neural stem cels into neurons.
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BACKGROUND:At present,there is lack of relevant biomechanical model for the T6-T7-T8 rib-vertebral fix unit.In addition,there is no support of parameters of basic studies on reasons and reasonable explanation of screw breakage,poor quality of bone fusion and adjacent segment degeneration.OBJECTIVE:To develop a three-dimensional finite element model of bone graft with vertebral tuberculosis debridement and posterior rib-vertebral unit fixed system through tuberculosis of thoracic spine (T6-8),and to analyze the stress so as to improve it.METHODS:Spiral CT data of one male patient (172 cm,71 kg,39-year-old) with T7 vertebral tuberculosis were imported into computer to develop a three-dimensional finite element model of bone graft with vertebral debridement and posterior vertebral unit fixed system through tuberculosis of T6-8 by Mimics 13.0 and Ansys 11.0 finite element software.500 N pressure and 10 N?m torque were loaded to the vertebral body by 3 kinds of physiological loads which simulated flexion,extension and lateral bending.The stress distribution of fixation devices under different loads was compared.RESULTS AND CONCLUSION: At the positions of anteflexion and extension,the stress mainly concentrated to screw tail,and the stress of upper screw was greater than the middle and lower screws.For connecting rods,the stress of the middle was always less than the lower middle and the middle stress was zero.At lateral bending position,the stresses of upper and middle screw tail were quite,and the unilateral stress of connecting rod was also equivalent.For three different dynamics at the same point,the stress of middle connecting rod increased in the lateral bending motion,and the stress of lower screw tail was equivalent.These data suggested that it is prone to fatigue fracture at upper screw tail by bone graft with vertebral tuberculosis debridement and posterior rib-vertebral unit fixed system through tuberculosis of thoracic spine (T6-8) at the three positions of anteflexion,extension and lateral bending.The lower connecting rod at the positions of anteflexion and extension and the middle connecting rod at the position of lateral bending easily cause fatigue fracture.
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BACKGROUND:A newly developed calcium phosphate/β-tricalcium phosphate composite bone cement with a negative surface charge (genex?) has been reported to possess osteoinductivity properties. However, to our knowledge, no previous literatures have reported genex? for vertebroplasty in the osteoporotic spine. OBJECTIVE:To evaluate the biomechanical properties and osteogenesis of vertebral bodies injected with genex? cement in a rabbit vertebroplasty defect model. METHODS:Thirty New Zealand rabbits were used to establish osteoporosis models. Four weeks after modeling, model rabbits had an iatrogenical y created cavitary lesion at L 3 and L 5 and were injected with either genex? cement (experimental group) or polymethyl methacrylate bone cement (control group). The L 1 vertebral body served as model group without treatment. After 3 and 6 months, 15 rats from each group were executed respectively, and three vertebral samples were taken for Micro-CT analysis and biomechanical tests. RESULTS AND CONCLUSION:(1) The Micro-CT showed better three-dimensional structure parameters of the trabecular bone in the experimental group than the control group (P0.05). After 6 months, the structure parameters in the experimental group were superior to those in the control and model groups (P0.05), but stil higher than that of the model group (P0.05). These findings indicate that genex? cement can rapidly repair osteoporotic vertebral defects and improve the bone strength. Verterbroplasty with genex? cement has adequate osteoinductivity, biocompatibility, and adequate compressive strength.
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<p><b>OBJECTIVE</b>To compare the clinical efficacy and safety of percutaneous vertebroplasty by unipedicular and bipedicular approach for treatment of Kummell's disease.</p><p><b>METHODS</b>The clinical data of patients with Kummell's disease undergoing percutaneous vertebroplasty via unilateral or bilateral approach between January, 2006 and January, 2011 were reviewed. The clinical efficacy, operation time, bone cement injection volume, incidence of cement leakage, degree of vertebral height restoration, and degree of kyphosis correction were compared between the patients receiving surgery via the two approaches.</p><p><b>RESULTS</b>The operation time was shorter in the unipedicular group than in the bipedicular group (P<0.05), but bone cement injection volume, incidence of cement leakage, degree of anterior vertebral height restoration, degree of middle vertebral height restoration, degree of kyphosis correction, and VAS scores were all comparable between the two groups (P>0.05). In both groups, the VAS scores at 24 h, 3 months and at the last follow-up after the surgery were lowered compared to the preoperative scores (P<0.05).</p><p><b>CONCLUSION</b>Both unipedicular and bipedicular percutaneous vertebroplasty can achieve satisfactory analgesia in the treatment of Kummell's disease with similar clinical efficacy. The unipedicular approach is sufficient for treatment of Kummell's disease.</p>
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Humans , Bone Cements , Spinal Fractures , General Surgery , Spine , Treatment Outcome , Vertebroplasty , MethodsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the structural characteristics and biocompatibility of a novel nano-Ta-Ti alloy rod for its potential application in internal fixation.</p><p><b>METHODS</b>Ta coating of a Ti alloy rod with nano-Ta (tantalum) powder was performed using laser melting with symmetrical grooves repleted with nano-Ta powder along the whole length. The microstructure of the cross section of Ta-Ti alloy rod, pore diameter and components of the coating were analyzed using scanning electron microscopy. The influence of this nano-Ta-Ti alloy on proliferation and differentiation of MC3T3-E1 cells was evaluated by MTT cytotoxicity test and ALP activity test.</p><p><b>RESULTS</b>Under scanning electron microscope, the Ta-coating surface presented with a gross porous (200-300 µm) structure with dense fusion between Ta particles, and no new element was produced after laser melting. Biocompatibility evaluation showed that Ti alloys with and without Ta coating both promoted the proliferation of MC3T3-E1 cells, but the coated alloy showed better performance and obviously promoted the differentiation of the osteoblasts.</p><p><b>CONCLUSION</b>Alloying between Ta and Ti can be accomplished successfully by laser melting technique, and the alloy obtained has ideal surface structure and good biocompatibility.</p>
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Animals , Mice , 3T3 Cells , Alloys , Biocompatible Materials , Cell Differentiation , Cell Proliferation , Materials Testing , Microscopy, Electron, Scanning , Osteoblasts , Cell Biology , Porosity , Tantalum , TitaniumABSTRACT
<p><b>OBJECTIVE</b>To assess the effect of intermittent subcutaneous injections of signal-selective parathyroid hormone (PTH) peptide analog on fracture healing in orchiectomized mouse models.</p><p><b>METHODS</b>Thirty-six 7-week-old C57/BL male mice were orchiectomized and injected with hPTH(1-34), the signal-selective PTH peptide analog [Gly(1), Arg(19)]hPTH (1-34), or an identical volume of vehicle 1 week after induction of femoral fracture. At 14 and 28 days after the operation, the mice were sacrificed for measurement of bone mineral density (BMD) and bone mineral content (BMC) of the callus using by dual energy X-ray absorptiometry. The bone healing was evaluated by radiography, biomechanical testing, micro-computed tomography (Micro-CT) and histological examination.</p><p><b>RESULTS</b>At 14 days after the operation, BMD in PTH peptide analog group was significantly increased (P<0.05). The mouse models treated with the PTH peptide analog showed significantly lower ultimate bending force and bending rigidity than those with hPTH(1-34) treatment. X-ray and Micro-CT scanning showed that callus transformation and remodeling was better in PTH peptide analog group than in the vehicle control group but poorer than in hPTH(1-34) group.</p><p><b>CONCLUSION</b>The signaling-selective PTH peptide analog G1, R19 (1-28) can accelerate fracture healing in orchiectomized mouse models, in which process cAMP/PKA pathway plays an important role.</p>
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Animals , Male , Mice , Bone Density , Fracture Healing , Mice, Inbred C57BL , Orchiectomy , Parathyroid Hormone , Pharmacology , Signal TransductionABSTRACT
<p><b>OBJECTIVE</b>To evaluate the biomechanical properties of geneX cements for use in vertebroplasty in a calf osteoporotic vertebral compression fracture model.</p><p><b>METHODS</b>Thirty vertebral bodies (T(9)-L(4)) were harvested from 4 fresh calf spines. The bone mineral density was measured with dual-energy radiographic absorption. Osteoporotic vertebral model was induced in each vertebra using decalcifying chemical agents, and was then compressed to determine their initial strength and stiffness before injecting the cement. Thirty vertebral bodies were divided randomly into geneX(®) cement group, CSC group, and PMMA group. The fractures were repaired using a transpedicular injection of cements and re-compressed to measure posttreatment strength and stiffness.</p><p><b>RESULTS</b>The normal mean BMD of the calf vertebra was 1.425∓0.072 g/cm(2), which was reduced significantly to 1.074∓0.065 g/cm(2) after decalcification. The mean injected volume was similar between geneX(®) (4.5∓0.7 ml), CSC (4.3∓0.8 ml) and PMMA (3.8∓0.4 ml) groups. The vertebral strength was restored after the treatment to 1198∓529 N in geneX(®) group, 1212∓430 N in CSC group and 1672∓704 N in PMMA group. All the cements produced significantly greater strength than the initial strength (P<0.05). The augmented strength in geneX(®) and CSC groups were similar (P>0.05), but both were significantly less than that in PMMA group (P<0.05). The stiffness in geneX(®), CSC, and PMMA groups was 233∓130, 242∓191, and 323∓145 N/mm, respectively, showing no significant difference between them (P>0.05). No significant difference was found in the augmented stiffness among the 3 cements (P>0.05).</p><p><b>CONCLUSION</b>geneX(®) cement is a useful alternative to PMMA in vertebroplasty for osteoporotic vertebral compression fractures, but further study is needed to evaluate its biosorption in vivo.</p>
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Animals , Cattle , Biomechanical Phenomena , Bone Cements , Therapeutic Uses , Disease Models, Animal , Fractures, Compression , General Surgery , Lumbar Vertebrae , Wounds and Injuries , Osteoporosis , Pathology , Thoracic Vertebrae , Wounds and Injuries , VertebroplastyABSTRACT
Objective To investigate the causes and prevention strategies of postoperative spinal cord injury after anterior approach surgery for cervical spondylotic myelopathy. Methods The clinical data of 749 patients with cervical spondylotic myelopathy treated with anterior approach surgery from 2001 to 2009 were retrospectively studied.There were five patients with spinal cord dysfunction instantly or early after operation,including three males and two females at average age of 52 years (range,48-62 years).Two patients were combined with ossification of the posterior longitudinal ligament.The Japanese Orthopaedic Association (JOA) score was average 12.4(9-16)preoperatively.The surgeries included anterior cervical diskectomy(or corpectomy)and interbody fusion(iliac bone graft or cage or titanium mesh)and locking plates fixation.The blood loss was 50-200 ml.The symptoms included instant spinal cord injury in two patients,loss of the motor and feeling of both legs at 6 h after surgery in one,paralysis of one side limbs at 24 h after surgery in one and numbness of limbs at 5 days after surgery in one.Four patients were treated by large dose of methylprednisolone.Five patients underwent anterior exploration surgery,of which one patient received posterior cervical one-door expansive laminoplasty. Results The patients were followed up for average 16 months(12-24 months).The JOA score of four patients was recovered at three months and WaS better than preoperation after surgery.The function of spinal cord of one patient showed no improvement at one year after surgery.The causes for spinal cord injury included inappropriate surgical manipulation in decompression and haemostasis in two patients,insufficient decompression in one,epidural hematoma in one and absorbable hemostatic gauze in one. Conclusions The major causes of postoperative spinal cord injury in anterior approach surgery for cervical spondylofic myelopathy are the delayed postoperative injury.The spinal cord can recover to normal and has satisfactory prognosis if discovered promptly.We must avoid the spinal cord injury by surgical Manipulation that may result in permanent neurological deficits.
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Objective To investigate the effects of nitric-oxide synthase inhibitor on matrix metalloproteinases (MMPs) expression in osteoarthritis (OA) cartilage by Luminex analysis,and to explore the mechanism of nitric-oxide synthase inhibitor on modification of the metabolism of OA cartilage.Methods Fifteen specimens of articular cartilage taken from the patients with OA were cultured and divided in two groups.The control group was those with no intervention.L-NIL group was co-cultured with NOS inhibitor L-NIL.After 72 h cultivation,the release of NO and the activity of NOS on OA cartilage were measured by Griess reaction and spectrophotometric methods.MMPs (MMP-1,MMP-2,MMP-3,MMP-9,MMP-13) expression was measured by Luminex analysis.Comparisons between groups were performed with paired sampies t test.Results After cultured for 72 h,spectrophotometric analysis showed high concentration of NO release[(216±47) μmol/L ] and high level of active NOS [(5.7±1.3)U/ml]in supernatants of the control,1 mmol/L concentration L-NIL could evidently reduce NO release [(55±20)μmol/L,P<0.01] and NOS activity [(1.7±0.7)U/ml,P<0.01 ].Luminex analysis demonstrated high MMP-1,MMP-2,MMP-3,MMP-9,MMP-13 expression in cartilages of the control group [respectively for (10.8±5.4)ng/ml,(9.2±3.3) ng/ml,[11.6±4.2 )ng/ml,(1.27±1.07)ng/ml,(3.6±1.3)ng/ml] and 1 mmol/L concentration L-NIL could evidently inhibit MMP-1,MMP-2,MMP-3,MMP-9,MMP-13 expression [respectively for (3.6±1.8)ng/ml,(2.3±1.2)ng/ml,(3.6±1.4)ng/ml,(0.65±0.21)ng/ml,(1.8+0.5)ng/ml,P<0.05 ].Conclusion Luminex analvsis has shown that NOS inhibitor can reduce NO release and NOS activity and modify metabolism of articular cartilage by inhibiting the over-expression of MMPs.
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<p><b>OBJECTIVE</b>To explore the variety of the genetic polymorphism of eight Prunella germplasm resources by AFLP analysis.</p><p><b>METHOD</b>The amplified fragment length polymorphism (AFLP) tags were applied to screen out 32 selective amplification primer pairs, the amplified bands as original matrix were analyzed with NTSYS-PC software for the similarity between the Prunella germplasm and the construction of genetic phylogenetic tree.</p><p><b>RESULT</b>SDS extraction of genomic Prunella DNA showed a good quality, could meet the requirements of AFLP analysis. From 32 selective amplification primer pairs, 10 pairs with strong polymorphism, better band and higher resolution were used for the construction of the AFLP Prunella fingerprint, all eight Prunella germplasms were separated, they were divided into 3 categories.</p><p><b>CONCLUSION</b>Prunella germplasm resources are rich in genetic diversity, certain morphological characteristics and differences are associate with genotype.</p>
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Amplified Fragment Length Polymorphism Analysis , DNA, Plant , Genetic Variation , Polymorphism, Genetic , Prunella , Classification , GeneticsABSTRACT
BACKGROUND: The reaction of osteoblasts is important role in the reconstruction of osteocytes, and the mechanism of bone remodeling can be known from the cytological level through analyzing the mechanical reaction of osteoblasts under different loading.OBJECTIVE: To analyze the effects of low frequency vibration on the proliferation and differentiation as well as the matrix excretion of cultured human osteoblasts.DESIGN: A comparative observation.SETTING: Department of Orthopaedics, Nanfang Hospital of Southern Medical University.MATERIALS: The experiment was carried out in the laboratory of Nanfang Hospital from January to December in 2002. Human osteoblasts were isolated from the iliac cancellous bone of adults.METHODS: The osteoblasts were cultured for 48 hours, and then treated with low frequency vibration of 0.1, 0.2, 0.5, 2 and 5 Hz. The proliferation of the osteoblasts was detected with flow cytometry, and the activity of alkaline phosphatase (ALP) and content of osteocalcin were assayed by spectrophotometric methods and radioimmunoassay respectively.MAIN OUTCOME MEASURES: ① Effects of low frequency vibration on the ALP activity and osteocalcin excretion of osteoblasts; ② Effects of low frequency vibration on the proliferation of osteoblasts detected with flow cytometry.RESULTS: ① 0.2 and 0.5 Hz vibrations could markedly increase the ALP activity of osteoblast (P ＜ 0.01), but that of 5 Hz obviously decreased the ALP activity (P ＜ 0.01). 0.1 and 2 Hz vibrations had no obvious effects on the ALP activity of osteoblasts. ② 0.2 and 0.5 Hz vibration could significantly increase number of osteoblasts at S phase from 10.4% to 12.45% and 16.12%, and the proliferative index increased from 20.14% to 26.21% and 28.75%; 0.1 and 2 Hz vibration has not obvious effects in osteoblast proliferation index; 5 Hz vibration obviously decreased the proliferative index value to 13.22% (P ＜ 0.05). 0.1 and 2 Hz vibrations had no obvious effects on the proliferative index of osteoblasts (P ＞ 0.05). ③ 0.2 and 0.5 Hz vibrations could obviously increase the amount of osteocalcin excretion to 1.87 μg/L and 2.47 μg/L(P ＜ 0.05), but 2 and 5 Hz vibrations decrease the amount of osteocalcin excretion (P ＜ 0.05), and that of 0.1 Hz had no obvious effect on amount of osteocalcin excretion (P ＞ 0.05).CONCLUSION: Low frequency vibrations of 0.2-0.5 Hz could accelerate the proliferation and differentiation as well as the excretions of active materials of osteoblasts, and it plays an instructive role for low frequency vibration to treat fracture.
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0.05).Microscopic morphology has also been observed, no visible damage could be found in the structure of lenses from eyes injected with ouabain (figs 3 and 4). Serial sections of paraffin-embedded lenses show that the number of fiber cells increased significantly in experimental samples treated with ouabain at a concentration of 0.1 ?M(table 4, P