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Occipitocervical anatomy is characterized by deep location, complex structure, and unique function. The motor function of the occipitocervical region is highly flexible. How to achieve satisfactory spinal cord decompression with minimal invasion and how to effectively reconstruct biomechanical stability and maintain flexible motor function are important clinical problems that need to be solved urgently. However, this has also led surgeons to focus too much only on surgical techniques rather than comprehensive understanding and treatment of the disease. There are three common but easily ignored issues in clinical practice: Firstly, the importance of occipitocervical anatomy research to improve clinical diagnosis and treatment. The stability of the base of the skull and the lower cervical vertebra should also be considered in clinical diagnosis and treatment. Secondly, atlanto-occipito-atlantoaxial joint and local ossification of the posterior longitudinal ligament. Atlantoaxial flexibility may lead to the earliest appearance of partial ossification of the posterior longitudinal ligament in this region. Thirdly, atlanto-occipito-atlantoaxial joint osteoarthritis is often neglected, and paying attention to the diagnosis and treatment of atlanto-occipito-axial joint osteoarthritis will improve the overall curative effect of occipito-cervical diseases.
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Cervical hyperextension injury is a common special type of cervical spinal cord injury. While several problems should be further understood in clinical practice. Why do some seemly slight hyperextension forces cause such severe cervical spinal cord injury? Why do the cervical spinal cord hyperextension injuries show various and different manifestations? Why does the intrinsic muscle function of the hand of patients with hyperextension cervical spinal cord injury recover slowly or even fail to recover? How can we tell the differences between injury mechanisms of hyperextension and whiplash injury of cervical spine? Why is the surgical intervention always necessary to be performed for cervical hyperextension injury? The author discusses the above problems encountered by clinicians to strengthen the understanding of the disease, and hopes to provide some information for the clinical diagnosis and treatment.
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Objective To investigate the imaging characteristics and pathogenic manifestations of thoracic ossification of the ligamentum flavum complicated with dural ossification.Methods CT and MRI imaging data of 62 segments from 29 patients with thoracic ossification of the ligamentum flavum (TOLF) treated with "en bloc resection of lamina and ossified mass" were retrospectively analyzed.There were 19 males and 10 females,aged 54.9±10.25 years (36-77 years),16 segments in 11 cases with dural ossification (DO) and 46 segments in 18 cases without DO.The ossified mass shape,the relationship between ossified mas and dura mater on cross section of CT bone window and MRI T2WI,and the ossified mass occupational rate (OR) of the spinal canal were investigated.Pathologic features of TOLF-DO from 2 patients were analyzed by H&E staining.Results The shape of ossified mass was as followed,in 16 segments with DO,7 segments (43.8％) by CT and 2 segments (12.5％) by MRI showing ossification layer on the dural sac side of ligamentum flavum;1 segment (6.3％) by CT and 2 segments (12.5％) by MRI showing typical Tram track sign.The relationship between ossified mass and dura mater was that 7 segments (43.8％) by CT and 7 segments (43.8％) by MRI with "C" sign and 7 segments (43.8％) by CT and 8 segments (50.0％) by MRI with "V" sign.The ossified mass OR was 60.5％± 13.0％ in the group with DO and 42.2％± 12.3％ in the group without DO.There was a significant difference between the two groups (t=5.192,P＜0.001).Among the 16 segments with DO,the ossified mass OR of 7 segments with "C" sign was 68.8％± 12.8％ and that of the other 9 segments without "C" sign was 54.39％±9.9％.There was significant difference between the two groups (t=2.45,P=-0.028).Histological examination showed that there were two pathological phenomena in the dura tissue adjacent to ossified mass.The one,there were fibrocartilage,cartilage and osteogenesis in the dura mater.The other,the unossified dura mater fused with the ossified mass but with clear histological demarcation,while the dura mater on the ventral side of the ossified ligamentum flavum atrophies or disappeared.Conclusion The occurrence of dural sac ossification is associated with the ossification of ligamentum flavum beginning at the side of the dural sac and the persistent thickening of the ossified mass.The pathological manifestations of DO are ossification of dural tissue or fusion of dural with ligamentum flavum ossification.
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Objective To investigate the clinical effect of anterior controllable antedisplacement and fusion (ACAF) for the treatment of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine.Methods The data of 45 cases with cervical posterior longitudinal ligament ossification treated by ACAF from March 2017 to October 2017 were retrospectively analyzed,including 25 males and 20 females,age 45-68 years,average 57.5 years.There were 18 cases involving C3 vertebral body,30 cases involving C4 vertebral body,40 cases involving C5 vertebral body,34 cases involving C6 vertebral body,and 7 cases involving C7 vertebral body.The function of the neural function was evaluated by the Japanese Orthopaedic Association (JOA) scoring system at preoperation and latest follow-up.The curvature of the cervical spine was measured on the lateral X-ray film of the cervical spine,the maximum occupying ratio of the spinal canal was measured on the cross section of the CT scan,and compression of the cervical spinal cord was evaluated by the cervical MRI.Results Patients were followed up for 3 to 6 months (average,3.9 months).The improvement of neurological function was obtained in all the patients.The JOA score improvement rate at the latest follow-up was 71.3％±9.6％.The cervical lordosis was improved from preoperative 4.5°±3.8° to 10.3°±4.8° at the latest follow-up.The canal stenosis ratio was decreased from preoperative 54.3％±8.2％ to 12.5％±5.3％ at the latest follow-up.MRI showed that the cervical spinal cord was adequately decompressed in situ.No specific complications were identified that were associated with this technique.Conclusion The present study elaborates the surgical tips and demonstrates the satisfactory outcome of ACAF for the treatment of OPLL.This novel technique has the potential to serve as an alternative surgical technique for the treatment of cervical OPLL.
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Objective To evaluate theclinical efficacy and safety of anterior cervical ossified posterior longitudinal ligament en bloc resection (ACOE),and analyze the advantages of ACOE compared to the traditionally anterior cervical surgery.Methods The clinical datawith more than one year follow-up of 96 patients suffered from cervical ossification of the posterior longitudinal ligament(OPLL) from April 2010 to March 2017 was retrospectively analyzed,including 57 males and 39 females,aged 32-69 years,average 54.6±8.7 years.There were 29 cases of nodular type (30.2％),48 cases of segmental type (50.0％),5 cases of continuous type(5.2％),and 14 cases of mixed type (14.6％).The neurological function assessments before and after operation were performed using the Japanese Orthopaedic Association (JOA) scoring system and the visual analogue scale (VAS) scoring system.The effect of ossified mass resection was observed by three-dimensional reconstruction CT scan.The spinal cord decompression was evaluated by MRI.The cervical curvature was compared before and after surgery by cervical lateral radiograph.The operation time,intraoperative blood loss,recovery rates of the JOA scores and complication rates of this group were compared with the cases of anterior cervical ossified posterior longitudinal ligament piecemeal resection (ACOP) reported by the recent literature to analyze the clinical efficacy,safety and advantages of ACOE.Results All the surgeries of 96 cases were successfully performed,including 57 cases (59.4％) with subtotal resectionof single vertebra,31 cases (32.3％) with subtotal resectionof doublevertebras,1 case (1.0％) with expanded intervertebral decompression,4 cases (4.2％) with "vertebra + semi-vertebra" subtotal resection,1 case (1.0％) with "semi-vertebra + vertebra + semi-vertebra" subtotal resection,2 cases with "double vertebras + semi-vertebra" subtotal resection (2.1％).Ninty-six cases were followed up for 12 to 78 months,with an average of 28.0±9.3 months.The preoperative JOA score with (11.38±2.80) scores was increased to 15.32± 1.62 scores at the last follow-up,and the recovery rate of JOA score was 74.63％±13.18％.The preoperative VAS score with 6.00±1.41 scores was reduced to 2.35±1.11 scores at the last follow-up.The cervical curvature increased from 10.4°±9.0° before surgery to 15.8°±8.1° at the last follow-up.CT showed that the ossified masses of the surgical segments were completely excised without residue;MRI showed that the compressionsof spinal cords and dural sacs were completely relieved,with nice morphology recovery.There was no neurological deterioration in this group.There were 6cases of cerebrospinal fluid leakage (CSFL),3 cases of C5 nerve palsy,1 case of Hornersyndrome,2 cases of dysphagia and hoarseness,1 case of titanium mesh subsidence with screw loosing.At the final followups,except one case of occasional throat foreign body sensation,the above complications were all remittedat different followup periods.Compared with the cases of ACOP reported by the recent meta-analysis,the operation time,the intraoperative blood loss,the complication rate of dysphagia with hoarseness and neurological deterioration were lower than those reported in the literature.The recovery rate of JOA scorewas higher than which reported in the literature.Conclusion ACOE is safe and effective for the treatment of cervical OPLL,which may be superior to traditional anterior cervical surgery in terms of surgical safe-ty,controllability of cerebrospinal fluid leakage and improvement of neurological function.
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BACKGROUND: Autologous platelet-rich plasma (PRP) is a concentrate of platelet-rich plasma protein derived from autologous whole blood. The activated platelets can release a large number of high concentrations of growth factors and bioactive substances, which provides a theoretical basis for its application in various disciplines and fields. At the same time, autologous PRP has been popularized because it will not cause immune rejection with extensive sources, easy to extract and low cost.OBJECTIVE: To summarize the preparation method and performance of autologous PRP, and to explore its latest research results and underlying mechanisms in spinal surgeries.METHODS: A computer-based online retrieval of CNKI and PubMed databases was performed for articles concerning autologous PRP used in spinal surgeries. Finally, 42 eligible literatures were included according to the inclusion and exclusion criteria.RESULTS AND CONCLUSION: (1) Autologous PRP is rich in a variety of growth factors and bioactive substances, so it has been used in the fields of disc repair, bone conduction and osteoinduction, and its effectiveness has been confirmed through abundant basic and clinical trials. (2) Meanwhile, autologous PRP also is used for tissue repair and skin regeneration, such as spontaneous cerebrospinal fluid leakage and pressure ulcer. (3) Notably, autologous PRP has shown a promising prospect in the field of spinal surgeries.
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Objective To report a novel technique named anterior controllable antedisplacement and fusion (ACAF) for the treatment of severe ossification of the posterior longitudinal ligament of the cervical spine,which allows for direct decompression of the nerve without resection of the ossification,making up for deficiencies in traditional anterior or posterior decompression.Methods The main surgical procedures of the ACAF included treatment of intervertebral space,removal of the anterior part of vertebrae,installation of titanium plate and interbody fusion cages,bilateral osteotomies of the vertebrae,and antedisplacement of the vertebrae ossification complex.The clinical data of two patients undergoing this surgery for severe ossification of the posterior longitudinal ligament of cervical spine were collected and analyzed.Results ACAF enabled direct decompression of spinal cord and nerve root through antedisplacement of the vertebrae ossification complex.The two patients who underwent ACAF gained satisfactory restoration with decompression of spinal cord and good recovery of neurological function,with no specific complications.Conclusion ACAF surgery takes into account the effectiveness of anterior direct decompression and the safety of posterior indirect decompression.Preliminary results shows that it can be used for severe cervical ossification of the posterior longitudinal ligament.
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BACKGROUND:Current studies on the pathogenesis of ossification of the ligamentum flavum are stil in a preliminary stage, and any single factor influencing incidence of ossification of ligamentum flavum cannot completely explain the pathogenesis of this disease. OBJECTIVE:To summarize the pathogenesis of ossification of ligamentum flavum. METHODS:A computer-based online search was conducted in PubMed, Wanfang, and CNKI databases from January 1990 to December 2015 to screen the relevant literatures regarding the pathogenesis of ossification of the ligamentum flavum using Chinese and English key words“ossification of ligamentum flavum, basic research, pathogenesis, gene, bone morphogenetic protein, osteopontin”. Consequently, 63 eligible literatures were included after the exclusion of the repetitive and old ones. RESULTS AND CONCLUSION:Current studies have shown that ossification of the ligamentum flavum is a disease that results from multiple genetic and environmental causes and is one of the main causes of spinal stenosis. Tissue degeneration, local biomechanics, genetic factors, metabolic disorders, trace elements and vascular inflammation are all shown to be involved in the pathogenesis of ossification of ligamentum flavum.
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Objective To investigate the pathogen distribution and risk factors of pulmonary infection after acute cervical spinal cord injury (ACSCI) in an attempt to offer reference for early antiinfection therapy.Methods The study comprised 223 cases who were admitted from October 2011 to October 2014.There were 149 males and 74 females,at (43.3 ± 13.5) years of age.Species of pathogens identified were gram-positive,gram-negative and mixed.Effects of age,gender,injury types and tracheotomy on pathogen distribution were analyzed.Results Gram-negative infection was found in 114 cases (51.1％),with tracheotomy accounting for 7.0％ of the cases and death accounting for 1.8％ of the cases,and the main causative pathogens were Klebsiella pneumonia,Escherichia coli,Pseudomonas aeruginosa and Acinetobacter baumannii.Gram-positive infection was found in 41 cases (18.4％),with tracheotomy accounting for 12.2％ of the cases and death accounting for 7.3％ of the cases,and the main causative pathogens were Staphylococcus aureus and Streptococcus pneumonia.Mixed infection was found in 68 cases (30.5％),with tracheotomy accounting for 22.1％ of the cases and death accounting for 13.2％ of the cases.Gender had no significant correlation with pathogen distribution.For the cases of complete spinal cord injury and tracheotomy,the ratio of mixed infection increased significantly (P ＜ 0.05).For the cases younger than 30 years,the pathogens were mainly gram-positive bacteria (P ＜ 0.05).Conclusions Main pathogens of pulmonary infection after ACSCI are gram-negative bacteria.The cases younger than 30 years are associated with higher risk of grampositive infection,while the cases with complete injury or tracheotomy are associated with higher risk of mixed infection.
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BACKGROUND:Exogenous basic fibroblast growth factor (bFGF) plays an important role in the ligament tissue healing process, and the use of transgenic methods to transfect exogenous genes into cells can promote the secretion of bFGF. OBJECTIVE:To observe phenotypic changes and the bFGF protein expression after bFGF recombinant adenovirus was used to transfect rabbit bone marrow mesenchymal stem cells (BMSCs). METHODS:Passage 2 BMSCs were divided into three groups:Ad.bFGF-eGFP group, Ad.eGFP group and control group. Under a phase contrast microscope we observed the changes in cellmorphology. The expression of bFGF protein in BMSCs was determined by enzyme-linked immunosorbent assay (ELISA). The proliferative curve was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). RESULTS AND CONCLUSION:The transfected cells showed a uniform phenotype of fibroblasts. MTT colorimetric assay revealed that more proliferative activity of transfected BMSCs was shown in the Ad.bFGF-eGFP group than in the Ad.eGFP group and control group. ELISA results showed that expression of bFGF protein was higher in the Ad.bFGF-eGFP group than in the Ad.eGFP group and control group (P<0.05). BFGF recombinant adenovirus can induce the differentiation of BMSCs into fibroblasts, increase proliferative ability and promote the expression of bFGF protein.
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BACKGROUND:Spinal cord ischemia-reperfusion injury is a serious secondary injury of the spinal cord. Multifactor could contribute to the mechanism of this injury, and many therapeutic measures emerge, but the therapeutic effect is not ideal. OBJECTIVE:To investigate the protective effects and mechanism of hydrogen-rich saline on spinal cord ischemia-reperfusion injury in rabbits. METHODS:ZIVIN method was adopted to prepare the model of spinal cord ischemia-reperfusion injury. The rabbit models were randomly divided into model group, sham operation group, and hydrogen-rich saline group. RESULTS AND CONCLUSION:Improved Tarlov scores for the evaluation of motor function were significantly increased in hydrogen-rich saline group compared with the model group at 6, 12, 24, 72 hours after reperfusion (P<0.01). The contents of malondialdehyde were significantly lower (P<0.05), while catalase activity was significantly higher (P<0.05) in hydrogen-rich saline group than that in model group at 72 hours after reperfusion. Hematoxylin-eosin staining revealed that, spinal cord anterior-horn motor neurons maintained intact structure in sham operation group;more necrotic spinal cord anterior-horn motor neurons were found in model group, and granular-vacuolar degeneration occurred in the endochylema. In hydrogen-rich saline group, the structure of spinal cord anterior-horn motor neurons was basical y intact, only a smal amount of spinal cord anterior-horn motor neurons appeared vacuolar degeneration. TUNEL staining showed no apoptotic spinal cord anterior-horn motor neurons in sham operation group. Many inflammatory cel s and apoptotic neurons were found in model group. There were few inflammatory cel s and apoptotic neurons in hydrogen-rich saline group. Hydrogen-rich saline can prevent the apoptosis of spinal cord anterior-horn motor neurons in rabbits with spinal cord ischemia-reperfusion injury, and the underlying mechanism is associated with antioxidative effect.
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BACKGROUND: Demineralized bone matrix and bone morphogenetic protein have been shown to have good bone induction, but less studies concerned nanometer demineralized bone matrix. Its physical and chemical properties and biological security are not yet clear. OBJECTIVE:On the basis of preparing the nanometer human demineralized bone matrix in previous experiment, we mixed the recombinant human bone morphogenetic protein-2 together to obtain the new bone graft substitute and to research its physical and chemical properties and biological security. METHODS:The human demineralized bone matrixes were prepared by the method of modified Urist and nano-processed then mixed with the bone morphogenetic protein-2 in specific proportions in order to be lyophilized to complete the fol owing experiments. (1) Pyrogen experiment:the material extracts were injected in the rabbits by ear intravenous. (2) Toxicity experiments:material extracts and saline were separately injected via the tail vein of mice in vivo. (3) Implantation experiments:experimental materials andβ-tricalcium phosphate were implanted into rabbits on both sides of the hindlimb muscle. RESULTS AND CONCLUSION:After lyophilized shaping, the nanometer demineralized bone matrix material had dense surface and it’s pore diameter was 100-400μm. The pore distribution was less uniform and the porosity was of less than 30%. The main elements were carbon, oxygen and nitrogen. Nanometer human demineralized bone matrix with recombinant human bone morphogenetic protein-2 did not have pyrogen effect and the rabbits’ body temperature had no significant fluctuations after injection. The acute systemic toxicity test results showed that the nanometer human demineralized bone matrix with recombinant human bone morphogenetic protein-2 complied with the relevant provisions of the State, without obvious toxic reaction. The inflammatory response of nanometer human demineralized bone matrix with recombinant human bone morphogenetic protein-2 was significantly lighter than the reaction ofβ-tricalcium phosphate. The results showed that the nanometer human demineralized bone matrix with recombinant human bone morphogenetic protein-2 is a nanometer al ogeneic bone graft substitutes with nontoxicity, good biocompatibility, high bioavailability, and less inflammatory reaction.
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Objective To investigate the role of Beclin 1 in the genesis and development of osteosarcoma and the effect of Beclin 1 overexpression on the growth of the in vitro osteosarcoma cell line MG63.Methods Real time-polymerase chain reaction (RT-PCR) and Western blot were used to detect the expressions of Beclin 1 in MG63 and hFOB1.19 at mRNA and protein levels ; A eukaryotic clone of plasmid pEGFP/Beclinl fusion with protein EGFP/Beclin 1 was constructed and was transfected into human osteosarcoma cell line MG63 by using lipofectamine 2000.The effect of Beclin1 overexpressions on the proliferation of MG63 cells was evaluated by MTT assay.Cell apoptosis was measured by flow cytomerty(FCM).Results The mRNA and protein expression of Beclin1 in human osteosarcoma cell line MG63 was significantly lower than that in the human osteoblast cell line hFOB1.19(0.17 ±0.06 vs 0.43 ±0.11,t =29.493,P ＜0.01 ; 0.13 ±0.05 vs.0.25 ± 0.08,t =6.325,P ＜ 0.01).The transfection of pEGFP/Beclinl increased the mRNA levels of human osteosarcoma(5.34 ± 0.50) times in transfected tumor cells MG63.The rate of cell apoptosis was low in control or transfected with lipofectamine 2000 only cells at an average of(0.10 ± 0.05) ％.The apoptosis rate was significantly higher in pEGFP/Beclin1 transfected cells than control cells ((4.3 ± 0.8) ％,t =5.752,P ＜ 0.05).Conclusion Compared with control cells,Bedin1 is down-regulated in the human osteosarcoma cell line MG63,which indicate the role of Beclin 1 in regulating the malignant behaviors of osteosarcoma.Beclin1 overexpressions inhibits cell proliferation and induces apoptosis in MG63 cells.
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Objective To analyze the incidence and possible etiological factors of hyponatremia after acute cervical spinal cord injury (CSCI),and evaluate the effect of severity of CSCI,age,sex and injured segment on hyponatremia.Methods From June 2005 to March 2011,a series of patients with CSCI caused by cervical vertebras trauma were treated in our department.Except patients combined with craniocerebral injury or chronic diseases,other patients were divided into three groups:complete CSCI group,incomplete CSCI group and no neurological disorder group.Concentration of natrium in blood in all patients was analyzed respectively.Results All 102 patients (83 males,19 females) were selected with an average of 45.6years old.There were 23 patients with complete CSCI,60 with incomplete CSCI and 19 with no neurological disorder.Hyponatremia was found in 15 patients in complete CSCI group,23 patients in incomplete CSCI group and 1 patient in no neurological disorder group.The incidence of hyponatremia was significantly different between three groups,among which the complete CSCI group had the highest incidence.Multiple linear regression analysis showed hyponatremia was obviously correlated with the injury degree of spinal cord,but not correlated with the age,sex and injury segment of the patients.Conclusion Hyponatremia is a common complication in patients suffered from CSCI.Although the balance of natrium in blood is very complicated and influenced by many factors,autonomic nerve system and neuroendocrine system dysfunction,and hemodynamic changes after CSCI may play a key role in happening of electrolytical abnormality.
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Objective To discuss the degenerative factors, the spinal segment distribution, and the mechanism in hyperextension injury of cervical spine. Method Eighty-nine patients with hyperextension injury of cervical spine were retrospectively analyzed by observing the degenerativelesion, the spinal cord segment with high signal in T2WI, and the location of facial trauma. Results Fifty-eight cases showed the disc hemiation which was the most common lesion, followed by 8 cases showing the calcification of the posterior longitudinal ligament. Besides, 7 cases presented the developmental stenosis of spinal canal, and also, 6 cases showed disc hemiation combined with the yellow ligament hypertrophy. The intervertebral level of the spinal cord with high signal in T2WI were distributed as follows:4 cases were at C2/3, of which onesuffered the forehead trauma; 12 cases were at C3/ 4, of which 10 had the forehead trauma, and one had the zygomatic trauma; 12 cases were at C4/5, of which 5 had the forehead trauma, one had both the zygomatic and the forehead trauma, and one had both the forehead and with the lower jaw trauma; 11 cases were at CS/6,of which 3 had the forehead trauma, 3 had the zygomatic trauma, and 2 had the lower jaw trauma. The location of the spinal cord with single high signal in T2WI did not correspond with the intervertebral disc level in 4 cases. For 10 cases the high signal in T2WI was found at two discontinuous segments. For 2 cases the 1 high signal in T2WI was found at over two segments. For 6 cases the high signal in T2WI was found at over three segments. Conclusions Disc hemiation is the most common underlyding factor in cervical hyperextension injury. The spinal level with high signal in T2WI was correlative to the impacted facial site. The shear force at the inflection point with or without the anterior-posterior compression force accounted for the cervical hyperextension injury.
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Objective To construct three-dimensional finite element model of lumbar spondylolysis,then to verify its validity by comparison of biomechanics in vitro.Method According to the radiological data of a patient with lumbar spondylolysis,the bone and intervertebral disc of L4-S1 were reconstructed by Simpleware software.The lumbar attaching ligaments and articular capsule were added into simulating model by Ansys software.The three-dimensional finite element model of lumbar spondylolysis was finally simulated successfully,and validated by lumbar spondylolysis biomechanical experiment in vitro.Results The reconstruction of digital model contained the bones of lumbar spine which include vertebral cortical bone,cancellous bone,facet joint,pedicle,lamina,transverse process and spinous process,as well as the annulus fibrosus,nucleus pulposus,superior and inferior end-plates.Besides,anterior and posterior longitudinal ligaments,flavum ligament,supraspinal and interspinal ligaments and articular capsule of facet joint are also attached.The model consisted of 281,261 nodes and 661,150 elements.Imitation of spondylolysis is well done in this model.The validity of the model was verified by comparison of the results of biomechanics in vitro which involved in the trends under loading of stress/strain of L4 inferior facet process,L5 superior and inferior facet process,S1 superior facet process and the trends of stress/strain of lateral and medial L4 inferior facet process.Conclusions Three-dimensional model of lumbar spondylolysis is reconstructed using finite element analysis,and can be further used in the research in biomechanics of lumbar spondylolysis.
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Objective To evaluate neurofunctional and radiographic results of transpedicular screw fixation reduction and anterior column fixation with use of screw-red system in treatment of multiple segment lumbar pedicle and vertebral body fractures combined with spondylolisthesis. Methods A consecutive series of 12 patients with unstable multiple segment lumbar pedicle fracture, vertebral body fracture, spondylolisthesis and neurologic deficit were managed with posterior transpedicular screw fixation including fractured pedicle and anterior screw-rod fixation instrumentation from January 2002 to December 2007. Results Patients were followed up for 24-30 months (mean 26 months). All the patients with incomplete neurologic deficits got improvement by at least one Frankel grade. Transpedicular screw brought satisfactory reduction. At the time of the latest follow-up, no screw breakage occurred. Con-clusions Excellent reduction of unstable multiple segment lumbar pedicle fractures combined with spon-dylolisthesis can attain better reduction and maintenance by means of selective pedicle screw fixation via fractured pedicle and anterior screw-rod instrument.
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Objective To evaluate retrospectively whether posterior longitudinal ligament(PLL)adhere to dura mater in the patients with cervical spondylotie myelopathy(CSM)or not before the anterior cervical operation.Methods From December 2005 to January 2007,of 18 patients with CSM the adhesion between PLL and dura mater was found in the anterior cervical operation.The patients included of 11 males and 7 females,with mean age of 65.4 years (range 55-72 years).All the patients were measured by CT and MRI before operation.There were 12 cases of dual-segmental cervical intervertebral disc herniation,6 of tri-segmental disc herniation.The former cases were treated with one level corpectomy and titanium mesh or iliac grafting and cervical anterior plate,and the latter with an additional cervical cage in the intervertebralspace.The floatation method was used to deal with the adhesion.The fitness between the two radiological methods was analyzed by matched-pairs Kappa eoemcient test.Results The nerve functions of all the patients were improved after anterior cervieal decompression.The mean score of JOA was increased from 9.6 of pre-operation to 12.1 of post-operation.There were 4 cases with injury in dura mater,which healed after appropriate dealing with the leakage of cerebrospinal fluid.None of lacerated dura was directly repaired during the operation.The condition of the coarse touch and bur between intervertebral disc and dura mater were found in CT transverse scanning.The thickening of the PLL and the unsymmetrical space between inferior and superior subdural cavity was found in MRI.The coefficient test proved that the difference of the CT and MRI was significant in finding the adhesion.Conclusion MRI iS better than CT in finding the adhesion between the PLL and dura mater in CSM before operation,besides the floatation method should be good to deal with the adhesion.
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Objective To investigate the effects of current major management strategies on early survival of patients with severe injury of cervical spinal cord. Methods A retrospective analysis was done on 532 patients with severe injury of cervical spinal cord (American Spinal Injury Association Grades A and B). The correlations of the early survival and major treatment measures, post-injury temporary immobilization of neck, operation, tracheotomy, systemic nutritional support, administration of glucocorticoid, were analyzed by Binary Logistic Regression. The problems related to the major treatment measures were also analyzed.Results 438 cases survived within 1 month. There was a positive correlation between the early survival and operation and nutritional support. There was a negative correlation between the early survival and tracheotomy.There was not any significant correlation between the early survival and the other 2 measures. The early sur-vival rate for patients of operation was 93.5%, for those without operation was 32. 7%, for those of goodnutrition was 97.8%, for those without good nutrition was 66. 7%, for those of tracheotomy was 58.1%, and for those without tracheotomy was 87.5%. Conclusions For patients with severe injury of cervical spinal cord, active operation and fine systemic nutritional support may increase early survival rate, undue tra-cheotomy may increase the risk of early death, and glucocorticoid may not have an effect on improvement of early survival rate.
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Objective To observe the changes of the peripheral blood T lymphocyte subsets following acute spinal cord injury and investigate the possible mechanism of these changes. Methods The SCI models of rats were made by Allen's method. Forty SD rats were divided into four groups, ie,normal control group, sham operation group, 100 g·cm group and 200 g·cm group. The expressions of CD4 and CD8 subsets of the peripheral blood T lymphocyte of the injured rats were determined by immunofluorescence labelling and flow cytometry at different times after injury. Results It was found that the expression of CD4 was significantly reduced to (30.40±4.76)% in 100 g·cm group and to (26.54± 9.34) % in 200 g·cm group, which were significantly lower than that of normal control group ( P ＜0.01 ). At 36 hours after injury, the ratio of CD4/CD8 was significantly reduced to 1.81 ± 0.55 in 100 g·cm group and and 1.29 ± 0.50 in 200 g·cm group, with statistical difference (P ＜ 0.05).Conclusions The immunoreaction is significantly depressed at the early stage of acute spinal cord injury. The severer injury results in more significant decrease of CD4 and ratio of CD4/CD8. The changes of CD4 and CD4/CD8 ratio can be used to indicate the severity of spinal cord injury.