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Objective To investigate the correlation between vital capacity, pulmonary ventilation and morphological parameters among children living in different altitude areas, so as to provide a reference basis for the development of prevention and control strategies for high altitude illness. Methods From January 2019 to June 2020, primary and secondary school students aged 7 to 15 years old were randomly selected from three different altitude areas, which were Xining (2 260m, low altitude group), Haixi (2 900m, medium altitude group), and Yushu (4 493m, high altitude group), respectively. The vital capacity, pulmonary ventilation and morphological parameters of the selected children were recorded. Results The vital capacity, pulmonary ventilation and morphological parameters showed statistically significant difference among three groups (P<0.05). The vital capacity and pulmonary ventilation were positively correlated with lung volume, but negatively correlated with lung density and lung artery diameter (P<0.05). Logistic regression analysis showed that there were three factors affecting children's vital capacity and lung ventilation: mean lung density, total lung transverse diameter, and total lung volume (P<0.05). Conclusion The monitoring of lung morphological indexes, mean lung density, total lung transverse diameter, and total lung volume can effectively judge children's lung function, and have certain value in the prevention and treatment of related high-altitude illness.
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Objective:To explore the value of the Pfirrmann grading standard for disc degeneration in the quantification of heterotopic ossification (HO) after artificial cervical disc replacement (ACDR).Methods:Data of 120 patients who underwent ACDR from January 2009 to December 2016 were retrospectively analyzed. There were 88 males and 32 females with an average age of 43.86±8.69 (range, 27-67) years old. There were 100 single-level replacements (9 Hybrid cases) and 20 double-level replacements (3 Hybrid cases). The occurrence of HO was observed by lateral radiographs of the cervical spine. The HO severity was assessed using the McAfee rating system. Degeneration degrees of cervical intervertebral discs were evaluated by the Pfirrmann grading standard based on the preoperative cervical MRI. The weighted Kappa test was used to analyze the consistency of evaluations between different observers of the Pfirrmann scoring system and the McAfee grading system. Pfirrmann scores for preoperative disc degeneration in the HO and non-HO groups were compared using the t-test. The chi-square test was used to analyze the effect of the Pfirrmann score on the incidence of postoperative segmental HO. The correlation between Pfirrmann score and McAfee grade, as well as postoperative ROM of HO group were analyzed by the Spearman rank-sum test. Quantitative indicators for risks of HO after ACDR surgery were proposed based on the incidence of segment HO in different Pfirrmann score groups. Results:One hundred and twenty patients were followed up for an average of 74.08±28.05 (range, 31-125) months. Based on statistics of cases 2 years after surgery, the overall HO incidence was 31.67% (38/120). The HO incidence was 27% (27/100) and 55% (11/20) for single-level and double-level replacements, respectively. There were 46 replacement segments in the HO group and 94 replacement segments in the non-HO group. The Pfirrmann score of HO group (3.17±1.08) was 25.80% significantly higher than that of the non-HO group (2.52±0.98) ( t=3.46, P=0.01). The incidence of HO in the replacement segment increased significantly with the preoperative Pfirrmann score ( χ2=12.44, P=0.01). The Pfirrmann score of the intervertebral disc in the HO group had a significant positive correlation with the McAfee grade ( R=0.54, P=0.01) and a significant negative correlation with the ROM ( R=-0.75, P=0.01). At 2 years after the operation, when the Pfirrmann score of the intervertebral disc was less than 3, the incidence of HO in the replacement segment was 20.55%(15/73); when the Pfirrmann score was equal to 3, the incidence of HO was 38.46% (10/26); when the Pfirrmann score was greater than 3, HO incidence was 51.22% (21/41). Conclusion:The Pfirrmann score of cervical disc degeneration was significantly related to the incidence of HO, McAfee grade, and ROM in the postoperative replacement segment. The Pfirrmann score of cervical disc degeneration can be used as a quantitativeindicator of HO risk in ACDR.
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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:The pathogenesis of ligamentum flavum hypertrophy remains poorly understood, and the expression of transforming growth factor beta1 (TGF-β1) is increased notably. Reactive oxygen species (ROS) accumulation is associated with tissue degeneration, which may accelerate the progression of ligamentum flavum hypertrophy by upregulating TGF-β1 expression. OBJECTIVE:To clarify the effect and significance of ROS H2O2-mediated up-regulation of TGF-β1 and collagen type Ⅰ in the progress of ligamentum flavum hypertrophy. METHODS:Ligamentum flavum was removed from a case of acquired lumbar disc herniation with normal ligamentum flavum during lumbar posterior decompression surgery, and then separated and cultured in vitro to the 4-6 generations, followed by exposure to H2O2 at various concentrations (0, 50, 100, 150, 200μmol/L) for 72 hours. The mRNA and protein expression levels of TGF-β1 and collagen type Ⅰ were detected by real-time PCR and western blot assay, respectively. RESULTS AND CONCLUSION:Real-time quantitative PCR showed that the mRNA expression level of TGF-β1 was significantly increased in the 150 and 200μmol/L groups (P<0.05). The mRNA expression level of collagen type Ⅰ was significantly higher in the experimental groups than that in the control group, especially in the 200μmol/L group (P<0.05). Western blot assay revealed that the protein expression levels of TGF-β1 and collagen type Ⅰ were significantly increased in a dose-dependent manner (P<0.05). These findings indicate that H2O2 may accelerate the progression of ligamentum flavum hypertrophy by up-regulating the expression levels of TGF-β1 and collagen type Ⅰ.
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BACKGROUND:The exact pathogenesis of ossification of ligamentum flavum has not been elucidated yet. And osteopontin may be an important factor involved in the ossification of ligamentum flavum. OBJECTIVE:To clarify the expression and significance of osteopontin and its receptors, CD44 and integrin-β3, in ligamentum flavum cels between normal controls and patients with ossification of ligamentum flavum.METHODS:Ligamentum flavum tissues were obtained from normal adult controls and adult patients with ossification of ligamentum flavum (n=8 per group) who underwent thoracic/lumbar posterior decompression surgery. Ligmentum flavum cels were separated, cultured and identifiedin vitro, and osteopontin, CD44, integrin-β3 were stained using immunocytochemistry method and observed under inverted phase contrast microscope. And the mRNA expressions of osteopontin, CD44, integrin-β3 were measured by RT-PCR. RESULTS AND CONCLUSION: Immunocytochemistry results showed that the stronger positive staining for osteopontin, CD44, integrin-β3 was observed in the ossification of ligamentum flavum group than the control group (P < 0.01). The mRNA expressions of osteopontin, CD44 and integrin-β3 were also higher in the ossification of ligamentum flavum group than the control group (P < 0.05). These findings indicate that osteopontin and its receptors, CD44 and integrin-β3, in ligamentum flavum cels may play an important role in ossification of ligamentum flavum.
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BACKGROUND:Current decelularized methods have the certain damage to the extracelular matrix and reduce the biomechanical properties of acelular scaffolds. OBJECTIVE:To explore the biomechanical properties of decelularized scaffold of lyophilized bovine tendon. METHODS:Sixty lyophilized fiber bundles from fresh flexion tendon of calf toes were randomly divided into two groups: control group and experimental group. In the experimental group, serine protease inhibitors were placed asepticaly for 24 hours at room temperature, then the samples were rinsed with PBS and transferred to the low concentration of trypsin+ethanol mixed solution to remove the cel wal without destruction of the extracelular matrix at room temperature for 5 hours; after that, the fiber bundles were cultured in DNA enzyme solution for 5 hours, finaly the acelular scaffold was completed and rinsed with PBS for 48 hours and dried at room temperature in sterile room. No treatment was done in the control group. Modulus of elasticity, durability and maximum stress were determined in the two groups. RESULTS AND CONCLUSION:Similar elastic modulus and durability were found in the two groups, but the maximum stress in the experimental group was significantly lower than that in the control group (P < 0.01). These findings indicate that the lyophilized acelular tendon fibers can mimic the biological function of bovine tendon fibers to a certain extent.
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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.