ObjectiveTo investigate the short-term effectiveness of ISOBAR TTL semi-rigid dynamic stabilization system (ISOBAR TTL system) in treatment of lumbar degenerative disease. MethodsBetween June 2007 and May 2011, 38 cases of lumbar degenerative disease were treated, including 24 males and 14 females with an average age of 51.2 years (range, 21-67 years). The disease duration was 8 months to 10 years (mean, 4.7 years). In 38 cases, there were 4 cases of grade I spondylolisthesis, 11 cases of lumbar instability and lumbar disc protrusion, 21 cases of lumbar spinal stenosis and lumbar disc protrusion, and 2 cases of postoperative recurrence of lumbar disc protrusion. There were 22 cases of adjacent segment disc degeneration. All cases underwent posterior decompression and implantation of ISOBAR TTL system. The double-segment-fixed patients underwent interbody fusion. Visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) scores for low back pain were used to evaluate clinical outcomes. The range of motion (ROM) at the semi-rigid dynamic stabilization segment was also measured. ResultsThe other cases achieved healing of incision by first intention, except 1 case of delayed healing. All the patients were followed up 8-53 months (mean, 27.8 months). After operation, ISOBAR TTL system showed reliable fixation, and no loosening, breakage, or kyphosis deformity occurred. No adjacent segment degeneration was observed. The ROM of the fixed segments was 0-1° in 3 cases, 1-2° in 4 cases, 2-3° in 14 cases, 3-4° in 15 cases, and gt; 4° in 2 cases. At last follow-up, the VAS score was 1.93 ± 2.43, and was significantly lower than preoperative score (8.20 ± 1.78) (t=7.761, P=0.000). JOA score was 23.06 ± 7.75, and was significantly higher than preoperative score (4.87 ± 3.44) (t=10.045, P=0.000). According to Stauffer-Coventry evaluation standard, the results were excellent in 32 cases, good in 3 cases, fair in 2 cases, and poor in 1 case, with an excellent and good rate of 92.1%. ConclusionGood short-term effectiveness can be achieved by surgical intervention with ISOBAR TTL system in treatment of lumbar degenerative disease.
Objective To establ ish sophisticated three-dimensional finite element model of the lower cervical spine and reconstruct lower cervical model by different fixation systems after three-column injury, and to research the stress distribution of the internal fixation reconstructed by different techniques. Methods The CT scan deta were obtained from a 27-year-old normal male volunteer. Mimics 10.01, Geomagic Studio10.0, HyperMesh10.0, and Abaqus 6.9.1 softwares were usedto obtain the intact model (C3-7), the model after three-column injury, and the models of reconstructing the lower cervical spine after three-column injury through different fixation systems, namely lateral mass screw fixation (LSF) and transarticular screw fixation (TSF). The skull load of 75 N and torsion preload of 1.0 N•m were simulated on the surface of C3. Under conditions of flexion, extension, lateral bending, and rotation, the Von Mises stress distribution regularity of internal fixation system was evaluated. Results The intact model of C3-7 was successfully establ ished, which consisted of 177 944 elements and 35 668 nodes. The results of the biomechanic study agreed well with the available cadaveric experimental data, suggesting that they were accord with normal human body parameters and could be used in the experimental research. The finite element models of the lower cervical spine reconstruction after three-column injury were establ ished. The stress concentrated on the connection between rod and screw in LSF and on the middle part of screw in TSF. The peak values of Von Mises stress in TSF were higher than those in LSF under all conditions. Conclusion For the reconstruction of lower cervical spine, TSF has higher risk of screw breakage than LSF.
Objective To investigate the mechanism of p38 mitogen activated protein kinase (MAPK) signaling pathway in regulating the hyperplasia and hypertrophy of human lumbar ligamentum flavum via transforming growth factor β1 (TGF-β1)/connective tissue growth factor (CTGF). Methods The lumbar ligamentum flavum tissue taken from patient with lumbar intervertebral disc herniation was isolated by collagenase-predigested explant cultures. The ligamentum flavum cells were treated with the extracellular regulated protein kinase pathway blocker PD98059, c-Jun N-terminal kinase pathway blocker SP600125, and p38 pathway blocker SB203580, and then the mRNA expressions of CTGF, collagen type Ⅰ, and collagen type Ⅲ were detected by real-time fluorescence quantitative PCR (qRT-PCR). The ligamentum flavum cells were divided into 4 groups, and transfected with small interfering RNA (siRNA), p38 siRNA, siRNA+3 ng/mL TGF-β1, and p38 siRNA+3 ng/mL TGF-β1 in groups A, B, C, and D, respectively. After 24 hours of transfection, immunofluorescence staining was performed to observe the expressions of p38 and phosphorylation p38 (p-p38); the relative mRNA expressions of CTGF, collagen type Ⅰ, and collagen type Ⅲ in each group were detected by qRT-PCR; the protein expression of CTGF in each group was detected by Western blot. Results p38 pathway blocker SB203580 could significantly reduce the relative mRNA expressions of CTGF, collagen type Ⅰ, and collagen type Ⅲ (P<0.05). After 24 hours of transfection, immunofluorescence staining showed positive staining with p38 and p-p38 expressions in groups A, C, and D and negative staining in group B. Compared with group A, the relative mRNA expressions of CTGF, collagen type Ⅰ, and collagen type Ⅲ and relative protein expression of CTGF in group B decreased significantly (P<0.05), while those in groups C and D increased significantly (P<0.05); and those indicators significantly increased in group C than in group D (P<0.05). Conclusion TGF-β1/CTGF based on the p38 MAPK signaling pathway play an important role in the occurance and development of hypertrophy of human lumbar ligamentum flavum.
ObjectiveTo investigate the effect of transforming growth factor β1 (TGF-β1) induced proliferation of ligamentum flavum cells and ligamentum flavum hypertrophy and its effect on connective tissue growth factor (CTGF) expression.MethodsThe ligamentum flavum tissue in lumbar intervertebral disc herniation was extracted and the ligamentum flavum cells were isolated and cultured by collagenase pre-digestion method. Morphological observation, immunofluorescence staining observation, and MTT assay were used for cell identification. The 3rd generation ligamentum flavum cells were divided into 5 groups. The cells of groups A, B, C, and D were respectively sealed with 3 ng/mL TGF-β1, 50 ng/mL CTGF, 3 ng/mL TGF-β1+CTGF neutralizing antibody, and 50 ng/mL CTGF+CTGF neutralizing antibody. Serum free DMEM was added to group E as the control. MTT assay was used to detect the effects of TGF-β1 and CTGF on the proliferation of ligamentum flavum cells. Western blot was used to detect the expression of CTGF protein. Real-time fluorescence quantitative PCR (qRT-PCR) was used to detect the expression of collagen type Ⅰ, collagen type Ⅲ, and CTGF genes.ResultsThe morphological diversity of cultured ligamentum flavum cells showed typical phenotype of ligamentum flavum fibroblasts; all cells expressed collagen type Ⅰ and vimentin, and some cells expressed collagen type Ⅲ; MTT identification showed that with the prolongation of culture time, the absorbance (A) value of each generation of cells increased gradually, and the A value of the same generation of cells at each time point was significantly different (P<0.05), there was no significant difference in A value between the cells of each generation at the same time point (P>0.05). After cultured for 24 hours, MTT assay showed that the A value of cells in groups A and B was significantly higher than that of group E (P<0.05). After adding CTGF neutralizing antibody, the A value of cells in groups C and D decreased, but it was still higher than that of group E (P<0.05). There were also significant differences among groups A, C and groups B, D (P<0.05). Western blot analysis showed that the relative expression of CTGF protein in groups A and B was significantly higher than that in group E (P<0.05), while the relative expression of CTGF protein in groups C and D was significantly lower than that in group E (P<0.05), and the difference between groups A, C and groups B, D was also significant (P<0.05). qRT-PCR detection showed that the mRNA relative expression of CTGF, collagen type Ⅰ, and collagen type Ⅲ in group A was significantly higher than that in group E (P<0.05). After adding neutralizing antibody, the mRNA relative expression of genes in group C was inhibited and were significantly lower than that in group A, but still significantly higher than that in group E (P<0.05). The mRNA relative expressions of collagen type Ⅰ and collagen type Ⅲ in group B was significantly higher than that in group E (P<0.05), but the mRNA relative expression of CTGF was not significantly different from that in group E (P>0.05); after neutralizing antibody was added, the mRNA relative expression of collagen type Ⅰ and collagen type Ⅲ in group D was inhibited and was significantly lower than that in group B, but still significantly higher than that in group E (P<0.05); there was no significant difference in the mRNA relative expression of CTGF between group D and groups B, E (P>0.05).ConclusionTGF-β1 can promote CTGF, collagen typeⅠ, collagen type Ⅲ gene level and protein expression in ligamentum flavum cells, and TGF-β1 can synergistically promote proliferation of ligamentum flavum cells through CTGF.