Objective To summarize the characteristic imaging signs of ossification of the ligamentum flavum (OLF) associated with dural adhesions by analyzing retrospectively the imaging signs of OLF associated with dural adhesions. Methods A retrospective analysis was made on clinical data of 85 patients undergoing OLF surgery between January 2010 and September 2012. The patients were assigned into the study group and the control group according to the preoperative imaging signs. Of 85 patients, 34 had both “tram track sign” and “jagged line sign” as the study group and 51 had either “tram track sign” or “jagged line sign” and neither of them as the control group. Adherence between dura mater and ligamentum flavum was observed during operation as the “gold standard” for the diagnosis of dural adhesion. The imaging information of CT and MRI in sagittal and axial planes was analyzed. The typical characteristics of dural adhesions were found. Then the sensitivity, specificity, and positive likelihood ratio of the preoperative imaging examinations were calculated to estimate the reference value and diagnostic value (gt; 5 having reference value, and gt; 10 having diagnostic value). Results In the study group, dural adhesion was observed in 26 patients (10 males and 16 females), and the other 8 patients (6 males and 2 females) had no dural adhesion. In the control group, dural adhesion was found in 2 female patients who had “jagged line sign”, and 49 patients had no dural adhesion (14 males and 35 females). In patients having both “tram track sign” and “jagged line sign”, the sensitivity was 92.9%; the specificity was 86.0%; and the positive likelihood ratio was 6.6. In patients having “tram track sign”, the sensitivity was 92.9%; the specificity was 64.9%; and the positive likelihood ratio was 2.6. In patients having “jagged line sign”, the sensitivity was 100%; the specificity was 77.2%; and the positive likelihood ratio was 4.4. Conclusion For patients with OLF having both “tram track sign” and “jagged line sign”, preoperative CT and MRI have a reference value for diagnoses of the OLF associated with dural adhesions.
Objective To investigate the surgery tactics for ossification of ligamentum flavum (OLF) associated with dural ossification (DO) in the thoracic spine and the cl inical outcome. Methods Between June 2006 and December 2009, 98 patients with thoracic spinal stenosis secondary to OLF were treated, and DO was found in 18 cases during operation. There were 11 males and 7 females with a mean age of 58 years (range, 46-73 years). The disease duration ranged from 5 to 48 months (mean,20 months). All patients underwent surgical decompression because of recent neurological aggravation. Both DO and OLF were resected with octagonal decompression by dissecting pedicle flavum tunnel. The Japanese Orthopaedic Association (JOA) score, modified Oswestry Disabil ity Index (ODI), and the Cobb angle were used to evaluate the effectiveness. Results The initial symptoms were significantly alleviated postoperatively. All patients had transient cerebrospinal fluid (CSF) leakage postoperatively, the CSF leakage disappeared after 8-10 days of conservative treatment. All the incisions healed by first intention. There was no complication of neurologic function deterioration, meningitis, wound infection, or spinocutaneous fistula. Eighteen patients were followed up 20-60 months (mean, 49 months). No recurrence of spinal cord compression symptoms,or neurologic function deterioration was observed at last follow-up. The JOA scores and effectiveness and modified ODI scores were significantly improved after 1 month and 12 months of operation when compared with preoperative scores (P lt; 0.05). The Cobb angles of kyphosis of the involved vertebrae were (6.7 ± 1.6)° before operation and (8.0 ± 1.2)° after 12 months of operation, showing significant difference (t=4.000，P=0.001). Postoperative T2-weighted axial MRI, sagittal MRI scan, and short T1 inversion recovery MRI showed that compressed deformity of the spinal cord returned to normal. Conclusion The surgery tactics for thoracic spinal stenosis secondary to the OLF with DO is safe, and no patching dura mater tears is effective.
OBJECTIVE: To provide a better treatment method of lumbar stenosis and root pain resulting from simple hypertrophy of ligamentum flavum. METHODS: By studying the records of 143 lumbar pain cases, we found 5 cases caused by simple hypertrophy of ligamentum flavum. All the patients were old man with a long progressed history. There was little difference of clinical features between the disc herniation and hypertrophy of ligamentum flavum. All cases accepted resection of ligamentum flavum. RESULTS: All the symptoms were relieved postoperatively. The patients could walk. CONCLUSION: The degeneration of lumbar ligamentum flavum can cause lumbar stenosis and root pain. Resection of ligamentum flavum can relieve the symptom.
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.
Objective To investigate the safety and effectiveness of unilateral biportal endoscopy (UBE) technique in the treatment of single-segment thoracic ossification of ligamentum flavum (TOLF). Methods Between August 2020 and December 2021, 11 patients with single-segment TOLF were treated with UBE technique. There were 6 males and 5 females, with an average of 58.2 years (range, 49-72 years). The responsible segment was T6, 7 in 1 case, T7, 8 in 1 case, T8, 9 in 2 cases, T9, 10 in 2 cases, T10, 11 in 2 cases, and T11, 12 in 3 cases. Imaging examination showed that the ossification were located on the left side in 4 cases, on the right side in 3 cases, and on bilateral sides in 4 cases. The main clinical symptoms were chest and back pain or lower limb pain, all accompanied by lower limb numbness and fatigue. The disease duration ranged from 2 to 28 months (median, 17 months). The operation time, postoperative hospital stay, and complications were recorded. Visual analogue scale (VAS) score was used to evaluate the chest and back pain and low limb pain, and Oswestry disability index (ODI) and Japanese Orthopedic Association (JOA) score were used to evaluate functional recovery before operation and at 3 days, 1 month, 3 months after operation, and last follow-up. The anteroposterior diameter of the coronal spinal canal was measured by CT before and after operation to evaluate the effect of surgical decompression. Results All operations were successfully completed. The operation time was 50-105 minutes, with an average of 80.0 minutes. No postoperative complication such as dural sac tear, cerebrospinal fluid leakage, spinal nerve injury, or infection occurred. The postoperative hospital stay was 2-5 days, with an average of 3.1 days. All incisions healed by first intention. All patients were followed up 6-22 months, with an average of 14.8 months. CT measurement at 3 days after operation showed that the anteroposterior diameter of the spinal canal was (8.63±1.61) mm, which was significantly larger than that before operation [(3.67±1.37) mm] (t=−12.181, P<0.001). The VAS score of chest and back pain and lower limb pain and ODI at each time point after operation were significantly lower than those before operation (P<0.05). The above indexes were further improved after operation, except that there was no significant difference between at 3 months after operation and at last follow-up (P>0.05), the differences between other time points were significant (P<0.05). There was no recurrence during the follow-up period. Conclusion UBE technique is a safe and effective method to treat single-segment TOLF, but its long-term effectiveness needs to be further studied.