Integrated miRNA-mRNA network revealing the key molecular characteristics of ossification of the posterior longitudinal ligament.

BACKGROUND: Ossification of the posterior longitudinal ligament (OPLL) refers to an ectopic ossification disease originating from the posterior longitudinal ligament of the spine. Pressing on the spinal cord or nerve roots can cause limb sensory and motor disorders, significantly reducing the patient's quality of life. At present, the pathogenesis of OPLL is still unclear. The purpose of this study is to integrate microRNA (miRNA)-mRNA biological information data to further analyze the important molecules in the pathogenesis of OPLL, so as to provide targets for future OPLL molecular therapy. METHODS: miRNA and mRNA expression profiles of GSE69787 were downloaded from Gene Expression Omnibus database and analyzed by edge R package. Funrich software was used to predict the target genes and transcription factors of de-miRNA. Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis of differentially expressed genes (DEGs) were carried out based on CLUEGO plug-in in Cytoscape. Using data collected from a search tool for the retrieval of interacting genes online database, a protein-protein interaction (PPI) network was constructed using Cytoscape. The hub gene selection and module analysis of PPI network were carried out by cytoHubba and molecular complex detection, plug-ins of Cytoscape software respectively. RESULTS: A total of 346 genes, including 247 up-regulated genes and 99 down-regulated genes were selected as DEGs. SP1 was identified as an upstream transcription factor of de-miRNAs. Notably, gene ontology enrichment analysis shows that up- and down-regulated DEGs are mainly involved in BP, such as skeletal structure morphogenesis, skeletal system development, and animal organ morphogenesis. Kyoto Encyclopedia of Genes and Genomes enrichment analysis indicated that only WNT signaling pathway was associated with osteogenic differentiation. Lymphoid enhancer binding factor 1 and wingless-type MMTV integration site family member 2 Wingless-Type MMTV Integration site family member 2 were identified as hub genes, miR-520d-3p, miR-4782-3p, miR-6766-3p, and miR-199b-5p were identified as key miRNAs. In addition, 2 important network modules were obtained from PPI network. CONCLUSIONS: In this study, we established a potential miRNA-mRNA regulatory network associated with OPLL, revealing the key molecular mechanism of OPLL and providing targets for future treatment or prevent its occurrence.

Patient Satisfaction with Posterior Decompression Surgery for Cervical Ossification of the Posterior Longitudinal Ligament: Prognostic Radiographic Factors and Patient-Reported Outcomes for the Effectiveness of Surgical Treatment.

OBJECTIVE: To identify the prognostic factors associated with patient satisfaction after double-door laminoplasty for cervical compression myelopathy due to ossification of the posterior longitudinal ligament (OPLL). METHODS: The study group comprised 44 patients (30 males and 14 females) with OPLL who underwent double-door laminoplasty at our institution with a minimum follow-up of 1 year. The mean patient age was 63.8 years (range, 48-86 years). We evaluated the patients' postoperative satisfaction using a questionnaire and divided them into 2 groups, satisfied and dissatisfied. We assessed various radiographic parameters. The patient-reported outcomes, including the Short Form-36 Physical Component Summary (SF-36 PCS), Neck Disability Index, neck pain, arm pain, and Japanese Orthopedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), were assessed and used to evaluate the effectiveness of surgical treatment according to the concept of minimum clinically important difference (MCID). RESULTS: The satisfied group comprised 29 patients (65.9%). The dissatisfied group had a higher percentage of hill-shaped ossifications compared with the satisfied group (46.7% vs 17.2%; P = 0.04). The satisfied group had a higher proportion of patients with SF-36 PCS reaching the MCID threshold value (81.8% vs 14.3%; P < 0.01) and with effective surgical treatment as evaluated by the JOACMEQ lower extremity function domain (61.5% vs 10.0%; P < 0.01). CONCLUSION: Patient satisfaction after laminoplasty was insufficient in patients with a hill-shaped ossification. The patients with OPLL who were able to recognize a difference in their clinical physical function, especially lower extremity function, were satisfied after laminoplasty.

[Updates on ossification of posterior longitudinal ligament. Quality of life (QOL) of patients with OPLL].

Among the research conducted under the Health Labour Sciences Research Grant Program by the study group on ossification of spinal ligaments, we reviewed studies on patients with ossification of the posterior longitudinal ligament (OPLL) with regard to methods for assessing their QOL as well as the study results. Methods for assessing QOL included the use of a single question, health-related QOL scales such as the SF-36 and SF-8, and the QOL criteria used in the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) . In patients with OPLL, which is a condition characterized by pain and numbness that primarily affects the patient's lifestyle rather than survival, the degree of pain was strongly related to QOL. Among activities of daily living, transferring and bathing were strongly related to QOL. Therefore, it is important to maintain appropriate rehabilitation.

Quality of life in elderly patients with ossification of the posterior longitudinal ligament.

STUDY DESIGN: A longitudinal cohort study of 216 elderly patients with ossification of the posterior longitudinal ligament for an average of 13 years was performed. OBJECTIVE: To know the quality of life experienced by patients after treatment. SUMMARY OF BACKGROUND DATA: No report is available on the quality of life experienced by elderly patients with ossification of the posterior longitudinal ligament. Because the life prognosis of patients with this condition is relatively good, the quality of life experienced by elderly patients with this disease is an important subject. METHODS: The study participants were 216 elderly patients with ossification of the posterior longitudinal ligament. Conservative therapy was performed for 126 patients, and surgical therapy for 90 patients. Surgery was basically indicated for patients with myelopathy, who were classified using Nurick's grading system. The cumulative survival rate of these patients and their disabilities in daily living were reviewed. The occurrence of fracture resulting from osteoporosis was surveyed, and the relation of such fractures to bone mineral density was examined. RESULTS: The cumulative survival rate of 70-year-old patients exhibiting Nurick Grade 5 severe myelopathy before treatment was 20%, whereas that of patients without myelopathy or those with Grades 1, 2, 3, or 4 myelopathy before treatment was 80%. Patients who underwent surgical therapy for Grade 3 or 4 myelopathy were statistically more likely to be independent of assistance with activities of daily living than those with similar degrees of myelopathy who underwent conservative therapy. The final quality of life was poor for patients with Grade 5 myelopathy at the first examination, regardless of therapeutic method. The prevalence of complication by fracture in patients with ossification of the posterior longitudinal ligament was 1.4% for men and 8.6% for women. The bone mineral density in these patients without myelopathy was significantly higher than in healthy subjects of the same age. CONCLUSION: The study data suggest that surgical treatment should be chosen for patients exhibiting moderate myelopathy to obtain satisfactory quality of life for them over a long period.