The epidural venous plexus is considered as a cause of low back and leg pain but has been neglected for a long time. As an auxiliary drainage system of the vena cava, the epidural venous plexus plays an important role in the circulation of body fluids, and its tortuous expansion may lead to clinical symptoms similar to a herniated disc or spinal stenosis, by compressing nerve roots or dura. Due to the lack of specificity of imaging findings, it is difficult to distinguish accurately from disc herniation or spinal stenosis. The epidural venous plexus is tortuous and thin-walled, which is easy to be broken during the operation that resulted in obscuring the surgical field and leading to other complications such as postoperative hematoma. Despite researches of epidural venous plexus have been carried out for years, details are still left unknow. We hereby reviewed the latest research progress of the epidural venous plexus including anatomical structure, morphological characteristics, clinical significance and imaging examination.

Circular RNA (circRNA) is a kind of RNA with a circular structure. The unique structure of circRNA endows it with various cell biological functions and characteristics. It has become a research hotspot recently. CircRNA can play a role via mechanisms, such as microRNA (miRNA) sponge, RNA binding protein, peptide translation and regulation of gene transcription. CircRNA was found to be associated with disc degeneration, spinal cord injury, scoliosis, and facet arthritis. Some techniques, including bioinformatics and molecular biology techniques, microarray and high-throughput sequencing, can be used to predict and to discover disease-related circRNA, aiming to evaluate whether circRNA can be used as a molecular biomarker for spinal and spinal cord diseases. Based on the current role of circRNA, the corresponding therapeutic strategies have been carried out in experimental animals, which can provide theoretical basis for gene therapy. At present, the researches in circRNA for spinal and spinal cord diseases are still insufficient compared with those in other fields. Currently, the main direction focuses on the miRNA sponge mechanism of circRNA. Due to the variety of diseases in spinal surgery, the research progress of circRNA is also varied. In addition, the development of microarray and high-throughput sequencing technology have greatly promoted the researches in circRNA. The availability of public database is of great significance in the study. The present review summarized the current researches status of circRNA in spinal and spinal cord diseases, aiming to deepen understanding of circRNA in spinal and spinal cord diseases.