Etiology for Degenerative Disc Disease

Degenerative disc disease is a multifaceted progressive irreversible condition and an inevitable part of aging,which has been found to be a contributing factor for low back pain and might cause radiculopathy,myelopathy,spinal stenosis,degenerative spondylolisthesis,and herniations.Its etiology is complex and multifactorial.Although genetics influence more dominant,the occupational and mechanical influences still persist as a major risk factor.This review emphasizes up-to-date knowledge regarding etiology of disc degeneration with special consideration on occupational,lifestyle factors,and genetic polymorphisms.

Magnetic resonance imaging-based interpretation of degenerative changes in the lower lumbar segments and therapeutic consequences

Intervertebral disc degeneration and facet joint osteoarthritis of the lumbar spine are, among others, wellknown as a cause of low back and lower extremity pain. Together with their secondary disorders they set a big burden on health care systems and economics worldwide. Despite modern imaging modalities, such as magnetic resonance imaging, for a large proportion of patients with low back pain(LBP) it remains difficult to provide a specific diagnosis. The fact that nearly all the lumbar structures are possible sources of LBP, may serve as a possible explanation. Furthermore, our clinical experience confirms, that imaging alone is not a sufficient approach explaining LBP. Here, the Oswestry Disability Index, as the most commonly used measure to quantify disability for LBP, may serve as an easy-toapply questionnaire to evaluate the patient's ability to cope with everyday life. For therapeutic purposes, among the different options, the lumbar facet joint intraarticular injection of corticosteroids in combination with an anaesthetic solution is one of the most frequently performed interventional procedures. Although widely used the clinical benefit of intra-articular steroid injections remains controversial. Therefore, prior to therapy, standardized diagnostic algorithms for an accurate assessment, classification and correlation of degenerative changes of the lumbar spine are needed.

Association Between VDR FokI Polymorphism and Intervertebral Disk Degeneration

Intervertebral disk degeneration （IDD） is strongly associated with genetic predisposition and environmental susceptibility. Several studies been conducted to investigate the potential asso- ciation between IDD and FokI polymorphism located in the gene encoding the vitamin D receptor （VDR）, and inconsistent conclusions had been reached among different ethnic populations. In order to assess the association between the FokI polymorphism and the risk of IDD, we performed a comprehensive and systematic meta-analysis. Candidate articles were retrieved from PubMed, EMBASE, China National Knowledge Infrastructure （CNKI）, and China Biology Medical （CBM） with strict inclusion criteria in January 2015. Among the 54 articles that were retrieved, only eight studies met the inclusion criteria. The pooled data analysis based on allele contrast, homozy- gore, heterozygote, dominant, and recessive models revealed no significant correlation between the FokI polymorphism and the risk of IDD. However, when stratified by ethnicity, significant associ- ations were detected for Hispanics based on allele contrast （OR = 1.395, 95% CI = 1.059-1.836, P = 0.018）, homozygote （OR = 1.849, 95% CI = 1.001-3.416, P = 0.049）, heterozygote （OR = 1.254, 95% CI = 1.049-1.498, P = 0.013）, and dominant （OR = 1.742, 95% CI = 1.174-2.583, P = 0.006） models, and for Asians using the dominant model （OR = 1.293, 95% CI = 1.025-1.632, P --- 0.030）, whereas there is no significant association detected for Caucasians. In conclusion, FokI polymorpbism is not generally associated with IDD, but there is increased risk for IDD in Hispanics and Asians carrying FokI allele T.