ABSTRACT
The important function of the endplate is to transmit stress and supply nutrition. Endplate degeneration might induce or promote degeneration of the intervertebral disc, causing a series of spine diseases that seriously impair people’s health and life quality. Endplate chondrocytes can respond to mechanical stimulation, which is an important factor affecting endplate degeneration. Inappropriate mechanical stimulation will accelerate endplate degeneration. This review summarized the effects of mechanical stimulation on vertebral endplate chondrocyte apoptosis, synthesis inhibition, calcification, and extracellular matrix degradation. The endplate degeneration induced by mechanical stimulation is regulated by a complex network of signal pathways composed of various signal transduction factors. The signal pathways involved in this review included NF-κB, Wnt, Hedgehog, MAPK, RhoA/Rock-1, AKT/mTOR, TGF-β signaling pathway and miRNA related signals. The interconnection of these pathways was highlighted and summarized. Multiple signaling pathways work together to regulate endplate chondrocyte metabolism, which ultimately leads to the endplate degeneration. This review might shed light on early diagnosis and precise treatment of cartilage endplate degeneration.
ABSTRACT
OBJECTIVE: Using alendronate after spinal fusion is a controversial issue due to the inhibition of osteoclast mediated bone resorption. In addition, there are an increasing number of reports that the endplate degeneration influences the lumbar spinal fusion. The object of this retrospective controlled study was to evaluate how the endplate degeneration and the bisphosphonate medication influence the spinal fusion through radiographic evaluation. METHODS: In this study, 44 patients who underwent single-level posterior lumbar interbody fusion (PLIF) using cage were examined from April 2007 to March 2009. All patients had been diagnosed as osteoporosis and would be recommended for alendronate medication. Endplate degeneration is categorized by the Modic changes. The solid fusion is defined if there was bridging bone between the vertebral bodies, either within or external to the cage on the plain X-ray and if there is less than 5degrees of angular difference in dynamic X-ray. RESULTS: In alendronate group, fusion was achieved in 66.7% compared to 73.9% in control group (no medication). Alendronate did not influence the fusion rate of PLIF. However, there was the statistical difference of fusion rate between the endplate degeneration group and the group without endplate degeneration. A total of 52.4% of fusion rate was seen in the endplate degeneration group compared to 91.3% in the group without endplate degeneration. The endplate degeneration suppresses the fusion process of PLIF. CONCLUSION: Alendronate does not influence the fusion process in osteoporotic patients. The endplate degeneration decreases the fusion rate.
Subject(s)
Humans , Alendronate , Bone Resorption , Lumbar Vertebrae , Osteoclasts , Osteoporosis , Retrospective Studies , Spinal FusionABSTRACT
Objective To determine the correlation between the Modic degeneration of lumbar endplate on MRI and the pain provocation or degeneration of lumbar intervertebral discs observed on CT discography. Methods One hundred and twenty lumbar intervertebral discs (40 L3-4, 40 L4-5, 40 L5S1 intervertebral discs) of 40 patients among 45 patients were examined. 120 intervertebral discs underwent discography guided by CT scan, according to Dallas Discography Description system, degeneration of lumbar intervertebral disc were divided into 0-3 grade, and pain provocation were graded into negative, indifferent and positive. On the basis of Modic classification system of the lumbar endplate changes and Pearce classification system of the degeneration of lumbar intervertebral disc, the lumbar endplate changes were divided into 0-3 grade, the degeneration of lumbar intervertebral disc were graded into Ⅰ-Ⅴ. All the results were analysed by Chi-Square test for the correlations. Results There was positive correlation between pain provocation test and the lumbar endplate Modic degeneration; There was a positive correlation between the Modic degeneration of lumbar endplate and the degeneration of lumbar intervertebral disc and so is the relation between the CT discography and MRI on discs. Conclusion There is positive correlation between pain provocation test and the Modic degeneration of lumbar endplate, it suggest the endplate might be one of the sources of low back pain. There is a positive correlation between the Modic degeneration of lumbar endplate and the degeneration of lumbar intervertebral disc.