ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland.
Swiss Med Wkly. 2012 May 31;142:w13598. doi: 10.4414/smw.2012.13598. eCollection 2012.
The "gold standard" for treatment of intervertebral disc herniations and degenerated discs is still spinal fusion, corresponding to the saying "no disc - no pain". Mechanical prostheses, which are currently implanted, do only have medium outcome success and have relatively high re-operation rates. Here, we discuss some of the biological intervertebral disc replacement approaches, which can be subdivided into at least two classes in accordance to the two different tissue types, the nucleus pulposus (NP) and the annulus fibrosus (AF). On the side of NP replacement hydrogels have been extensively tested in vitro and in vivo. However, these gels are usually a trade-off between cell biocompatibility and load-bearing capacity, hydrogels which fulfill both are still lacking. On the side of AF repair much less is known and the question of the anchoring of implants is still to be addressed. New hope for cell therapy comes from developmental biology investigations on the existence of intervertebral disc progenitor cells, which would be an ideal cell source for cell therapy. Also notochordal cells (remnants of the embryonic notochord) have been recently pushed back into focus since these cells have regenerative potential and can activate disc cells. Growth factor treatment and molecular therapies could be less problematic. The biological solutions for NP and AF replacement are still more fiction than fact. However, tissue engineering just scratched the tip of the iceberg, more satisfying solutions are yet to be added to the biomedical pipeline.
治疗椎间盘突出症和退行性椎间盘的“金标准”仍然是脊柱融合术，这对应着“无椎间盘 - 无疼痛”的说法。目前植入的机械假体只有中等的成功效果，并且具有相对较高的再次手术率。在这里，我们讨论了一些生物椎间盘置换方法，根据两种不同的组织类型（髓核和纤维环），至少可以分为两类。在髓核置换方面，水凝胶已经在体外和体内进行了广泛的测试。然而，这些凝胶通常在细胞相容性和承载能力之间存在权衡，仍然缺乏同时满足这两个条件的凝胶。在纤维环修复方面，我们知之甚少，植入物的固定问题仍有待解决。细胞治疗的新希望来自于对椎间盘祖细胞存在的发育生物学研究，这些细胞将是细胞治疗的理想细胞来源。此外，脊索细胞（胚胎脊索的残留物）最近也重新引起了关注，因为这些细胞具有再生潜力，可以激活椎间盘细胞。生长因子治疗和分子治疗可能不那么成问题。用于 NP 和 AF 置换的生物解决方案仍然更多是虚构的，而不是事实。然而，组织工程只是触及了冰山一角，更多令人满意的解决方案将被添加到生物医学管道中。
