The Biomechanical And Clinical Research Of The Morphometric Change Of L_2/3 Interforamina After L_4/5lumbar Artificial Disc Replacement

It is estimated that 95% of the sciatica and 50% of the Low back pain (LBP) was resulted from lumbar disc herniation,and it possibly lead to vertebral canal narrow. The patients with poor outcome of conservative treatment often required surgical intervention. Currently, discectomy is the common method . Although the symptoms may relief or disappear in most conditions, about 5%~20% of cases the symptoms persist, sometimes deteriorate. Discectomy possibly break the stability of spine, lead to segment instability, then affect the nerve roots. The best approach is to develop an instrument or a therapeutic method to accord with the disc physiological functions, that is to adopt a method for disc functional reconstruction, now it has become a hotspot of research. Lumbar artificial disc replacement(ADR) can restore the basic motion of the intervertebral segment and protect the adjacent levels against unphysiologic loading, is a more physiologic method of treating lumbar DDD, now it has become a hotspot of research.The lumbar intervertebral foramen is a tear shaped, and is bound superiorly and inferiorly by the pedicles of the adjacent vertebrae. the posterior boundary is consisted of the pars interarticularis, ligamentum flavum, and superior articular process, the anterior boundary is formed by the posterior margin of the vertebral bodies and the intervertebral disc.