In this segment, Drs. Marré and Chesnut review the world literature on techniques and results of fusion surgery performed primarily for low back pain.  Dr. Marré’s presentation focuses on the influence of surgical approaches and instrumentation techniques on reported outcomes, while Dr. Chesnut’s lecture is on findings of several comparison studies on surgery for low back pain. Special consideration is given to attempts at explaining the sometimes conflicting findings in these studies. From the Series:Symposium on Low Back Pain