The operation of spine fusion is long past the experimental stage and is established as a valuable procedure in structural scoliosis, fracture of the spine, destructive disease of the vertebrae, spondylolisthesis and similar conditions. The operation is advised with reserve by many surgeons because the technic is difficult. In the hands of the experienced spine fusion may be accompanied by shock, which at times borders on being dangerous. It therefore occurred to me that it might be possible to circumvent these difficulties and yet attain the primary object of the operation, namely, fusion of the laminae and spinous processes, by employing a simplified technic. The idea originally grew out of my experience in scoliosis. In the very severe types of this deformity one is compelled to do a unilateral fusion, as it is frequently difficult, and sometimes impossible, to expose thoroughly the posterior arches on the convex side of the