Degenerative lumbar spondylolisthesis with spinal stenosis: a prospective long-term study comparing fusion and pseudarthrosis. - Kornblum MB; Fischgrund JS; Herkowitz HN; Abraham DA; Berkower DL; Ditkoff JS; Kornblum, Martin B; Fischgrund, Jeffrey S; Herkowitz, Harry N; Abraham, David A; Berkower, David L; Ditkoff, Jeff S (Spine (03622436), 2004)