Spinal fusion: a combined anterior and supplementary interspinous technique.

"Standard", noninstrumented, techniques of anterior interbody fusion are frequently followed by nonunion and collapse of the intervertebral space, probably because of persistent rocking movements, particularly in the sagittal plane. Elimination of these theoretical movements by supplementing an anterior interbody fusion with a posterior interspinous H-graft and a cerclage wire was considered to be biomechanically attractive without having the disadvantages associated with posterior instrumentation. In a prospective study a solid fusion was obtained at 16 of 17 operated levels, with a mediocre (+/- 50%) fusion as the exception. The height of the intervertebral space was increased at the majority of the fused levels. The technique is only applicable where neural arches are intact. The technique proved to be safe, simple, effective and inexpensive.