The vertebral venous plexus (see spinal cord blood supply) lies outside the dura, and the larger veins of the spinal canal (Batson's plexus) lie anterolaterally. Bleeding encountered during the laminectomy was controlled with bipolar cautery. Oozing from the marrow of the lamina was controlled with bone wax since no bone grafting was anticipated. Bone wax would hinder the fusion of grafted bone.
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