Spine Anatomy Overview Video The lamina is the flattened or arched part of the vertebral arch, forming the roof of the spinal canal; the posterior part of the spinal ring that covers the spinal cord or nerves. Related Definitions Spinal Canal Laminectomy Laminotomy Laminoplasty Editor’s Top Picks Lumbar Laminectomy Surgery for Spinal Stenosis (Open Decompression) Cervical, Thoracic and Lumbar Interlaminar Epidural Injections