Lumbosacral meninges, spinal cord and nerve roots dissected from behind
Contents of sacral canal, posterior view
The laminae of the fifth lumbar vertebra have been cut away and the entire sacral canal has been opened to expose the meninges, nerve roots and blood vessels within the lower part of the vertebral canal. The paired coccygeal nerves are fused with the filum durae matris spinalis and as a consequence are not clearly visible.
Spinous process vertebra L. IV
Lamina (arch of vertebra) L. IV
Intervertebral joint capsule L. IV - V
Vertebral canal (pointer indicates epidural space from which veins and fat have been removed)
Lamina (arch of vertebra) L. V (cut through)
Intervertebral joint capsule L. V - S. I
Posterior superior iliac spine
Sacral nerve III (pointer on dural sheath of nerve roots)
Posterior internal vertebral venous plexus
Gluteus maximus muscle (partially cut away medially)
Dural filum terminale (paired coccygeal nerve fused with filum and not clearly visible in this specimen)
Sacral nerve V
Margins of sacral hiatus
Coccyx (covered by deep dorsal sacrococcygeal ligament)
Ligamentum flavum
Erector spinae muscle (cut across)
Thoracolumbar fascia
Transverse process of vertebra L. V
Upper pointer: Dura mater Lower pointer: Spinal ganglion