Laminectomy (Subscribe)  

Lumbar disc disease
  as part of open disc excision for acute disc prolapse:
  Cauda equina syndrome
  Neurological deterioration during non-operative treatment
  Failure of non-operative treatment for at least 6 weeks
Spinal stenosis as part of open decompression of spinal canal
  Pain resistant to non-operative treatment (usually mainly back pain)
  Acute neurological consequences...