Decompression of neural structures is required in patients of lumber spinal canal stenosis when they have-
1. Neurogenic claudication affecting their daily activities.
2. Progressive weakness in lower limbs.
3. Cauda Equina Syndrome (Weakness of lower limbs + numbness + difficulty in urination and defecation).
Decompression can be done by conventional laminectomy method or by Microscopic Decompression (ULBD) method.
Laminectomy: Removal of complete lamina and part of facets compressing the nerves.
It is associated with a large incision, more tissue dissection, more blood loss, longer hospital stay, need of supplementary fixation in selected cases.
MIS Decompression or ULBD (Unilateral laminotomy and bilateral decompression) or Over the top decompression:
It is done with the help of microscope or endoscope through a very small incision (2.5-3 cm.)
Its advantages are-