What is the difference between a disc bulge protrusion and herniation?
A bulging disc occurs when dehydration leads to gradual flattening of the disc and an increase in the circumference of the intact annular ring, which then extends beyond the margins of the vertebral body.
Disc protrusion occurs when the gelatinous disc material protrudes focally into tears or fissures within the intact annular shell, causing a focal outpouching of the still intact annular fibers.
Disc herniation refers to extrusion of nuclear material through the disrupted annular shell.