I Googled them for you I hope this heps

1) broad-based protrusion: Herniation of disc material extending beyond the outer edges of the vertebral body apophyses over an area greater than 25% (90 degrees) and less than 50% (180 degrees) of the circumference of the disc. See protrusion. Note: Broad based protrusion refers only to discs in which disc material has displaced in association with localized disruption of the anulus and not to generalized (over 50% or 180 degrees) apparent extension of disc tissues beyond the edges of the apophyses. If the base is less than 25%, it is called "focal protrusion." Apparent extension of disc material, formation of additional connective tissue between osteophytes, or overlapping of non-disrupted tissue beyond the edges of the apophyses of over 50% of the circumference of the disc may be described as bulging. See: bulging disc, focal protrusion



2) What is lumbar spinal stenosis?

The lumbar spine is made up of five vertebral bodies in the lower back. Nerves coming off the spinal cord travel though the spinal canal and exit the canal through small openings on the sides of the vertebral called foramen. Lumbar stenosis (spinal stenosis) is a condition whereby either the spinal canal (central stenosis) or vertebral foramen (foraminal stenosis) becomes narrowed. If the narrowing is substantial, it causes compression of the nerves, which causes the painful symptoms of lumbar spinal stenosis.