The lumbar spine models feature as follows: normal "bulging" herniated disc bone and disc degeneration advanced osteoporosis with marked bone compression and bone spurs. Spine models do not dissect but can be removed for individual inspection and study. Ideal for demonstrating anatomy and degeneration of the spine. Made of high quality, unbreakable PVC plastic Includes removable patient education cards. This model set features four life-size, two-piece lumbar vertebrae models in different stages of degeneration.