I've compiled some information on the M6-L artificial disc replacements. The most important thing my surgeon, Mr. Boeree, told me about the M6 is it's 'constrained' and 'graded resistance', which means that the more you twist or bend the disc, the more resistance it puts against that direction of movement. This is unlike the charite or prodisc that allow for a dangerously free range of motion that isn't restricted.
