Lumbar disc arthroplasty.

Degenerative disc disease is the leading cause of pain and disability in adults in North America, and spinal fusion is the standard treatment. Despite this, it has been discussed among surgeons that (1) spinal fusion deserves reexamination in terms of its long-term consequences and benefits and (2) modern clinical research and development in disc arthroplasty strongly supports its emergence as an alternative. The ability to relieve pain by maintaining motion may be a critical factor in obtaining not only greater pain relief but in preventing adjacent segment degeneration. Early research in arthroplasty devices was promising but cut short. New knowledge in the functional anatomy and biomechanics of the spine has made possible the development of modern arthroplasty devices (eg, Charite Artificial Disc, ProDisc, Maverick device, FlexiCore device) of different constructions and materials (metal-on-plastic, metal-on-metal) and various ranges of motion/mobility that provide a basis for a classification of spinal mode and an assistance in implant selection. Current research also is confronting the critical obstacles of wear and tear and axial compression. Several devices currently are in clinical trials. A detailed review of their characteristics shows the exciting progress of a new treatment era of total disc replacement in spine-lumbar disc arthroplasty.