An artificial facet replacement is a joint prosthesis intended to replace the natural facets by restoring normal (or near-normal) motion while providing stabilization of spinal segments. It is typically used as an adjunct to laminectomy, laminotomy, neural decompression and facetectomy, in lieu of fusion, for treatment of instabilities or deformities of the lumbar spine including: Degenerative disease of the facets; Degenerative disease of the facets with instability; Grade 1 degenerative spondylolisthesis with objective evidence of neurologic impairment; Central or lateral spinal stenosis...