Patent ID: 8870960

Claim:
A method for replacing an intervertebral disc comprising the step of: establishing an operative corridor to an intervertebral disc space via a lateral, trans-psoas surgical approach that leaves the Anterior Longitudinal Ligament (ALL) intact and includes monitoring nerves in the psoas muscle with a neurophysiology based monitoring system to avoid damaging said nerves: preparing the intervertebral disc space for receipt of a disc replacement implant, the disc replacement implant including a first anchor plate with a first surface for contacting a first vertebra adjacent the disc space and a second interior surface having, an articulation recess integrally formed therein a second anchor plate having a third surface for contacting a second vertebra adjacent the disc space and a fourth interior surface, and an intradiscal element integrally joined with the fourth interior surface, the intradiscal element configured to articulate with the articulation recess, the first anchor plate and second anchor plate together having an implant length defined by a distance along an X-axis, the X-axis being generally parallel to the coronal plane when the implant is positioned within the interbody space, an implant width defined by a distance along a Z-axis, the Z-axis being generally parallel to the sagittal plane when the implant is positioned in the intervertebral space, the implant length being between 40 mm and 55 mm and the implant width being between 18 mm and 22 mm; simultaneously introducing the first anchor plate and second anchor plate through the lateral trans-psoas operative corridor into the intervertebral disc space such that the intradiscal element of the second anchor plate cooperates within the articulation recess of the first anchor plate to post-operatively allow motion between the first and second vertebrae.