An alternative to lumbar fusion. The worn disc is removed and replaced with a device that lets the level keep moving, instead of joining the two vertebrae into one solid segment. The selection criteria are very narrow: most patients considering it are better served by another option, and candidacy is decided on imaging.
Artificial Disc Replacement in the Lumbar Spine. Licensed patient-education animation, ViewMedica.
A fusion treats a painful lumbar level by stopping it from moving. That works, and it is the right operation for many people, but it also shifts load to the levels above and below. That is the reason to preserve motion where the anatomy allows it.
Disc arthroplasty removes the disc from the front and puts a moving implant in its place, so the segment can still bend forward and back. The decompression is the same as with a fusion; the difference is what is left in place afterwards.
Lumbar disc arthroplasty construct. Anterior view of the implant seated in the prepared disc space, with the vertebral endplates above and below, contrasted against a fused level.
Low back pain coming from a single worn disc, in a patient whose anatomy is otherwise healthy. The pain has to be coming from the disc itself, and not from the facet joints, the sacroiliac joint or a nerve root, so a careful workup is essential.
An artificial disc only works if the rest of the segment is healthy. The implant replaces the disc, but it cannot repair facet joints that are already arthritic or correct instability, and it needs strong bone to hold it. Each of these rules some people out, and together they rule out most.
Most patients who come in asking about a lumbar disc replacement are not candidates for one. That is what the imaging usually shows, and Dr. Zaidi will tell you early in the consultation.
Any one of these generally rules it out, and they are assessed on imaging.
This list is not complete and does not replace a consultation. Candidacy depends on findings that cannot be judged from symptoms alone.
Which is better depends on the patient. A fusion can do things an artificial disc cannot, which is why candidacy for arthroplasty is narrow. See how the approach is chosen.
The disc is reached from the front, through the abdomen, without going through the back muscles. This gives direct access to the disc space without disturbing the joints at the back that the implant depends on.
Anterior lumbar exposure. The retroperitoneal corridor to the anterior disc space, with the great vessels mobilized and the disc space prepared for implant seating.
Lumbar disc arthroplasty. Discectomy through the anterior corridor, endplate preparation, and the implant seated with the level still articulating through flexion and extension.
Recovery after an operation from the front differs from recovery after one from behind, and it depends on the level treated and on you. Dr. Zaidi will go through what to expect at your consultation.
Recovery after this operation varies from person to person, and no timeline can be guaranteed.
Candidacy is decided on imaging, so please bring any MRI or CT you already have.