What is artificial disc?
An artificial disc is a device that is implanted into the spine to imitate the functions of a normal disc.

What is artificial disc replacement?
Artificial disc replacement surgery involves replacing a painful disc with an artificial disc. Artificial disc surgery may be performed on the lower back (lumbar spine) or the neck (cervical spine). Artificial disc replacement surgery is indicated for patients with severe degenerative disc disease (DDD).

What does artificial disc replacement do?
The goal of the Artificial Disc procedure is to restore the intervertebral disc height and neuroforaminal height while restoring physiologic motion in that segment of the spine.

What are the diagnosis?

• MRI
• X-RAYS
• CT SCAN
• PROVOCATIVE DISCOGRAPHY

What is the procedure of the artificial disc replacement surgery?

• The Artificial Disc surgery is approached from the front, with a relatively small incision in the abdomen (usually below the belly button).
• The abdominal organs are then gently moved to the side so that the surgeon can visualize the spine while protecting important anatomic structures. This part of the surgery is usually done by a general surgeon or vascular surgeon with the appropriate skills.
• The spine surgeon then removes the patient’s collapsed, degenerated disc.
• The Artificial Disc is then implanted – first the two endplates, then the core in the middle, using specialized instruments. The two endplates (made of a cobalt chromium alloy) are pressed into the vertebrae above and below the disc space, and teeth along the border of the endplate grip the vertebral bone. A polyethylene core is then placed between the endplates.
• The artificial disc is designed to be held in place by the spinal ligaments and the remaining part of the annulus of the disc as well as the compressive force of the spine. Bending X-rays of patients after the surgery show that the motion of the artificial disc (flexion, extension, side bending and rotation) can closely approximate the normal motion of a healthy disc.

What are the latest disc implants available?

• The Charite disc implantconsists of three separate implant components, with an un-attached biconvex polyethylene central core between two metal concave implants attached to the bony endplates. The plastic center is free to move between both endplates, and moves in and out as the spine bends forward and back.
• For the Prodisc-L disc implant, the convex polyethylene component is fixed directly to the lower metal endplate component and articulates with the concave upper metal component like a ball-and-socket joint. The Prodisc implant is considered more intrinsically stable (“semi-constrained”) than the Charite design (“non-constrained”).
• Two newer implants, not yet available clinically but well into their FDA trials, utilize all-metal constructs with metal-on-metal bearing surfaces and ball-and-socket configurations. These are the Maverick disc (Medtronic) and Flexicore disc (Stryker Spine). A number of other artificial disc implants are less far along in development and the FDA approval process.

What are the recent advances in artificial disc replacement?
Pro Disc Artificial Disc Include:

• An upper plate that attaches to the vertebra above the disc
• A middle insert made of ultra-high molecular weight polyethylene that mimics the moving cushion interior of a healthy disc
• A lower plate that attaches to the vertebra below the disc

The plates are composed of cobalt chromium molybdenum and are sprayed with special titanium plasma that encourages bone growth. The idea is that once you heal, the surrounding bones will grow to envelope the plates, sealing in the artificial disc replacement. In theory, you’ll be good as new once you recover from the procedure.

• The theoretical advantage is that artificial disc replacement will result in improved pain and function with maintenance of some motion at a disc space that otherwise may have been fused solidly by more conventional techniques.
• Equally as exciting is the possibility that genetically-engineered cells may be surgically implanted or injected into a degenerated disc, allowing for regeneration of disc material that can serve as a shock absorber like the disc we are all born with. There is some experience already with the use of engineered cells in reproducing knee cartilage, so the possibility of use in the spine is real.