Disk Replacement Surgery- An Overview

Introduction:

A lumbar disc replacement is a form of spine surgery that involves replacing a worn-out disc in the lumbar spine with prosthetic devices composed of metal or metal and plastic combination. The spine is made up of bone called the vertebrae stacked on each other with discs between them to cushion against wear and tear during rotation, compression, or other movements. The discs present at the bottom of the spine are termed lumbar discs. Lumbar disc replacement is a major surgery that requires general anesthesia and a hospital stay.

Why Is Lumbar Disc Replacement Surgery Considered?

Lumbar disc replacement surgery is another option to the more common spinal fusion procedure that permanently joins two vertebrae together. One may need lumbar disc replacement mainly to treat lower back pain. Not everyone with lower back pain requires this surgery. The doctor does some tests to check if they are a good candidate for this surgery. Lumbar disc replacement surgery is usually done for those whose back pain comes from one or two discs in their lower spine.

What Are the Symptoms That May Require Lumbar Disc Replacement?

Lumbar disc replacement is one of the major surgical procedures that necessitates the patient to be put under general anesthesia and an in-hospital stay for a certain period. This procedure is generally done for lower back pain. Some people with lower back pain are ideal candidates. The consulting doctor requires specific examinations and evaluations to determine the necessity of this surgery.

In general, a lumbar disc replacement surgery might be recommended if the following scenarios are noted;

• If the back pain results from one or two discs in the lumbar spine.

• Presence of no significant joint disease.

• No nerve compression in the spine.

• The patient is not overweight or obese.

• No history of spinal surgeries.

• Scoliosis and other spinal deformities that require fusion surgeries are absent.

What Are the Potential Risks Following Lumbar Disc Replacement Surgery?

Lumbar disc replacement surgery poses some risks, not unlike any major surgical procedure. As disc replacement surgery requires more invasive access to the spine than lumbar fusion surgery, it increases the risk of the process. The potential risks of this artificial disc replacement procedure are as follows:

• Infection of the surgically placed prosthetic disc.

• Infection of the surgical site or incision.

• Dislocation.

• Dislodging.

• Implant failure.

• Fracture.

• Loosening or wearing out of the prosthetic disc.

• Spinal stenosis.

• Poorly positioned implant or poorly performed surgery.

• Rigid spine.

• Clotting of blood in the lower limbs due to reduction in activities.

• Risks associated with pre-existing diseases.

What Are the Preoperative Preparations Before Disc Replacement Surgery?

The consulting physician conducts a physical exam and records the medical history.

The patient may require medical imaging methods before the artificial disc replacement procedure, which are listed below:

1. X-rays.

2. Magnetic Resonance Imaging (MRI) scan.

3. Computed tomography (CT) scan.

4. Blood tests: Total leucocyte count, differential leucocyte count, lipid profiles, blood sugar estimation, and other routine blood tests may be necessary before the procedure.

These tests help identify the nature and extent of the symptoms and the spinal damage caused by them. A better spine view is also necessary to decide whether the surgery suits the patient. The patient may be asked to quit smoking as a part of preoperative preparation before the procedure.

The doctor must be informed of any medication, supplements, and others, as these may affect the healing and blood clotting in the postoperative recovery phase. The patient may be asked to discontinue them before the procedure.

The patient might be instructed to avoid consuming food or drinks for a few hours prior to the procedure, requiring a few days of in-hospital stay during recovery. Activities like driving might also be forbidden postoperatively, and the a need for some help at home with mundane activities such as bathing, dressing, cleaning, and shopping.

What Does A Lumbar Disc Replacement Procedure Involve?

1. An intravenous line is put into a primary vein in the hand or arm.

2. An anesthetic is administered through this channel.

3. A surgical team consisting of a vascular surgeon and an orthopedic or neurosurgeon conducts the procedure.

4. An incision is made in the abdomen.

5. The organs and blood vessels are moved out of the way to allow access to the spine.

6. The damaged disc is removed.

7. An artificial disc is placed.

8. The displaced organs and blood vessels are then returned to their original place.

9. The incision is closed and sutured.

10. The patient is then taken out of surgery into the recovery area.

11. This is done to ensure close monitoring until the anesthesia wears off.

12. The intravenous line will be preserved to administer drugs and fluids.

13. The patient's bladder may need to be catheterized to make urination easier.

14. Once awake and alert, the patient is taken to their hospital room.

The majority of artificial disc replacement procedures require two to three hours.

What Design and Materials Are Utilized in Artificial Disc Replacement?

Certain devices for replacing spinal discs involve keeping the intervertebral disc's outer ring (annulus) intact while replacing the center (nucleus). However, this approach is still being studied. In many cases, complete artificial disc replacements substitute the nucleus (gel-like core) and annulus (outer fibrous ring) with a mechanical device designed to mimic the spine's natural function. There are many different disc designs, each with its special characteristics.

Materials Used - Artificial discs aim to replicate the dimensions and operation of a typical intervertebral disc. Artificial discs can be made of different materials, such as metal or a combination of metal and plastic, resembling joint replacements in the knee and hip. The materials include medical-grade plastic (polyethylene) and medical-grade cobalt chromium or titanium alloy.

What Are the Postoperative Steps Following Lumbar Disc Replacement Procedure?

A few days of in-hospital stay may be needed postoperatively in the recovery phase.

• The healing of the bone is not necessary for a lumbar disc replacement. So, it makes postoperative recovery faster than other spine surgeries.

• Medication to relieve pain is prescribed, and the patient is encouraged to stand and walk after a few days following surgery.

• Opioids may be prescribed, but only in cases of intense pain and not for a continued period, as this may lead to dependence and withdrawal.

• Physical therapy may also be recommended. Initially, the patient will need help with everyday tasks like dressing and bathing.

• The dependency will decrease with time, thus improving the quality of life. Specific strengthening exercises will also be prescribed.

• Specialized shoes or orthotics and devices such as canes and walkers may also be prescribed for a limited period.

Conclusion:

A lumbar disc replacement is a form of spine surgery that involves replacing a worn-out disc in the lumbar spine with metal or metal and plastic prosthetic devices. The spine comprises the vertebrae stacked on each other with discs between them to cushion against wear and tear during rotation, compression, or other movements. A few days of in-hospital stay may be needed postoperatively in the recovery phase. An artificial disc replacement does not require the healing of the bone, and this makes postoperative recovery faster than other spine surgeries.