Discectomy - Indications, Types, Investigations, and Recovery

Why Is a Discectomy Necessary?

Patients with herniated intervertebral discs need discectomy to relieve pain. The spine has individual bones called vertebrae stacked upon each other to form a column through which the spinal cord (extension of the brain) passes.

Fibrous cartilage in the shape of a disc is present between the vertebrae for a cushioning effect and allows the vertebral column to bend without injury to the spinal cord. This disc has a tough outer ring called annulus fibrosus and a soft jelly in the center known as nucleus pulposus.

A disc begins to herniate when the center nucleus pushes against the outer ring due to wear and tear, sudden injury, or metastasis (spreading cancer from its origin to other body parts). This pressure on the outer ring compresses the spinal cord and nearby nerve roots, causing pain. In a discectomy, parts of the herniated disc are removed to relieve pain.

What Are the Different Types of Discectomy?

Based on the time of the discectomy, it can be classified as follows:

Emergency Discectomy - Done in patients with cauda equina syndrome and progressive motor deficit.

• Cauda Equina Syndrome - Cauda equina is a sack of nerve roots at the lower end of the spinal cord. They are responsible for the movement and sensation of the legs and control the bladder. In case of a ruptured disc, a tumor, infection, or fracture, the cauda equina gets compressed, affecting the control of the bladder and sensation of the legs.

• Progressive Motor Deficit - This is seen in patients with lacunar stroke, where the artery supplying the thalamus and basal ganglia gets blocked.

Elective Discectomy- It is done in patients with radicular symptoms (nerve pinching) in the neck, thoracic or lumbar.

Based on the technique, it can be divided as follows:

• Microdiscectomy- It is a minimally invasive procedure where the surgeon uses a specially designed microscope to illuminate and magnify the surgical site. A small incision is made at the affected part of the spine; the underlying muscles are retracted, followed by laminectomy (removal of part of the vertebra called the lamina).Next, the ruptured disc is identified and removed. The layers of the tissue and skin are sutured back along with the dressing. It is considered the gold standard for removing disc herniations.

• Percutaneous Discectomy- A small percutaneous probe is inserted through a needle puncture in the skin; the probe is then inserted into the disc, and herniated part of the disc is removed. This style of removing only the affected part of the disc is known as sequestrectomy. It is an effective surgery for sciatica.

• Endoscopic Discectomy- This technique uses an endoscope to visualize the surgical field on a monitor; specialized instruments are inserted through the endoscope to remove the herniated disc.

Based on the location, a discectomy is performed, it can be divided as follows:

• Lumbar Discectomy - It is done to repair a herniated disc in the lower back (L1-L5).

• Cervical Discectomy - Herniated discs in the neck are repaired in this procedure (C1-C7), which can be done both anteriorly and posteriorly.

• Thoracic Discectomy- Mostly done laterally to repair the herniated disc in the thorax (T1-T12)

What Are the Investigations Done Before Discectomy?

• X-rays.

• CT scans.

• MRI (magnetic resonance imaging).

• Myelogram.

Are There Any Alternative Treatments to a Herniated Disc?

Initial treatment of a herniated disc is always nonsurgical. They include the following:

• Rest - One to two days of bed rest will help relieve back or leg pain if the problem is caused due to strenuous activity.

• Nonsteroidal Anti-inflammatory Drugs - Drugs like ibuprofen and naproxen can help relieve pain.

• Physical Therapy - Specialized exercises help to strengthen back and abdominal muscles, which might relieve pain, especially in cases where a herniated disc is caused due to prolonged sitting.

• Epidural Steroid Injection - Corticosteroid injections provide short-term pain relief by reducing inflammation.

A careful evaluation is done before considering discectomy; it is recommended in patients only after all the nonsurgical treatments cannot relieve the pain symptoms.

What Happens to Space After the Disc Is Removed?

The principle of a discectomy procedure is to remove the herniated or damaged portion of the disc. Only part or the complete disc might be removed depending on the damage. Once the disc is removed, it is necessary to provide additional support to the removed portion of the spine. This is done by spinal fusion.

In this stabilization process, the surgeon may use bone grafts, synthetic materials, and instruments like screws and rods. This creates a bridge between the adjacent vertebrae that eventually grows into a solid column of bone to provide the desired strength.

What Are the Risks of Discectomy?

Specific complications after a discectomy include the following:

• Poor Outcome - In a few patients, surgery may not relieve the symptoms; this may happen due to various reasons like improper technique, non-compliance of the patient post-surgery, etc.

• Nerve Injury - Nerve root injuries can occur during vigorous retraction in large disc herniations; a few cases with cerebrospinal fluid leakage from injury to the spinal cord have also been reported.

• Recurrent Disc Herniation (RDH) - The incidence of RDH is between 5 to 18%; risk factors include young age, lack of sensory or motor deficit, etc.

• Thromboembolism - Obstruction of blood flow due to a blood clot is known as thromboembolism. It is a significant complication in patients undergoing any spine surgery.

• Infections - Complications are often due to infections in patients with predisposing conditions like diabetes, rheumatoid arthritis, liver damage, etc.

How Does Discectomy Recovery Work?

Post-surgery, the patient will be prescribed medication manage pain; a brace or a corset might provide extra support to the back. A few tips to help with recovery include the following:

• Sitting - Start with 20 minutes of sitting per day; the time can be gradually increased, which helps with posture post-surgery.

• Walking - It helps regain mobility and reduces the chances of scar tissue formation.

• Rehabilitation - The surgery aims to reduce pain and return to daily life activities; this can be done only by proper rehabilitation with the help of a qualified physiotherapist.

Conclusion

The best outcome in discectomy is achieved through a multidisciplinary approach involving a neurosurgeon, an orthopedic surgeon, a physician, a registered nurse, and a physical therapist. It is a well-tolerated procedure, and patients often experience pain relief early on. With proper physical therapy, the patient will be able to gain strength and resume normal activities in a few weeks.