Discectomy

Structure of the Vertebral Disc in Brief

The spine or vertebral column is composed of individual bones, termed vertebrae, which rest one on top of the other. In between the vertebrae are discs that provide support by a cushioning effect and allows the vertebral column to bend without the vertebrae touching the spinal cord. However, when the disc becomes diseased, it can become bulged or herniated, thereby compressing the nerves of the spinal cord due to spinal stenosis. This causes localized back pain, neck pain or radiating pain, such as sciatica that spreads down one or both legs. Under such circumstances, the disc needs to be removed by surgery.

What is Discectomy?

Discectomy is the surgical removal of part or all of a herniated or bulging intervertebral disc that presses against a nerve root or the spinal cord itself and causes pain and other symptoms.

The aim of surgery is to achieve decompression by removing bone or soft tissue compressing the contents of the spinal canal. This reduces pain due to a herniated disc that is unresponsive to conventional, non-surgical treatment modalities such as medications, physiotherapy, and epidural injections.

Since the pain originates in the lumbar region, a lumbar discectomy is performed, which is the most common procedure for correcting lumbar-related symptoms. Although lumbar disc herniation accounts for only 5% of back problems, such as radiating lower back pain (lumbar radiculopathy), it is however the major cause of sciatic nerve pain.

Of the various techniques currently available, open microdiscectomy remains the most common, against which the outcomes of other minimally invasive discectomy techniques are compared.

Surgical techniques have advanced from the traditional 'open' surgery. Nowadays minimally invasive procedures use smaller surgical incisions and devices such as microscopes, endoscopes and laser. These operations use a smaller incision, associated with reduced blood loss and damage to nearby tissues. Recovery rate is also quicker.

What are the Types of Discectomy?

• Microdiscectomy: This is a minimally invasive discectomy procedure that uses a specially designed operating microscope that illuminates and magnifies the surgical field. This allows the surgeon to make a very small incision, causing minimal damage to the adjacent tissues. Microdiscectomy is a reliable surgical procedure and considered the gold standard for open discectomy. It offers immediate relief from sciatica due to a lumbar herniated disc.
• Percutaneous Discectomy: In this procedure a small percutaneous probe is inserted through a needle puncture in the skin. The probe is inserted into the disc and a small portion of the central part of the disc is removed. Percutaneous discectomy effectively relieves pain in patients suffering from sciatica or leg pain caused by a herniated or slipped disc.
• Endoscopic Discectomy: In this procedure a small incision is made in the skin and a probe is passed up to the herniated disc. Then an endoscope, which incorporates a light and camera, is inserted through the probe, so that the surgeon can visualize the surgical field on a monitor. Instruments are inserted through the endoscope to perform the surgery.
• Laser Discectomy: This procedure uses a laser beam to penetrate and operate on the herniated disc, but is still in the Research & Development (R&D) stage.

Why is Discectomy done?

Surgery is carried out to reduce the pain and regain mobility and function. Surgical intervention may be considered in the following instances:

• Reduced mobility: Severe pain, accompanied by weakness or loss of sensation in one or both legs, affecting mobility and performance of daily activities.
• Failure of medical treatment: No improvement of symptoms after 4 weeks of non-surgical medical therapy.
• Evidence that surgery may be helpful: Indications from a thorough physical examination that surgery may improve the symptoms.
• Cauda Equina Syndrome: This is a serious condition that occurs due to squeezing of the roots of nerve bundles at the end of the spinal cord (cauda equina). It may be caused by a herniated disc that compresses the entire cauda equina, thereby causing loss of bowel or bladder control, new weakness in the legs, or numbing/tingling in the genital area, buttocks, and legs. Under these situations, emergency surgery is required.

How do you prepare before Discectomy?

Since discectomy is an elective surgery, there is usually ample time to prepare for the operation. The patient can gather information and read-up about the procedure during this preparative period. In case of any doubts, the patient should talk to the surgeon, since the decision for having a discectomy rests with the patient and the surgeon. The procedure is done either by an orthopedic surgeon or a neurosurgeon.

• Once a decision is made to go for the surgery, the surgeon may carry out a thorough physical examination to assess that the patient is in the best possible condition to have the surgery.
• Discectomy is a major procedure and it is important to get all doubts and fears clarified by the doctor. If necessary, a second opinion may be sought.
• A battery of blood tests and urinalysis is carried out to ensure the state of health of the patient and to rule out any chronic underlying diseases.
• If the patient is a smoker, smoking should be stopped several days before the surgery or quit altogether.
• Certain medications such as warfarin and/or aspirin that the patient may be taking will be stopped by the surgeon approximately 2 weeks prior to the surgery. These medications increase the risk of bleeding during surgery.
• The following scans may also be ordered by the surgeon:
• Computed Tomography (CT Scan)
• Magnetic Resonance Imaging (MRI)
• Myelogram
• The patient will be evaluated with the results of these investigations by the cardiologist and anesthetist and pronounced fit for surgery provided there are no serious problems.
• The patient is advised to get admitted to the hospital on the evening before surgery for the administration of certain medications and to perform certain routine blood tests.
• The patient should be on an empty stomach since midnight the previous night.
• On the morning of the surgery, the site of operation is cleaned and any hair over the area is shaved. The patient is provided a clean surgical gown to wear and taken to the operation theater.

What Happens During the Discectomy Procedure?

• Before the surgery, the patient may be made unconscious by administering general anesthesia (GA) or the lower part of the body from the back down may be numbed by spinal anesthesia. Local anesthesia is not recommended for this type of surgery.
• Once the patient is anesthetized, he is turned over to lie down on the front (prone position) with appropriate padding.
• The patient's back is scrubbed with sterile soap so that a sterile field is created, which is then draped before the surgery begins.
• A small incision is made over the region where the disc is herniated. The affected part of the spine is exposed by splitting the muscles from the bones of the spine using dilators and retractors.
• In the next step, a small piece of bone from the vertebra, called lamina, is removed (laminotomy or laminectomy), which creates a small window through which the spinal nerves can be visualized.
• Once the ruptured disc is identified, it is removed along with other fragments of the disc that may have been dislodged or likely to get dislodged.
• The layers of tissue are then sutured and finally the skin incision is sutured.
• At the end of the surgery, a dressing is applied over the incision.

What Happens after the Discectomy?

• After the surgery, the patient is shifted to the recovery room and the vital signs are monitored for a few hours. If they remain stable, the patient will be shifted to his room.
• After the anesthesia wears off, the patient will be given clear fluids.
• When normal bowel function returns, a solid diet will be provided, which usually requires 2 days post-surgery.
• The following day, the patient will be encouraged to sit in a chair for about 20 minutes. Sitting and walking should be limited to 20 minutes to avoid straining the back.
• Prescribed painkillers should be taken to ease the pain. Physical therapy will begin 1 to 2 days after surgery.

• The physical therapist will show how to perform proper body movements and exercises to strengthen the back muscles.
• Braces or a corset may be required to provide extra support to the back.
• After regaining adequate mobility, the patient is usually discharged, subject to regular follow-up during the recovery period.

What are the Risks & Complications of Discectomy?

As with any surgical intervention, there are some risks and complications, although minimal, that may nevertheless be associated with discectomy. These include the following:

• Poor outcome: There is a possibility that the surgery may not improve the condition. This can occur due to various reasons, including the surgical procedure itself. For example, sometimes the surgeon can perform a wrong-level surgery, where the correct vertebra is missed. Proper pre-operative planning and intra-operative vigilance can prevent wrong-level surgery.
• Nerve injury: There is a risk that the spinal nerves may be damaged or injured. Injuries to the dura (covering of the spinal canal) can cause leakage of cerebrospinal fluid (CSF) during the surgery in 3% of cases. Nerve root injury can occur due to vigorous retraction, large disc herniations and conjoined nerve roots. Nerve root injuries after lumbar spine surgery has been reported to occur in 0.2% cases.
• Infections: Complications may arise from infections, if proper precautions are not taken. The infection rate of the disc space after lumbar discectomy can range from 0.13% to 0.9%.
• Anesthesia reactions: The patient must be checked for sensitivity to any of the components of the anesthetic being used. Otherwise, this can cause complications during surgery. However, in a generally healthy patient, the chance of death from this type of surgery is miniscule (< 1:300,000).
• Recurrent disc herniation: The incidence of recurrent lumbar disc herniation that can result in reoperation ranges from 3% to 18% in patients undergoing discectomy for the first time.
• Thromboembolism: Thromboembolic complications can occur during the perioperative period. The reported rate of embolic complications range from 0.1% to 1% and the rate of lower-extremity thrombosis can be higher.
• Other complications: Some other common complications include nerve palsies and compression injuries due to improper positioning, exaggerated limb stretch and inadequate padding.

What are the steps to be taken for Recovery after Discectomy?

During the recovery period, the patient should continue to wear the braces, and should avoid driving for at least 6 weeks, due to both safety and legal reasons. The patient should desist from picking-up objects from the floor by bending at the waist. Instead, bending at the knees is advised, if required. Carrying heavy objects must be avoided. The incision should be kept dry to avoid infections. Sponge baths are recommended until the doctor advises to take regular baths.

Some other important aspects that should be kept in mind during recovery include the following:

• Sitting: Maintaining a sitting posture may be difficult at first. The sitting period can be 20 minutes initially, which can be increased gradually.
• Walking: Walking is encouraged during the recovery period, but it is important not to get overtired. Climbing stairs, if absolutely necessary, should be limited to once daily. Walking will enable regaining mobility quicker and also reduce chances of scar tissue formation.
• Rehabilitation: For those intending to return to daily activities, a rehabilitation program, as advised by the doctor, will continue at home, including physical therapy by a qualified physiotherapist.
• Returning to work: The aim of recovery is to return to normal daily activities which includes returning to work. If engaged in a sedentary job in an office setting, the patient can usually return to work within 2-4 weeks post-surgery. If engaged in manual work involving operation of machinery, joining work may take up to 6-8 weeks. As a general rule, the patient should not return to work without the doctor's permission.

Diet after Discectomy

A normal, well balanced diet rich in protein is recommended. High-protein foods like lean meat, fish, poultry and eggs should be consumed. High-protein diets contain plenty of zinc, which helps to fight infections.

Low-fat dairy products are recommended as they supply calcium and vitamin D, which are essential for bone restoration.

The vitamin C from fruits, as well as other nutrients will help in wound healing and recovery. Drinking plenty of fluids is advised in order to keep well hydrated. Breaking-up the standard 3 meals per day into 5 to 6 "mini-meals" will help to reduce the load on the digestive system. Consuming fruit shakes will help to boost the calorie intake.

In case of a stomach-upset, a bland diet such as plain rice, lentils, chicken stew, toast, and yogurt can be taken. On the other hand, in case of constipation or irregular bowel movements, plenty of dietary fiber in the form of grains, legumes, fruits and vegetables should be consumed. In severe cases, the doctor may prescribe a mild laxative.

As an adjunct to the normal diet, the doctor may recommend taking multivitamin tablets to make-up for any possible deficiencies.

Health Tips

• Quit smoking prior to surgery: If you happen to be a smoker, having a discectomy provides an ideal opportunity to quit. This will not only be beneficial for health in general, but will accelerate the healing process after surgery.
• Do exercises after the surgery as per your doctor's advice: Do the exercises that are recommended by your doctor or physiotherapist. These exercises will help to slowly regain your spine flexibility and improve mobility.
• Eat a balanced diet after surgery: Following surgery, during the recovery period at home, eat a balanced diet rich in proteins, carbohydrates, dietary fibers, vitamins and minerals. This will facilitate the healing process and help you prepare for resuming your daily activities.
• Avoid strenuous exercise: Although mild aerobic exercises like walking is encouraged, you should not attempt to stain your body by lifting heavy objects or any form of strenuous exercise.