Lumbar Discectomy

Anatomy

The lumbar spine is located in your lower back. It forms the curve below your waist. The lumbar spine connects your upper body -- your head, trunk, and arms, to your lower body -- your pelvis and legs. Ligaments and muscles connect to your spinal column. They provide back stability and movement.

Five large vertebrae make up the lumbar area of your spine. The back part of the vertebra arches to form the lamina. The lamina creates a roof-like cover over the back of the opening in each vertebra. The opening in the center of each vertebra forms the spinal canal. Your spinal cord and spinal nerves travel through the protective spinal canal.

Your spinal cord tapers near the first lumbar vertebra and forms a bundle of nerves called the cauda equina. Your spinal cord and spinal nerves at the lumbar spine level send signals for sensation and movement between your brain and leg muscles. The cauda equina is involved with regulating bowel and bladder functions.

There are six intervertebral discs between the vertebrae in your lumbar spine. The discs are made up of strong connective tissue. Their tough outer layer is called the annulus fibrosus. Their gel-like center is called the nucleus pulposus.

The discs and two small spinal facet joints connect one vertebra to the next. The discs and joints allow movement and provide stability. The discs also act as a shock-absorbing cushion to protect the lumbar vertebrae.

Causes

As we age, our discs lose water content. Our discs can become shorter, less flexible, and less effective as cushions between the vertebrae. When a disc deteriorates, the outer layer can tear. A herniated disc occurs when the outer layer ruptures and the inner contents, the nucleus pulposus, come out of the disc.

If the inner contents of a herniated disc extend into the spinal canal, it can cause pressure on the spinal nerves. When the inner contents come in contact with the spinal nerves, a chemical reaction occurs. The spinal nerves become irritated and swell, resulting in pain. A herniated disc can also cause pressure on the spinal cord.

Herniated discs are more common among people that are middle aged. Older adults are at the greatest risk for herniated discs because of their decreased disc water content. Other risk factors include being overweight and smoking. Using poor body posture when lifting or performing repetitive strenuous activities can also cause discs to rupture.
Additionally, a disc can rupture after sudden pressure, even if it is slight. This can occur from trauma during violence, motor-vehicle crashes, or from a sports-related injury, such as football or surfing.

Symptoms

Pain is a common symptom of a herniated lumbar disc. You may experience a shooting pain that extends from your buttocks through the back of one leg. Your leg or buttock may feel weak, numb, or have a tingling sensation.

In rare cases, the loss of bowel and bladder control accompanied by significant leg weakness indicates a possible serious problem. If you experience these symptoms, you should seek immediate medical attention.

Diagnosis

Your doctor can diagnose a herniated disc by performing a physical examination and viewing medical images. Your doctor will ask you about your symptoms and medical history. You will be asked to perform simple movements to help your doctor assess your muscle strength, joint motion, and stability. Since the nerves from the lumbar spine travel to the legs, your doctor will perform a neurological physical exam to see how the nerves are functioning.

Your doctor will order X-rays to see the condition of the vertebrae in your lumbar spine. Dye may be injected into the spinal column to enhance the X-ray images in a procedure called a myelogram. A myelogram can indicate if there is pressure on your spinal cord or nerves from herniated discs, bone spurs, or tumors.

Your doctor may also order Computed Tomography (CT) scans or Magnetic Resonance Imaging (MRI) scans to get a better view of your spinal structures. CT scans provide a view in layers, like the slices that make up a loaf of bread. The CT scan shows the shape and size of your spinal canal and the structures in and around it. The MRI scan is very sensitive. It provides the most detailed images of the discs, ligaments, spinal cord, nerve roots, or tumors. X-rays, myelograms, CT scans, and MRI scans are painless procedures and simply require that you remain motionless while a camera takes the pictures.

In some cases, doctors use nerve conduction studies to measure how well the lumbar spinal nerves work and to help specify the site of compression. Doctors commonly use a test called a Nerve Conduction Velocity (NCV) test. During the study, a nerve is stimulated in one place and the amount of time it takes for the message or impulse to travel to a second place is measured. Your doctor will place sticky patches with electrodes on your skin that covers a spinal nerve. The NCV may feel uncomfortable, but only during the time that the test is conducted.

An Electromyography (EMG) test is often done at the same time as the NCV test. An EMG measures the impulses in the muscles to identify nerve and muscle problems. Healthy muscles need impulses to perform movements. Your doctor will place fine needles through your skin and into the muscles that the spinal nerve controls. Your doctor will be able to determine the amount of impulses conducted when you contract your muscles. The EMG may be uncomfortable and your muscles may remain a bit sore following the test.

Treatment

The majority of people with herniated discs can be treated with non-surgical methods aimed at pain relief. Over-the-counter medication or prescription medication may be used to reduce pain and swelling. If your symptoms do not improve significantly with these medications, your doctor may inject your spinal column with corticosteroid medication. Corticosteroid medication is a relatively safe pain reliever.

Your doctor may recommend that you rest for a few days. Occupational or physical therapists can provide treatments to reduce your pain, muscle spasms, and swelling. The therapists will also show you exercises to strengthen your back muscles.

Surgery

Surgery is recommended when non-surgical methods have provided minimal or no improvement of your symptoms. A Discectomy is a type of surgery used to remove the part of the disc that is putting pressure on the spinal cord or nerves. A Discectomy may be required if a herniated disc is pressing directly on a nerve or the spinal cord and causing considerable pain. Surgery may also be necessary to remove broken pieces of a disc or surrounding bone.

In select cases, a Discectomy can be performed arthroscopically. Arthroscopic surgery uses small specialized tools and a small incision. It can be performed under local anesthesia and has a shorter recovery time than traditional surgery. However, an Open Discectomy is the type of surgery most frequently used for a lumbar herniated disc. This is often done through a small incision and with a microscope and is called a microdiscectony.

You will be sedated for your Open Discectomy surgery. Your surgeon will make an incision, about an inch long, on the middle of your spine. Muscles will be detached from the vertebrae and moved aside with care to expose the disc. In some cases, the lamina on the vertebrae and ligaments need to be removed to allow the surgeon to see and gain access to the disc. If all of the lamina is removed, the procedure is called a Laminectomy. A Laminotomy involves removing only part of the lamina.

Your surgeon will remove the piece of the disc that has come out of the disc wall. Your surgeon will also remove any disc fragments that broke off of the disc. With this type of surgery, no material is used to replace the disc tissue that was removed.

Recovery

You will most likely stay overnight in the hospital following your surgery. You will receive medication to help ease your pain. You will begin walking with supervision as soon as you have recovered from the anesthesia. You will continue exercising with a physical therapist or an exercise program when you have returned home.

Your doctor may restrict a few of your activities at first. For the first four weeks following surgery, you should avoid lifting, sitting for long periods of time, and excessive bending or stretching. You should not drive until your doctor gives you the clearance to do so. Most people with jobs that are not physically challenging return to work fairly quickly. People with jobs that require heavy lifting or involve machinery that causes heavy vibration, such as construction equipment, may need to wait much longer before returning to work.

The recovery process is different for everyone. It depends on the extent of your condition and the type of surgery that you had. Your doctor will let you know what to expect. Overall, research shows that the majority of people achieve good results with Open Discectomy. It appears that people that have surgery to relieve the pain in their legs achieve better results than those that have surgery for just low back pain.

Prevention

It is important that you adhere to your restrictions and exercise program when you return home. Physical therapy may play a role in your recovery.