Anatomy & Background
An intervertebral disc is a fibrocartilaginous structure found between the bodies of vertebra. These discs are located between each pair of vertebra in the spine.
Think of this disc as being a jelly doughnut: there is a series of fibrous rings on the outside and a soft inside. The outer annular rings are thinnest posterior and lateral; most disc herniations occur at this location due to the weakness of the disc wall. The disc functions as a cushion, allows for movement, and serves as a cartilaginous joint between adjacent vertebrae.
Inflammation, damage or degeneration of a disc can cause a range of symptoms, which vary based on the severity of the problem. Disc pathology may produce a loss of back motion, back pain, pain that radiates into the leg and foot, numbness, tingling, lower leg weakness and associated muscle spasms or some combination of these symptoms. The lumbar levels with the highest rate of disc degeneration and herniation are the fourth and fifth (L4-L5), and lumbar fifth and sacrum (L5-S1) levels.
A disc herniation occurs when the outer walls of the intervertebral disc are torn. Other terms for this condition are ruptured disc, prolapsed disc, or slipped disc. When outer annular rings are torn, the center gel-like nucleus can push out and place pressure on the other structures in the area. The herniation usually occurs at the posterior lateral wall where the annulus fibrosis is thinnest. Unfortunately this is where the nerves of the spine exit and track distally into the body. The larger the tear, and the further the nucleus pushes out into the surrounding area, the more severe the symptoms.
Causes of a Herniated Disc
- Degeneration or general wear-and-tear, which can break down the walls of the disc.
- Repetitive bending and twisting motions especially in combination. These motions places the most stress on the outer fibrous rings.
- Discs are most susceptible to injury in the sitting or bending position as the pressure on the disc is displaced to the front, pushing the contents of the disc posterior laterally toward the thinner and weaker annulus fibrosis.
- A sudden fall or trauma, like a motor vehicle accident.
- Genetic factors may contribute to the likelihood of intervertebral disc disease.
- Smokers are more susceptible to disc herniation and degeneration.
When a disc is herniated the symptoms will depend on the location of the herniation and what soft tissue structures are affected. Symptoms can vary from none at all or very mild if the disc is the only structure involved, or can be more severe. Other symptoms can include:
- Pain in the back or radicular to the buttock into the leg down to the foot if the disc presses on the nerve root.
- Sensory changes like numbness or tingling if the nerve is compromised.
- Weakness can occur if the motor portion of the nerve is effected by the disc’s condition. In severe cases paralysis may even occur.
- Diminished reflexes.
- Muscle spasms and changes in posture in response to the injury.
- Loss of motion including inability to bend or stand straight, and poor tolerance to sitting.
- Standing and walking can be difficult if the herniation is severe. Often the patient will present with a shifted posture and have difficulty finding a comfortable position
Please note: A patient with a herniation may be symptom free if the disc does not press on a sensitive soft tissue structure.
Treating Disc Herniation
Treatment of a disc herniation or injury will depend on the severity of the condition. When treating acute disc or back problems treatment options include:
- Rest. Avoid the activities that produce the pain like bending, twisting, lifting and prolonged sitting.
- Anti-inflammatory drugs and other pain medications.
- Apply ice to the lumbar spine to help reduce pain and associated muscle spasms. Apply ice right away and then at intervals for about 20 minutes at a time. Do not apply directly to the skin.
- An exercise regiment designed specifically to address the cause of the symptoms.
- Physical therapy for back and disc problems must remain conservative at the beginning to avoid aggravating the condition. Your physical therapist should emphasize rest, reducing the inflammation and increasing the blood circulation for healing. Once the initial inflammation has been reduced, a program of stretching and strengthening will be initiated to restore flexibility to the joints and muscles involved, while improving strength and stability of the spine. Each program will be based on the structure causing the problem and symptoms. A program not tailored to the specific problem may aggravate symptoms.
- Bracing or the use of supports may be necessary to reduce stress on the disc, muscles and lumbar spine.
In mild cases patients found that rest, ice and medication were enough to reduce the pain. Once the pain is reduced, physical therapy is recommended to develop a series of stretching and strengthening exercises to prevent re-occurrence of the injury. Return to activity should be gradual to prevent a flare up of symptoms.
Moderate to Severe Cases
If the problem persists, consulting with your health care provider should be the next step. Your physician will perform a thorough evaluation to determine the possible cause of your symptoms, the structures involved, the severity of the condition and the best course of treatment.
In addition to performing a thorough examination your physician may order the following tests to make a more precise diagnosis:
- X-ray to determine if there is any joint degeneration, fractures, bony malformations, arthritis, tumors or infections present.
- MRI to determine any soft tissue involvement, including visualization of the discs, spinal cord and nerve roots.
- CT scans which can give a cross section view of the spinal structures.
- EMG, which is used to determine nerve involvement or damage.
- Myelogram, which involves the injection of dye into the spinal column followed by an X-ray to visualize the position of and the pressure being applied to the discs.
Medications to consider
Your physician may recommend several medication options individually or in combination to reduce the pain, inflammation and muscle spasm that may be associated with disc injuries.
- Over the counter medications for mild to moderate pain.
- If over the counter medications are not effective your physician may recommend stronger prescription pain medication.
- Anti-inflammatory drugs or prescription NSAIDS (non-steroidal anti-inflammatory drugs) to reduce inflammation following acute injury.
- Muscle relaxers to reduce acute muscle spasm.
- Prescription nerve pain medication designed specifically to reduce nerve damage and pain
- Injections such as facet injections, nerve blocks or epidural injections. These may involve the injection of corticosteroids to a specific structure to reduce local inflammation
Severe or non-responsive disc conditions
In the case of conditions that do not respond to conservative care, surgery may be recommended. If you continue to experience some of the following symptoms, your doctor may recommend you for a surgical procedure:
- Increase in radiating or radicular pain
- Pain or nerve damage that gets worse
- The development of increased weakness.
- An increase in numbness or tingling.
- Loss of bowel and bladder control
Medical Procedures to consider
Injections like facet injections, nerve blocks or an epidural. These may involve the injection of corticosteroids to a specific structure to reduce local inflammation.
- Caudal Epidural Injections
- Facet Joint Injections
- Interlaminar Caudal Epidural Steroid Injections
- Transforaminal Epidural Injections
- Selective Nerve Root Blocks
- Endoscopic Decompression
- Endoscopic Foraminotomy
- Percutaneous Decompression
- IDET Intradiscal Electrothermal Therapy
- Selective Endoscopic Discectomy
- Spinal Cord Stimulator
- Epidural Lysis of Adhesions