What is a Herniated Disc?
Herniation of the nucleus pulposus (HNP) occurs when the nucleus
pulposus (gel-like substance) breaks through the anulus fibrosus
(tire-like structure) of an intervertebral disc (spinal shock
A herniated disc occurs most often in the lumbar region of the
spine especially at the L4-L5 and L5-S1 levels (L = Lumbar, S =
Sacral). This is because the lumbar spine carries most of the body's
weight. People between the ages of 30 and 50 appear to be vulnerable
because the elasticity and water content of the nucleus decreases
The progression to an actual HNP varies from slow to sudden onset
of symptoms. There are four stages: (1) disc protrusion (2)
prolapsed disc (3) disc extrusion (4) sequestered disc. Stages 1 and
2 are referred to as incomplete, where 3 and 4 are complete
herniations. Pain resulting from herniation may be combined with a
radiculopathy, which means neurological deficit. The deficit may
include sensory changes (i.e. tingling, numbness) and/or motor
changes (i.e. weakness, reflex loss). These changes are caused by
nerve compression created by pressure from interior disc material.
Progression of Herniated Disc
The extremities affected are dependent upon the vertebral level at
which the HNP occurred. Consider the following examples:
- Cervical - Pain in the neck, shoulders, and arms
- Thoracic - Pain radiates into the chest
- Lumbar - Pain extends into the buttocks, thighs, legs
Cauda Equina Syndrome occurs from a central disc herniation and
is serious requiring immediate surgical intervention. The symptoms
include bilateral leg pain, loss of perianal sensation (anus),
paralysis of the bladder, and weakness of the anal sphincter.
Diagnosis of a Herniated Disc
The spine is examined with the patient laying down and standing.
Due to muscle spasm, a loss of normal spinal curvature may be noted.
Radicular pain (inflammation of a spinal nerve) may increase when
pressure is applied to the affected spinal level.
A Lasegue test, also known as Straight-leg Raising Test, is
performed. The patient lies down, the knee is extended, and the hip
is flexed. If pain is aggravated or produced, it is an indication
the lower lumbosacral nerve roots are inflamed.
Other neurological tests are performed to determine loss of
sensation and/or motor function. Abnormal reflexes are noted as
these changes may indicate the location of the herniation.
Radiographs are helpful, but Computed Axial Tomography (CAT) or
Magnetic Resonance Imaging (MRI) provides more detail. The MRI is
the best method enabling the physician to see the soft spinal
tissues unseen in a conventional x-ray.
Herniated Disc : Treatment and Recovery
There are several conservative treatment options that may relieve
the symptoms associated with a herniated disc. These include:
alternate bed rest with ambulation and medications to reduce
inflammation and pain. Non-steroidal anti-inflammatory drugs
(NSAIDs) are often used for this purpose. Physical therapy may be
incorporated into the patient's treatment plan. This might include
exercise, massage, thermotherapy, as well as a device designed to
support the back - a corset, back belt, or brace.
Remember that most patients with a herniated disc will get better
When no improvement is noted after a course of conservative
treatment, surgery might be considered. However, remember that most
patients with a herniated disc will get better without surgery.
A Discectomy is the surgical removal of part or the entire
offending intervertebral disc. Microdiscectomy incorporates the use
of a microscope to magnify the surgical field during removal of the
Whether the treatment course is conservative or operative, it is
important to closely follow the instructions of your physician
and/or physical therapist. Keep your weight close to ideal and
continue to follow the exercise and/or rehabilitative program
designed by your physical therapist at home.