A common cause of lower back and leg pain is a lumbar ruptured disc or herniated disc. Symptoms of a herniated disc may include dull or sharp pain, muscle spasm or cramping, sciatica, and leg weakness or loss of leg function. Sneezing, coughing, or bending usually intensify the pain.
Rarely bowel or bladder control is lost, and if this occurs, seek medical attention at once.
Sciatica is a symptom frequently associated with a lumbar herniated disc. Pressure on one or several nerves that contribute to the sciatic nerve can cause pain, burning, tingling, and numbness that extends from the buttock into the leg and sometimes into the foot. Usually one side (left or right) is affected.
Anatomy: Normal Lumbar Intervertebral Disc
First, a brief overview of spinal anatomy so that you can better understand how a lumbar herniated disc can cause lower back pain and leg pain.
In between each of the 5 lumbar vertebrae (bones) is a disc—a tough fibrous shock-absorbing pad. Endplates line the ends of each vertebra and help hold individual discs in place.
Every disc has a tire-like outer band (annulus fibrosus) that encases a gel-like substance (nucleus pulposus).
Disc herniation occurs when the annulus fibrous breaks open or cracks, allowing the nucleus pulposus to escape.
This is called a herniated nucleus pulposus or herniated disc, although you may have also heard it called a ruptured disc or a bulging disc.
When a disc herniates, it can press on the spinal cord or spinal nerves. All along your spine, nerves are branching off from the spinal cord and travelling to various parts of your body (to help you feel and move).
The nerves pass through small passageways between the vertebrae and discs, so if a herniated disc presses into that passageway, it can compress (or “pinch”) the nerve. That can lead to the pain associated with herniated discs.
Lumbar Herniated Disc Symptoms
General symptoms typically include one or a combination of the following:
- Leg pain (sciatica), which may occur with or without lower back pain. Typically the leg pain is worse than the lower back pain.
- Numbness, weakness and/or tingling in the leg
- Lower back pain and/or pain in the buttock
- Loss of bladder or bowel control (rare), which may be an indication of a serious medical condition called cauda equina syndrome.
L4-L5 and L5-S1 Disc Herniation Symptoms
The vast majority of disc herniations will occur toward the bottom of the spine at L4- L5 or L5- S1 levels. In addition to typical sciatica symptoms, nerve impingement at these levels can lead to:
L5 nerve impingement (at the L4 – L5 level) from a herniated disc can cause weakness in extending the big toe and potentially in the ankle (foot drop).
Numbness and pain can be felt on top of the foot, and the pain may also radiate into the buttock.
S1 nerve impingement (at the L5 – S1 level) from a herniated disc may cause loss of the ankle reflex and/or weakness in ankle push off (patients cannot do toe rises). Numbness and pain can radiate down to the sole or outside of the foot.
Lumbar Herniated Disc Risk Factors
Many factors increase the risk for disc herniation:
- Lifestyle choices such as tobacco use, lack of regular exercise, and inadequate nutrition substantially contribute to poor disc health.
- As the body ages, natural biochemical changes cause discs to gradually dry out, which can affect disc strength and resiliency. In other words, the aging process can make your intervertebral discs less capable of absorbing the shock from your movements, which is one of their main jobs.
- Poor posture combined with the habitual use of incorrect body mechanics stresses the lumbar spine and affects its normal ability to carry the bulk of the body’s weight.
Combine these factors with the affects from daily wear and tear, injury, incorrect lifting, or twisting and it is easy to understand why a disc may herniate.
For example, lifting something incorrectly can cause disc pressure to rise to several hundred pounds per square inch!
How a Disc Herniates
A herniation may develop suddenly or gradually over weeks or months. The 4 stages to a herniated disc are:
1) Disc Degeneration: Chemical changes associated with aging causes discs to weaken, but without a herniation.
2) Prolapse: The form or position of the disc changes with some slight impingement into the spinal canal and/or spinal nerves. This stage is also called a bulging disc or a protruding disc.
3) Extrusion: The gel-like nucleus pulposus breaks through the tire-like wall (annulus fibrosus) but remains within the disc.
4) Sequestration or Sequestered Disc: The nucleus pulposus breaks through the annulus fibrosus and can then go outside the intervertebral disc.
How a Lumbar Herniated Disc is Diagnosed
Interestingly, not every herniated disc causes symptoms. Some people discover they have a bulging disc or herniated disc after an x-ray for an unrelated reason.
Most of the time, the symptoms, especially the pain, prompt the patient to seek medical care. The visit with the doctor usually includes a physical exam and neurological exam.
He or she will also review your medical history, and ask about what symptoms you’ve experienced and what treatments you’ve tried for pain relief.
An x-ray may be needed to rule out other causes of back pain such as osteoarthritis (spondylosis) or spondylolisthesis.
A CT or MRI scan verifies the extent and location of disc damage.These imaging tests can show the soft tissues (such as the disc).
Sometimes a myelogram is necessary. In that test, you will receive an injection of a dye; the dye will show up well on a CT scan, enabling your doctor to more easily see problem areas.
Lumbar Herniated Disc Treatments
In most cases, if a patient’s pain is going to get better it will start to do so within about six weeks.
While waiting to see if the symptoms will abate on their own, several non-surgical treatments can help alleviate the pain and facilitate long term healing. The most common herniated disc nonsurgical treatments include:
- Physical therapy
- Osteopathic/chiropractic manipulation (manual manipulation)
- Heat and/or ice therapy
- Non-steroidal anti-inflammatory drugs (NSAIDs)
- Oral steroids (e.g. prednisone or methyprednisolone)
- An epidural (cortisone) injection
If the pain and other symptoms continue after six weeks, and if the pain is severe, it is reasonable to consider microdiscectomy surgery as an option.
Lumbar Herniated Disc Surgery
A microdiscectomy is designed to take the pressure off the nerve root and to provide the nerve with a better healing environment.
Usually, only the small portion of the disc that is pushing against the nerve root needs to be removed, and the majority of the intervertebral disc remains intact.
Using microsurgical techniques and a small incision, a microdiscectomy can usually be done on an outpatient basis or with one overnight stay in the hospital, and most patients can return to work full duty in one to three weeks.
Recurrent Disc Herniation
Unfortunately, approximately 10% of patients will experience another disc herniation at the same location.
This recurrence is most likely to happen early in the postoperative period (within the first three months), although it can happen years later. Usually a recurrence can be handled with another microdiscectomy.
If it recurs multiple times, a lumbar fusion surgery to stop the motion at the disc level and remove all of the disc material may be considered.