A disc herniation is a common injury in which the shock absorbing cushion-like structure that is located between adjacent spinal bones (known as the intervertebral disc space) becomes displaced, or moved, from its normal location.
Although a disc herniation can affect nearly any spinal level, it’s often found in the low back. This is because the lumbar spine tends to bear most of the brunt of the body weight as it transfers from head down through the spine. As such, the structures that make up the low back— including the discs — are vulnerable to injury.
Here’s what you need to know about disc herniation.
When a disc herniation occurs, the outer fibers of the spinal discs that, when intact, contain the liquid shock-absorbing material, rupture. These outer fibers are called the annulus fibrosus; the inner liquid is called the nucleus pulposus.) Depending on the degree to which your disc is herniated, some of the liquid center may escape and land on a spinal nerve root, causing symptoms.
A condition known as an annular tear is one way the fibers of the annulus fibrosus might fray, and (over time) possibly develop into the place of exit for the nucleus material. An annular tear is often caused by wear and tear, especially when poor posture is also a factor; injury is another cause.
When nucleus pulposus material that escapes from the disc structure proper comes into contact with a nerve root, you may feel pain. You may get other symptoms as well, including numbness, weakness, or an electrical shock or tingling sensation that travels down one leg or arm.
Herniated disc symptoms may vary according to the spinal level that sustains the damage. In general, though, you’ll likely experience one or more radicular symptoms, as defined above.
How does nerve compression that occurs in the lumbar spine result in symptoms that affect one of your appendages?
The answer is based on the anatomy of the nerves. Spinal nerve roots branch from their place just off the centrally located spinal cord into smaller and smaller nerves that go all over the body. Each nerve root is associated with a particular area of the body, and the nerves that arise from each affect only their area. These areas are called dermatomes for nerve transmission of sensations, and myotomes for nerve transmission of motor, or movement, impulses.
Disc herniation most often comes about not from a specific event like an injury or trauma, but rather from the day in and day out way you live your life. Known lifestyle factors that may up your risk for a herniation include smoking, obesity, poor posture, and having a sedentary occupation such as truck driver or office worker, or having a manual labor job that requires repetitive movement of your spine.
When an injury does result in a herniated disc, it may be because you were in a twisted position on impact, or because the impact forced you suddenly into excessive flexion (which is a rounding forward of the spinal column).
Age plays a major role in one’s risk for disc herniation, as well. As we get older, we tend to accumulate degenerative changes in our spinal structures, which can lead to annular tears and disc herniation. Interestingly, a 2002 study published in Surgical Neurology found that the location of a disc herniation changes as people get older. Where most herniations in younger people occur in the low back, with increasing age, they tend to affect higher up in the spine, according to the study.
Discs also tend to dry out as they age, which means for seniors and the elderly, little may be left of the soft, liquid nucleus to herniate (as an acute injury.) A 2012 study published in the British Journal of Neurosurgery found acute disc prolapse, one of the four stages of herniation, to be rare in people of advanced age.
And believe it or not, your gender influences your risk for this injury, with men more vulnerable than women.
Beyond the above-mentioned risk factors, previously existing spine problems, in particular bulging discs and whiplash injuries, may also predispose you for herniation.
As with most spine problems, diagnosing a herniated disc involves a medical history, during which you’ll be asked to describe your symptoms in detail, and a physical exam. Many healthcare providers order one or more diagnostic imaging tests such as MRI, nerve conduction tests and others, as well.
To detect any nerve damage, which may result from a disc herniation, your healthcare provider will probably test for sensations at each dermatome (defined above) level.
Although discectomy surgery is often effective for relieving pain from a herniation, waiting it out for a minimum of six weeks is the standard of care; 90% of lumbar disc herniations resolve with no treatment whatsoever.
with the help of physical therapy may be another option. This works for some people because over time, the nucleus material that escapes from the disc is resorbed by the body.
Consult with your healthcare provider to determine the best treatment route for you.
Conservative treatment for a lumbar herniated disc may include rest; taking pain medication, muscle relaxers, and/or anti-inflammatory medications; having an epidural steroid injection; and/or physical therapy. The goal of medical management (the drug piece in a non-surgical treatment plan) and physical therapy is to reduce the pain. Physical therapy may also help increase your ability to function and to prevent further injury.
Keep in mind that going to physical therapy is not a passive experience on your part. While your treatment plan may consist of a number of different modalities, doing your home exercise program as directed is key for getting the best results possible. That said, a combination of therapies — rather than a focus on just one type — may help speed your recovery.
Disc Herniation Surgery
If you try physical therapy for six weeks but are not getting the pain relief and physical functioning you need, it may be time to consider back surgery. Generally, either a discectomy or a discectomy is done for a herniation.
Advances in health technology have led to the development of minimally invasive spine surgery (MIS). Advantages of MIS include smaller incisions and quicker healing times. (Smaller incisions may translate to fewer infections.)
And, according to authors of a 2017 systematic review, one big advantage of MIS for ambitious surgeons is the ability to market themselves.
Which should you choose?
That decision is best made in a partnership with your healthcare provider, but the review mentioned above compared the evidence for both MIS and open spine surgery to answer just this question. The researchers found that the best quality evidence did not support minimally invasive surgery over open surgery, and this was true for both neck and low back procedures.
But a 2014 Cochrane Back Group review that also compared MIS to traditional back surgery — this time for disc herniation symptoms in the low back only — found that MIS may not relieve leg pain and/or low back pain quite as well as the traditional surgery. This review also found slightly more incidences of rehospitalization with minimally invasive spine surgery. The outcome differences between the two types of surgery were small, though.