What's a herniated disc, pinched nerve, bulging disc
Spinal disc pain terminology varies:
There are many different terms used to describe spinal disc pathology and associated pain, such as “herniated disc”, “pinched nerve”, and “bulging disc”, and all are used differently by individual healthcare practitioners. Unfortunately, there is no agreement in the healthcare field as to the precise definition of any of these terms. Often the patient hears his or her diagnosis referred to in different terms by different practitioners and is left wondering if there is any consensus on what is wrong.
Some examples of terms used to describe spinal disc abnormalities include:
- Pinched nerve
- Herniated disc (or herniated disk)
- Bulging disc
- Ruptured disc
- Torn disc (or disc tear)
- Slipped disc
- Collapsed disc
- Disc protrusion
- Disc degeneration
- Degenerative disc disease
- Disc disease
- Black disc
Practical point Individuals’ symptoms of disc degeneration, and their relief from treatments, can vary tremendously, so patients should provide as complete and accurate account of their symptoms as possible to their practitioner so treatment can be customized for them.
Rather than try to reconcile the terminology used to refer to spinal anatomy or conditions, it's generally more useful for patients to gain a clear understanding of the precise medical diagnosis, which identifies the actual source of the patient’s low back pain, leg pain, or other symptoms.
Integrated findings form the medical diagnosis:
A physician’s medical diagnosis (also called “clinical diagnosis”) focuses on determining the source of a patient’s pain. For this reason, the medical diagnosis of a patient’s low back pain, leg pain, or other symptoms is based on more than just the findings from a diagnostic test, such as an MRI scan or CT scan. Instead, the spine care professional arrives at a clinical diagnosis of the cause of the patient’s pain by synthesizing findings from a thorough review of the patient’s medical history, a complete physical exam, and, if appropriate, the results of one or more diagnostic tests.
- Medical history. The physician will take the patient’s medical history, such as a description of when the low back pain, sciatica or other symptoms occur, a description of how the pain feels, and what activities, positions or treatments make the pain feel better, and more.
- Physical exam. The physician will conduct a thorough physical exam of the patient, such as testing nerve function and muscle strength in certain parts of the leg or arm, testing for pain in certain positions, and more. Usually, this series of physical tests will give the spine professional a good idea of the type of back problem or neck problem that the patient has.
Diagnostic tests. After the physician has a good idea of the source of the patient’s pain, a diagnostic test, such as a CT scan or an MRI scan, is often ordered to confirm the presence of an anatomical lesion in the spine. The tests can give a detailed picture of the problem, such as the location of the herniated disc and impinged nerve roots. Some practitioners advocate more extensive diagnostic tests and will recommend a discogram in order to develop as much information as possible about the patient’s condition. However, this test is expensive and somewhat painful because it is a ‘provocative’ test (i.e., it is designed to provoke pain responses in the patient to locate the area of pain generation).
For these reasons, many doctors will refrain from using discography unless necessary. Although the anatomic findings on an imaging study bear certain significance, they are not in and of themselves diagnostic. There can be lesions present on an imaging study that are not symptomatic. And while it may be troubling for a patient to have the knowledge that their disc health is compromised, most people will have some level of disc degeneration by the time they reach 60 years of age. A patient’s physical exam findings and symptoms need to match the anatomic findings to arrive at an accurate medical diagnosis and, more importantly, an effective treatment plan.
Medical diagnosis determines the pain generator:
The key factor in the clinical diagnosis is to determine if the patient has a pinched nerve or if the disc space itself is generating the pain. These two common conditions produce a different type of pain.
- Pinched nerve: When a patient has a symptomatic herniated disc, it is not the disc space itself that hurts, but rather the disc herniation is pinching a nerve in the spine. This produces pain that is called radicular pain (e.g., nerve root pain, or sciatica from a lumbar herniated disc, or arm pain from a cervical herniated disc).
This type of condition is referred to as a herniated disc.
- Disc pain: When a patient has a symptomatic degenerated disc (one that causes low back pain or other symptoms), it is the disc space itself that is painful and is the source of pain. This type of pain is typically called axial pain.
This type of condition is referred to as a degenerative disc disease.
It should be kept in mind that all the terms – herniated disc, pinched nerve, bulging disc, slipped disc, ruptured disc, etc.– refer to radiographic findings seen on a CT scan or MRI scan (x-rays can indicate disc degeneration but cannot actually image the disc itself). While radiographic findings are important, they are not as meaningful in determining the source of the pain (the clinical diagnosis) as the patient's specific symptoms and the spine specialist's findings on physical exam.
Pinched nerve pain and disc space pain treatments differ:
It's critical to accurately diagnose the pain generator, because the type of pain created by the spinal disc dictates the type of treatment, and the treatments for the different diagnoses vary considerably. For example, treating a lumbar herniated disc will not do the patient much good if it is a muscle strain or other soft tissue injury rather than the disc herniation that is the cause of the patient’s pain. This is particularly important for patients who might be considering surgery. Surgical intervention can only treat anatomic anomalies that have been shown to generate pain; surgery is not appropriate in cases where disc degeneration—even severe disc degeneration – may not be the cause of a patient’s pain, or in situations where the patient has chronic pain but the exact source cannot be adequately identified.
Understanding the clinical diagnosis of a herniated disc
Integrated findings form the clinical diagnosis:
A physician’s clinical diagnosis focuses on determining the source of a patient’s pain. For this reason, the clinical diagnosis of pain from a herniated disc is based on more than just the findings from a diagnostic test, such as an MRI scan or CT scan. Instead, the spine care professional arrives at a clinical diagnosis of the cause of the patient’s pain through a combination of findings from a thorough medical history, conducting a complete physical exam, and, if appropriate, conducting one or more diagnostic tests.
· Medical history. The physician will take the patient’s medical history, such as a description of when the low back pain, sciatica or other symptoms occur, a description of how the pain feels, what activities, positions or treatments make the pain feel better and more.
· Physical exam. The physicians will conduct a thorough physical exam of the patient, such as testing nerve function and muscle strength in certain parts of the leg or arm, testing for pain in certain positions and more. Usually, this series of physical tests will give the spine professional a good idea of the type of back problem the patient has.
· Diagnostic tests. After the physician has a good idea of the source of the patient’s pain, a diagnostic test, such as a CT scan or an MRI scan, is often ordered to confirm the presence of an anatomical lesion in the spine. The tests can give a detailed picture of the location of the herniated disc and impinged nerve roots.
It is important to emphasize that MRI scans and other diagnostic tests are not used to diagnose the patient’s pain; rather, they are only used to confirm the presence of an anatomical problem that was identified or suspected through the medical history and physical exam. For this reason, while the radiographic findings on an MRI scan or other tests are important, they are not as significant in diagnosing the cause of the patient’s pain (the clinical diagnosis) as are the findings from the medical history and physical exam. Often, an MRI scan or other type of test will be used mainly for the purpose of surgical planning—for example, so the surgeon can see exactly where the herniated disc is and how it is impinging on the nerve root.
What happens when a disc herniates:
While the spinal discs are designed to withstand significant amounts of force, injury and other problems with the disc can occur. When the disc ages or is injured, the outer portion (annulus fibrosus) of a disc may be torn and the disc’s inner material (nucleus pulposus) can herniate or extrude out of the disc. Each spinal disc is surrounded by highly sensitive nerves, and the inner portion of the disc that leaks out contains inflammatory proteins, so when this material comes in contact with a nerve it can cause pain that can travel down the length of the nerve. Even a small disc herniation that allows a small amount of the inner disc material to just touch the nerve can cause significant pain.
Pain from a herniated disc vs. degenerative disc disease:
A herniated disc will typically produce a different type of pain than degenerative disc disease (another common disc problem).
· When a patient has a symptomatic degenerated disc (one that causes pain or other symptoms), it is the disc space itself that is painful and is the source of pain. This type of pain is typically called axial pain.
· When a patient has a symptomatic herniated disc, it is not the disc space itself that hurts, but rather the disc problem is causing pain in a nerve in the spine. This type of pain is typically called radicular pain (nerve root pain, or sciatica from a lumbar herniated disc).
Typical symptoms of a herniated disc:
A herniated disc most often occurs in the lumbar spine (lower back) or the cervical spine (neck), but it can also occur in the thoracic spine (upper back). Each location for a herniated disc produces different symptoms of pain.
Lumbar herniated disc:
Leg pain (also known as sciatica) is the most common symptom associated with a herniated disc in the lumbar spine. Approximately 90% of herniated discs occur at L4-L5 and L5-S1, causing pain in the L5 or S1 nerve that radiates down the sciatic nerve. Symptoms of a herniated disc at these locations are described below:
· A herniated disc at lumbar segment 4 and 5 (L4-L5) usually causes L5 nerve impingement. In addition to sciatica pain, this type of herniated disc can lead to weakness when raising the big toe and possibly in the ankle, also known as foot drop. Numbness and pain can also be felt on top of the foot.
· A herniated disc at lumbar segment 5 and sacral segment 1 (L5-S1) usually causes S1 nerve impingement. In addition to sciatica, this type of herniated disc can lead to weakness when standing on the toes. Numbness and pain can radiate down into the sole of the foot and the outside of the foot.
Cervical herniated disc:
A cervical herniated disc is less common than a lumbar herniated disc because there is less disc material and substantially less force across the cervical spine. The pain and other symptoms from a cervical herniated disc differ by level:
· A herniated disc at cervical segment 4 and 5 (C4-C5) causes C5 nerve root impingement. Patients may feel weakness in the deltoid muscle in the upper arm but do not usually feel numbness or tingling sensations. A cervical herniated disc at this level can also cause shoulder pain.
· A herniated disc at cervical segment 5 and 6 (C5-C6) causes C6 nerve root impingement. This level is one of the most common areas for a cervical herniated disc to occur. It can cause weakness in the biceps (the muscles in the front of the upper arms) and in the wrist extensor muscles. Pain, numbness and tingling can radiate to the thumb side of the hand.
· A herniated disc at cervical segment 6 and 7 (C6-C7) causes C7 nerve root impingement and is another common type of cervical herniated disc. It can cause weakness in the triceps (the muscles in the back of the upper arm and extending to the forearm) and in the extensor muscles of the fingers. Numbness and tingling along with pain can radiate down the triceps and into the middle finger.
· A herniated disc at cervical segment 7 and thoracic segment 1 (C7-T1) causes C8 nerve root impingement. This may lead to weakness when gripping with the hand, along with numbness, pain, and tingling that radiates down the arm and to the little finger side of the hand.
Thoracic herniated disc:
Herniated discs in the upper back are rarely symptomatic and rarely produce pain, but if they are symptomatic, the pain is usually felt in the upper back and/or chest area.
Diagnosis of a herniated disc guides treatment:
Obtaining correct clinical diagnosis is crucial, as the choice of treatment options will be guided by the diagnosis. Patients are well advised to never accept a diagnosis based solely on findings from an MRI scan or other radiographic test. Instead, an accurate clinical diagnosis must be based primarily on the patient’s symptoms and other information from the patient’s medical history as well as a thorough physical exam from a spine care professional.
Treatment options for a herniated disc
Individualized treatment for a herniated disc
The primary goal of treatment for each patient is to help relieve pain and other symptoms resulting from the herniated disc. To achieve this goal, each patient’s treatment plan should be individualized based on the source of the pain, the severity of pain and the specific symptoms that the patient exhibits.
In general, patients usually are advised to start with a course of conservative care (non-surgical) prior to considering spine surgery for a herniated disc. Whereas this is true in general, for some patients early surgical intervention is beneficial. For example, when a patient has progressive major weakness in the arms or legs due to nerve root pinching from a herniated disc, having surgery sooner can stop any neurological progression and create an optimal healing environment for the nerve to recover. In such cases, without surgical intervention, nerve loss can occur and the damage may be permanent.
There are also a few relatively rare conditions that require immediate surgical intervention. For example, cauda equina syndrome, which is usually marked by progressive weakness in the legs and/or sudden bowel or bladder dysfunction, requires prompt medical care and surgery.
Conservative and surgical treatments
For lumbar and cervical herniated discs, conservative (non-surgical) treatments can usually be applied for around four to six weeks to help reduce pain and discomfort. A process of trial and error is often necessary to find the right combination of treatments. Patients may try one treatment at a time or may find it helpful to use a combination of treatment options at once. For example, treatments focused on pain relief (such as medications) may help patients better tolerate other treatments (such as manipulation or physical therapy). In addition to helping with recovery, physical therapy is often used to educate patients on good body mechanics (such as proper lifting technique) which helps to prevent excessive wear and tear on the discs.
If conservative treatments are successful in reducing pain and discomfort, the patient may choose to continue with them. For those patients who experience severe pain and a high loss of function and don’t find relief from conservative treatments, surgery may be considered as an option.
The different conservative and surgical treatment options for a lumbar herniated disc and a cervical herniated disc are described below.
Lumbar herniated disc treatments
Conservative treatments for a lumbar herniated disc
A combination of the following conservative treatment options can be used through at least the first six weeks of discomfort and pain:
· Physical therapy, exercise and gentle stretching to help relieve pressure on the nerve root
· Ice and heat therapy for pain relief
· Manipulation (such as chiropractic manipulation)
· Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, naproxen or COX-2 inhibitors for pain relief
· Narcotic pain medications for pain relief
· Oral steroids to decrease inflammation for pain relief
· Epidural injections to decrease inflammation for pain relief
Surgical treatments for a lumbar herniated disc
If a course of conservative treatments (generally four to six weeks) is not effective for relieving pain from a herniated disc, lumbar decompression surgery may be considered as an option. Often a microdiscectomy (or microdecompression) - a type of lumbar decompression surgery - is used to treat nerve compression from a herniated disc. During a minimally-invasive microdiscectomy procedure, the herniated portion of the disc under the nerve root is removed. By giving the nerve root more space, pressure is relieved and the nerve root can begin to heal.
The microdiscectomy procedure is usually highly successful for relieving the leg pain (sciatica) caused by a herniated disc. Although the nerve root takes several weeks or months to fully heal, patients often feel immediate relief of their leg pain and usually have a minimal amount of discomfort following the surgery. For some patients with severe pain and loss of function, having a microdiscectomy surgery early on will be the best treatment for their pain.
Microdiscectomy (microdecompression) spine surgery
In a microdiscectomy or a microdecompression spine surgery, a small portion of the bone over the nerve root and/or disc material from under the nerve root is removed to relieve neural impingement and provide more room for the nerve to heal. A microdiscectomy spine surgery is typically performed for lumbar herniated disc.
Microdiscectomy helps leg pain
A microdiscectomy surgery is actually more effective for treating leg pain (radiculopathy) than for lower back pain. The impingement on the nerve root (compression) can cause substantial leg pain, and while it may take weeks or months for the nerve root to fully heal and any numbness or weakness get better, patients normally feel relief from leg pain almost immediately after a microdiscectomy surgery.
Microdiscectomy spine surgery procedure
A microdiscectomy spine surgery is performed through a small (1 inch to 1 1/2 inch) incision in the midline of the low back.
· First, the back muscles (erector spinae) are lifted off the bony arch (lamina) of the spine. Since these back muscles run vertically, they can be moved out of the way rather than cut (see Figure 1).
· The surgeon is then able to enter the spine by removing a membrane over the nerve roots (ligamentum flavum), and uses either operating glasses (loupes) or an operating microscope to visualize the nerve root.
· Often, a small portion of the inside facet joint is removed both to facilitate access to the nerve root and to relieve pressure over the nerve.
· The nerve root is then gently moved to the side and the disc material is removed from under the nerve root.
· Importantly, since almost all of the joints, ligaments and muscles are left intact, a microdiscectomy spine surgery does not change the mechanical structure of the patient's lower spine (lumbar spine).
When to have microdiscectomy spine surgery
In general, if a patient's leg pain due to a disc herniation is going to get better, it will do so in about six to twelve weeks. As long as the pain is tolerable and the patient can function adequately, it is usually advisable to postpone back surgery for a short period of time to see if the pain will resolve with conservative (non-surgical) treatment alone.
If the leg pain does not get better with conservative treatments, then a microdiscectomy surgery is a reasonable option to relieve pressure on the nerve root and speed the healing. Immediate spine surgery is only necessary in cases of bowel/bladder incontinence (cauda equina syndrome) or progressive neurological deficits. It may also be reasonable to consider back surgery acutely if the leg pain is severe.
Microdiscectomy spine surgery is typically recommended for patients who have experienced leg pain for at least six weeks and have not found sufficient pain relief with conservative treatment (such as oral steroids, NSAID's, and physical therapy). However, after three to six months, the results of the spine surgery are not quite as favorable, so it is not generally advisable to postpone microdiscectomy surgery for a prolonged period of time (more than three to six months).
After the microdiscectomy surgery
Usually, a microdiscectomy spine surgery procedure is performed on an outpatient basis (with no overnight stay in the hospital) or with one overnight in the hospital. Post-operatively, patients may return to a normal level of daily activity quickly.
Some spine surgeons restrict a patient from bending, lifting, or twisting for the first six weeks following surgery. However, since the patient's back is mechanically the same, it is also reasonable to return to a normal level of functioning immediately following microdiscectomy spine surgery. There have been a couple of reports in the medical literature showing that immediate mobilization (return to normal activity) does not lead to an increase in recurrent lumbar herniated disc.
Microdiscectomy spine surgery success rate
The success rate for a microdiscectomy spine surgery is approximately 90% to 95%, although 5% to 10% of patients will develop a recurrent disc herniation at some point in the future.
A recurrent disc herniation may occur directly after back surgery or many years later, although they are most common in the first three months after surgery. If the disc does herniate again, generally a revision microdiscectomy will be just as successful as the first operation. However, after a recurrence, the patient is at higher risk of further recurrences (15 to 20% chance).
For patients with multiple herniated disc recurrences, a spine fusion surgery may be recommended to prevent further recurrences. Removing the entire disc space and fusing the level is the most common way to absolutely assure that no further disc herniations can occur. If the posterior facet joint is not compromised and other criteria are met, an artificial disc replacement may be considered.
Recurrent herniated discs are not thought to be directly related to a patient's activity, and probably have more to do with the fact that within some disc spaces there are multiple fragments of disc that can come out at a later date. Unfortunately, through a posterior microdiscectomy spine surgery approach, only about 5 to 7% of the disc space can be removed and most of the disc space cannot be visualized. Also, the hole in the disc space where the disc herniation occurs (annulotomy) probably never closes because the disc itself does not have a blood supply. Without a blood supply, the area does not heal or scar over. There also is no way to surgically repair the annulus (outer portion of the disc space).
Following a microdiscectomy spine surgery, an exercise program of stretching, strengthening, and aerobic conditioning is recommended to help prevent recurrence of back pain or disc herniation.
Microdiscectomy surgery risks and complications
As with any form of spine surgery, there are several risks and complications that are associated with a microdiscectomy spine surgery procedure, including:
· Dural tear (cerebrospinal fluid leak). This occurs in 1% to 2% of these surgeries, does not change the results of surgery, but post-operatively the patient may be asked to lay recumbent for one to two days to allow the leak to seal.
· Nerve root damage
· Bowel/bladder incontinence
However, the above complications for microdiscectomy spine surgery are quite rare
A more in-depth description of surgery for a lumbar herniated disc can be found in the article Microdiscectomy (microdecompression) spine surgery.
Cervical herniated disc treatments
Conservative treatments for a cervical herniated disc
The first step in conservative treatment is usually rest and the use of non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, naproxen, or COX-2 inhibitors.
If the pain from a cervical herniated disc is severe and/or continues for more than a couple of weeks, physicians may prescribe additional medications including:
· Oral steroids to decrease inflammation and relieve pain
· Oral narcotic agents for severe pain
If the pain lasts for more than two to four weeks, the following conservative treatments are often recommended:
· Physical therapy and exercise to help relieve the pressure on the nerve root
· Low-velocity chiropractic manipulation may be helpful; however, caution should be used with manipulation if the patient is experiencing any neurological deficits
· Manual traction to help open up the cervical foramen where the nerve root exits the spinal canal
· Epidural injections to reduce inflammation and relieve pain
Surgical treatments for a cervical herniated disc
In general, if about six weeks of conservative treatment fails to relieve the arm pain or if the patient and the spine specialist determine that surgical removal of the disc is the best course of treatment, patients may consider anterior cervical decompression (discectomy). During this surgical procedure, the disc material is removed through the front of the neck and then the disc space is usually fused to keep the disc space open. Another surgical option to treat a herniated disc is a posterior cervical laminectomy, where the disc material is removed through the back of the neck.
For a more detailed explanation, please see Anterior cervical decompression (discectomy). Cervical decompression can also be performed through the back of the neck as a posterior cervical decompression (discectomy). For more information, please read Posterior cervical decompression (discectomy).
Conclusion to successful treatment of a herniated disc
Treatment of a herniated disc is complicated because of the individualized nature of each patient’s pain and symptoms. A treatment option that relieves pain and discomfort for one patient may not work for another. However, by working with one or several types of spine specialists, patients can find the best combination of treatment options for their pain and can avoid having surgery too soon or too late.