Disc Herniation

What is Disc Herniation?

A herniated disc is a condition where a substance called nucleus pulposus, which sits between the bones (vertebrae) in your spine, moves out of place. A herniated disc can cause back pain, with sufferers typically recalling a specific event that triggered the pain. This type of pain feels different from usual back pain – it can have a burning or stinging sensation, and may even reach down to the lower body. In severe cases, it could cause muscle weakness or changes in sensation.

These discs in your spine function as a kind of cushion, absorbing shock for the spine. However, when a disc moves out of place or herniates, it may press against a nerve or the spinal cord, causing pain similar to nerve compression or spinal cord dysfunction – a condition called myelopathy. While herniated discs can be very painful, unfortunately, there are limited non-invasive treatments available that significantly alleviate the pain.

Thankfully, painful disc herniations usually improve on their own within a few weeks. Further, some people with herniated discs may not experience any pain. In fact, herniated discs are often seen in people who have no symptoms when they undergo MRI scans. But it’s important to note that if the signs and symptoms of a herniated disc persist for six weeks, imaging tests like MRI scans may be necessary.

In most cases, herniated discs heal without requiring any surgical intervention. However, when the symptoms are not relieved through basic treatments, more aggressive interventions may be required, such as steroid injections into the affected area or surgery. Short term relief can often be achieved through epidural corticosteroid injections. If necessary, surgical removal of the herniated disc, also known as discectomy, has proven to be more effective than only using basic measures up until a year post-surgery.

Healthcare providers need to carefully monitor patients with herniated discs for any serious neurological changes or if their symptoms progress rapidly. These instances may necessitate urgent referral to a neurosurgeon.

What Causes Disc Herniation?

An intervertebral disc is made up of a tough outer ring called the annulus fibrous and a softer inner part called the nucleus pulposus. A disc herniation happens when the nucleus pulposus pushes out through the annulus fibrous. This typically occurs due to aging or wear and tear where the nucleus pulposus loses water and becomes weak, leading to the disc herniation. Trauma, connective tissue disorders, and certain inherited conditions can also lead to disc herniation.

Disc herniation happens most frequently in the lower back or lumbar spine, and then in the neck or cervical spine. The simple reason for this is that these areas endure more physical stress. The mid-back or thoracic spine, on the other hand, has a lesser rate of disc herniation.

Medical experts believe that a herniated disc’s symptoms are due not only to the pressure applied on the nerve by the protruding disc but also the increased local inflammation.

The herniation usually occurs more on the sides where the annulus fibrosus is thin and has less support from the front or back ligaments. A herniation in this area can compress the nerve root, potentially causing pain. If a large disc herniates in the middle, it can press on the spinal cord and lead to spine-related problems. The localized back pain from a herniated disc comes from the pressure it places on the spine’s ligament and from irritation caused by local inflammation.

Risk Factors and Frequency for Disc Herniation

Herniated discs are not uncommon, with around 5 to 20 cases per 1000 adults each year. They are most frequently seen in people aged between 30 to 50 years, with men being twice as likely to have them as women. Only 1 to 3 percent of patients experience symptoms from a herniated disc in the lower spine. This issue is most prevalent among those aged 30 to 50 years. Among people aged 25 to 55, there is a 95 percent chance that herniated discs will occur at either the L4-L5 or L5-S1 level of the spine. However, it’s important to note that disc disease is the cause of back pain in less than 5 percent of patients.

Herniated disc incidence rate is 5 to 20 cases per 1000 adults each year.
Most likely to occur in people aged 30 to 50 years.
Men are twice as likely to experience this condition as women.
Only 1 to 3 percent of patients show symptoms of a herniated disc in the lower spine.
Among people aged 25 to 55, a herniated disc is likely to occur at either L4-L5 or L5-S1.
Disc disease leads to back pain in less than 5% of patients.

Signs and Symptoms of Disc Herniation

Herniated discs are a common issue that happens all along your spine. People usually remember hurting their back by lifting something heavy or twisting in a way that strains their back. This injury often causes pain that feels sharp or burning. The pain can also spread out, often in the path of the nerve that’s being pinched by the herniated disc. Other symptoms can include feeling numb or tingling along the path of the pinched nerve. If the herniation is really severe, people might feel weak or unstable when they walk.

When it comes to the neck part of the spine, the most common problem area is the C6-7 disc. This can cause symptoms that mostly include radiculopathy (nerve root irritation or inflammation). If this is the case, doctors will usually ask about when the symptoms started, where the pain starts and where it spreads to, and if the patient has had any past treatments. During the physical examination, the doctor will check for any weakness or unusual sensations. The doctor will also look for any signs that the spinal cord isn’t working properly. Here are some typical findings:

C5 Nerve – Might cause pain in the neck, shoulder, and scapula (shoulder blade), and numbness on the outside of the arm. Also might cause weakness when you move your shoulder or elbow. Affected reflexes are the biceps and brachioradialis.
C6 Nerve – Might cause pain in the neck, shoulder, scapula, outside of the arm and hand, along with numbness on the outside of the forearm, thumb and index finger. Might cause weakness when you move your shoulder or elbow. Affected reflexes are the biceps and brachioradialis.
C7 Nerve – Could cause pain in the neck, shoulder, middle finger, along with numbness in the index, middle finger, and palm. Might cause weakness in the elbow and wrist. Affected reflex is the triceps.
C8 Nerve – Could cause pain in the neck, shoulder, and inner forearm, with numbness on the inner forearm and hand. Might cause weakness when you extend your fingers, wrist, or thumb. No reflexes are affected.
T1 Nerve – Might cause pain in the neck, inside of the arm, and forearm, whereas numbness is common on the front of the arm and inner forearm. No reflexes are affected.

Next, we have the thoracic spine, which is the middle part of your spine. Disc degeneration here typically causes thoracic discogenic pain syndrome. This usually affects the lower part of the thoracic spine. In three out of four cases, the issue occurs below T8, most commonly T11-T12. Many people with herniated discs here might not have any symptoms and only discover the issue when they get an MRI for another reason. Symptoms for this type of herniation don’t follow a typical pattern and often make it a diagnosis of exclusion.

Finally, in the lumbar spine (your lower back), herniated discs can cause a range of symptoms that only affect certain muscles and skin areas. History here should include when the symptoms started, where the pain starts and where it spreads to, and if the patient has had any past treatments. Again, a thorough neurological exam can help to figure out where the problem is located. Here are some typical findings:

L1 Nerve – Might cause pain and sensory loss in the groin. Hip flexion weakness is rare, and no stretch reflex is affected.
L2-L3-L4 Nerves – Might cause back pain radiating into the front of the thigh and inner lower leg, sensory loss to the front of the thigh and sometimes inner lower leg, hip flexion and adduction weakness, knee extension weakness; decreased patellar reflex.
L5 Nerve – Might cause lower back pain radiating into the buttock, outside of the thigh and calf, and top of the foot and big toe. Sensory loss on the outside of the calf, top of the foot, space between the first and second toe. It could weaken certain movements of the hip, knee, and foot. It might also decrease the semitendinosus/semimembranosus reflex.
S1 Nerve – Might cause lower back pain radiating into the buttock, outside or back of the thigh, back of the calf, outside or bottom of the foot. Could cause sensory loss on the back of the calf, outside, or bottom of the foot. It could cause weakness on hip extension, knee flexion, plantar flexion (pointing your foot), and so on. S2-S4 Nerves – Might cause pain in the sacral or buttock area, which might radiate into the back of the leg or the perineum. Sensory deficit in the medial buttock, perineal, and perianal region.

Last of all is an exam called the straight leg raise test. The person doing this test lays you down on your back and slowly lifts your leg up, keeping your knee straight. They keep lifting your leg more and more to see if it causes your usual pain and numbness. Then, they do the same thing with the leg that’s not causing problems. If this makes the pain and numbness come back, it’s a good sign that you might have a herniated disc.

Testing for Disc Herniation

For over 85% of people with symptoms thought to be from a slipped (herniated) spinal disc, these symptoms will usually improve over a period of 8 to 12 weeks without needing any specific treatment. However, individuals who show abnormal results during a neurological exam or do not respond to simple pain relief measures may need more in-depth investigation and treatment.

There are different types of imaging techniques to investigate this issue further. X-rays are widely available in many healthcare facilities and can be used to check for any issues with the structure of the spine. If an x-ray reveals a fracture, further investigation using a computed tomography (CT) scan or magnetic resonance imaging (MRI) is required.

A CT scan is often the go-to method for visualizing the bones of the spine and can also reveal calcified slipped discs. While not as easily accessible as x-rays, CT scans are generally more convenient than MRIs. For patients who cannot undergo an MRI scan due to certain medical devices inside their body, a specialized type of CT scan known as myelography can be used to visualize the slipped disc.

An MRI is considered the best and most sensitive method for visualizing a slipped disc. The detailed images provided by an MRI can help surgeons and other healthcare providers plan the best course of treatment if this is needed.

Treatment Options for Disc Herniation

If you have a herniated disc in your neck or back, your doctor will usually recommend non-surgical treatments first. Anti-inflammatory medications and physical therapy are among the top recommended strategies. However, it’s important to note that physical therapy is usually not advised when the symptoms first appear. Since many disc herniation cases improve within a few weeks, doctors prefer to wait for about three weeks before starting physical therapy. Both these methods can effectively manage pain caused by the condition.

For those who don’t respond to this conservative approach, or who experience loss of nerve function, a consultation with a surgeon might be necessary. As for muscle relaxants like cyclobenzaprine or oral steroids, there isn’t a lot of evidence supporting their use for this condition. In cases where the pain is extreme and over-the-counter painkillers don’t help, a doctor may prescribe opioid pain relief medicines. However, this should always be done after a discussion about the risks, benefits, and potential side effects, and for the shortest time possible.

If pain is not managed with initial treatments and continues for four to six weeks, injection treatments targeting the spine or affected nerve root might be considered. Evidence on the long-term effectiveness of these injections is limited, but it’s not uncommon for them to be repeated if they provide relief.

If non-surgical treatments aren’t working, surgery may be considered as a last resort. Surgical options include removal of part of the bone to ease pressure on the nerves (laminectomies) along with removing the herniated disc material (discectomies). This can be done from the front or back of the spine, with options for fusion or artificial disk replacement depending on the case. Surgery for herniated discs in the lower spine may involve a side or front approach, with complete discectomy and fusion. It’s worth noting that while surgery may provide moderate benefits, these often decrease over time after the procedure.

When a doctor is trying to diagnose a herniated disc, they also consider other conditions that can cause similar symptoms. These could include:

A discal cyst (a fluid-filled sac near the spinal disc)
Mechanical back pain (caused by strain, overuse, or injury)
Degenerative spinal stenosis (narrowing of the spaces in the spine)
Epidural abscess (a collection of pus near the spine)
Epidural hematoma (a collection of blood in the space outside the brain)
Metastasis (spread of cancer to the spine)
Diabetic amyotrophy (nerve damage due to diabetes)
Neurinoma (a nerve tissue tumor)
Osteophytes (bony projections along the edges of bones)
Cauda equina syndrome (a rare disorder affecting the bundle of nerve roots at the lower end of the spinal cord)
Synovial cyst (a fluid-filled sac in the spine)

It’s crucial for the doctor to evaluate all these conditions and perform necessary tests to make the right diagnosis.

What to expect with Disc Herniation

Research shows mixed results when it comes to the prognosis of herniated discs. However, it is generally accepted that most cases respond well to non-surgical treatment. In one study, it was highlighted that about 30% of patients still experienced back pain a year later. Of note, many herniated disc cases show no symptoms and are unintentionally discovered during advanced imaging.

When it comes to symptomatic cases, around 90% of them get better by the sixth week after the injury. While surgery might allow for a faster recovery in those with symptomatic herniated discs, the findings show that the results are pretty much the same as non-surgical treatment a year after the operation.

Possible Complications When Diagnosed with Disc Herniation

Issues related to a herniated disc can include chronic back pain. If a herniated disc isn’t treated, although rare, it can cause long-term nerve damage if the root of the nerve is seriously compressed. Surgery to fix a herniated disc generally works well, but sometimes additional treatments are needed. From an economical viewpoint, symptomatic herniated discs can cause a sizable loss of work and potentially lead to disability. Serious complications from surgery or procedures don’t happen very often, but cases of paralysis and even death have been reported.

Complications:

Chronic back pain
Long-term nerve damage in severe cases
Possibility of additional treatments after initial surgery
Significant loss of work
Potential disability
Rare cases of paralysis and death

Preventing Disc Herniation

When a disc in the upper back, or thoracic spine, slips out of place, it can cause different symptoms based on whether it’s pressing on nerve roots or the spinal cord. People may experience a burning pain, numbness, changes in sensation, and weakness.

Most of the time, these issues get better on their own with time and gentle care. This is also true for slipped discs in the neck, or cervical spine, and lower back, also known as the lumbar spine. People can usually manage their pain at home with over-the-counter medications, heat and ice packs, gentle exercises, and staying as active as comfortable.

The time it takes to recover from a slipped disc can vary. It usually depends on how the injury happened and how severe the slipped disc is. Generally, most people start to recover between two to twelve weeks after the injury.

In many cases, symptoms start to improve within two to three weeks after the injury, so physical therapy usually isn’t recommended until three weeks after symptoms start. Likewise, an MRI scan isn’t usually recommended until at least six weeks after symptoms start, unless the symptoms are particularly severe or are getting rapidly worse.

If someone’s symptoms keep getting worse, or if they don’t respond to typical care methods, then other treatments could be considered. One option is an epidural steroid injection, or using radio waves to lessen the pain. If needed, surgery might be an option to remove the slipped disc and fuse the spine. This is done through an approach that goes through the chest or side of the back.

Frequently asked questions

A disc herniation is a condition where the nucleus pulposus, which is located between the vertebrae in the spine, moves out of place. This can cause back pain and other symptoms such as muscle weakness or changes in sensation. In severe cases, it may press against a nerve or the spinal cord, causing pain similar to nerve compression or spinal cord dysfunction.

Herniated disc incidence rate is 5 to 20 cases per 1000 adults each year.

Signs and symptoms of disc herniation can vary depending on the location of the herniated disc along the spine. Here are the typical signs and symptoms associated with disc herniation in different areas of the spine: 1. Neck (Cervical spine): - C5 Nerve: Pain in the neck, shoulder, and shoulder blade, numbness on the outside of the arm, weakness when moving the shoulder or elbow. - C6 Nerve: Pain in the neck, shoulder, shoulder blade, arm, and hand, numbness on the outside of the forearm, thumb, and index finger, weakness when moving the shoulder or elbow. - C7 Nerve: Pain in the neck, shoulder, middle finger, numbness in the index finger, middle finger, and palm, weakness in the elbow and wrist. - C8 Nerve: Pain in the neck, shoulder, inner forearm, numbness on the inner forearm and hand, weakness when extending fingers, wrist, or thumb. - T1 Nerve: Pain in the neck, inner arm, and forearm, numbness on the front of the arm and inner forearm. 2. Thoracic spine: - Thoracic discogenic pain syndrome: Lower thoracic spine disc degeneration causing pain, usually below T8, most commonly T11-T12. Symptoms don't follow a typical pattern and may require exclusion diagnosis. 3. Lower back (Lumbar spine): - L1 Nerve: Pain and sensory loss in the groin, rare hip flexion weakness, no affected stretch reflex. - L2-L3-L4 Nerves: Back pain radiating into the front of the thigh and inner lower leg, sensory loss to the front of the thigh and sometimes inner lower leg, hip flexion and adduction weakness, knee extension weakness, decreased patellar reflex. - L5 Nerve: Lower back pain radiating into the buttock, thigh, calf, and top of the foot and big toe, sensory loss on the outside of the calf, top of the foot, and space between the first and second toe, weakness in certain hip, knee, and foot movements, decreased semitendinosus/semimembranosus reflex. - S1 Nerve: Lower back pain radiating into the buttock, thigh, calf, and bottom of the foot, sensory loss on the back of the calf, outside, or bottom of the foot, weakness in hip extension, knee flexion, plantar flexion, and more. - S2-S4 Nerves: Pain in the sacral or buttock area, radiating into the back of the leg or perineum, sensory deficit in the medial buttock, perineal, and perianal region. In addition, the straight leg raise test is an exam that can help diagnose disc herniation. It involves lifting the leg while keeping the knee straight to see if it causes pain and numbness. If the pain and numbness are reproduced, it suggests a possible herniated disc.

A disc herniation occurs when the nucleus pulposus pushes out through the annulus fibrous of an intervertebral disc. This can happen due to aging, wear and tear, trauma, connective tissue disorders, certain inherited conditions, or a combination of these factors.

A doctor needs to rule out the following conditions when diagnosing Disc Herniation: - A discal cyst (a fluid-filled sac near the spinal disc) - Mechanical back pain (caused by strain, overuse, or injury) - Degenerative spinal stenosis (narrowing of the spaces in the spine) - Epidural abscess (a collection of pus near the spine) - Epidural hematoma (a collection of blood in the space outside the brain) - Metastasis (spread of cancer to the spine) - Diabetic amyotrophy (nerve damage due to diabetes) - Neurinoma (a nerve tissue tumor) - Osteophytes (bony projections along the edges of bones) - Cauda equina syndrome (a rare disorder affecting the bundle of nerve roots at the lower end of the spinal cord) - Synovial cyst (a fluid-filled sac in the spine)

The types of tests that may be needed for disc herniation include: - X-rays: to check for any issues with the structure of the spine and to look for fractures. - CT scan: to visualize the bones of the spine and reveal calcified slipped discs. - MRI: considered the best and most sensitive method for visualizing a slipped disc and providing detailed images for treatment planning. - Myelography: a specialized type of CT scan that can be used to visualize the slipped disc in patients who cannot undergo an MRI scan due to certain medical devices inside their body. These tests can help doctors diagnose and determine the best course of treatment for disc herniation.

Disc herniation is typically treated with non-surgical methods as the first line of treatment. This includes the use of anti-inflammatory medications and physical therapy. However, physical therapy is usually not recommended when symptoms first appear, and doctors prefer to wait for about three weeks before starting it. If conservative treatments do not work or if there is a loss of nerve function, a consultation with a surgeon may be necessary. In some cases, injection treatments targeting the spine or affected nerve root may be considered. Surgery is considered a last resort and may involve removing part of the bone and the herniated disc material, with options for fusion or artificial disk replacement depending on the case.

The prognosis for disc herniation is generally good, with most cases responding well to non-surgical treatment. Around 90% of symptomatic cases improve by the sixth week after the injury. While surgery may lead to a faster recovery, the results are similar to non-surgical treatment a year after the operation. However, about 30% of patients may still experience back pain a year later.

A neurosurgeon.