Lumbar Disc Herniation: Frequently Asked Questions

A spinal disc is a soft, rubbery structure located between the vertebral bodies (bones of the spine). The disc acts as a pad or cushion for the bone. The outer portion of the disc (the annulus fibrosus) is made up of a tough fibrocartilage.

The middle section (the nucleus pulposus) is composed of water and collagen and has a gelatinous consistency. (Some people describe the disc structure as resembling a jelly donut.) The disc allows for movement of the vertebral bodies and provides a buffer for compression between the bones.

In a healthy disc, this system works very well. But degeneration of or injuries to the disc can lead to a lumbar disc herniation.

Overhead illustration of a lumbar spinal disc

• What is a lumbar disc herniation?
• What is a disc protrusion versus an extrusion?
• What are the symptoms of lumbar disc herniation?




• Why do I feel pain in my leg if the herniated disc is in my back?
• What is the treatment for lumbar disc herniation?




• When is surgery needed for lumbar disc herniation?
• What is the surgery for a lumbar herniated disc?
• What happens to my herniated disc if I don’t have surgery?

What is a lumbar disc herniation?

A herniated lumbar disc is a broad term to describe a change in a spinal disc of the lower back. A disc herniates when there is tear in its tough, outer, fibrocartilaginous layer (called the annulus fibrosus), allowing portions of its gelatinous, inner layer, the nucleus pulposus, to leak out through the tear. There are several different types of disc herniations. Herniations can be protrusions, extrusions, or sequestrations.

Overhead (top view) illustration of a lumbar vertebra with a herniated disc

What is a disc protrusion versus an extrusion?

There are different types of disc herniations, and they are described according to their size and how they look. Remember, a spinal disc rests between two vertebral bodies of bone and there is often a lot of pressure between these structures. A disc bulge is a normal age-related change to the disc where the outer part of the disc flattens. A disc protrusion is a type of disc herniation where the depth of the herniated disc material is shorter than how broad it is. A disc extrusion is where the depth of the herniated disc material is larger than how broad it is. A disc sequestration is where the herniated fragment or material is no longer connected with the disc.

What are the symptoms of lumbar disc herniation?

In some cases, herniations cause no symptoms whatsoever. When symptoms occur, the most common symptom from a lumbar disc herniation is lower back pain. If the disc herniation causes impingement of a nerve, for example, one of the nerves that make up the sciatic nerve, pain may also radiate down into the leg via the sciatic nerve (a condition known as sciatica). In addition to leg pain, the leg may also be weak or numb.

Overall, whenever a disc has herniated, it can cause various pain symptoms and additional, related conditions.

• The disc may become painful itself.
• It may irritate a nerve exiting the spinal column, leading to pain, weakness, numbness or tingling in the leg.
• It may even contribute to a narrowing of the spinal canal itself, also known as lumbar spinal stenosis, which often leads to pain, weakness, numbness or tingling in the leg.

What does it mean that my MRI report says I have multiple herniated discs?

What you feel in terms of pain or discomfort is more important than what the MRI report says, because it is quite common for spinal imaging to reveal that a person has multiple herniated spinal discs, even if they are experiencing no back pain. Therefore, the most important thing is not the MRI report itself, but rather correlating your symptoms and physical exam with the MRI report. If the MRI report indicates that a disc herniation is present, this could be significant or insignificant, depending on your symptoms and other factors.

Why do I feel pain in my leg if the herniated disc is in my back?

The lumbar disc sits between two vertebral bodies. Behind the vertebral bodies and discs lie the spinal cord and nerves. The nerves in your legs originate from the spinal cord and its nerve roots. The nerves run in the central spinal canal and then come out between two of the spinal vertebrae in a space called the foramen. When a disc herniates, it can impinge a nerve where it comes down in the central canal or where it comes out in the foramen which can then send pain down the leg.

When these nerves are still in the spinal canal, they are named in reference to the disc level they are located near. For instance, the L5 nerve comes down in the central canal at the L4-5 and above levels and then comes out in the foramen at the disc level between the L5 and S1 vertebral bodies. (S1 is the first vertebra of the sacral spine.) Once they exit the canal at the individual vertebrae levels, the nerves come together to make up named nerves, such as the sciatic nerve, which is made up of the L4, L5, S1, S2 and S3 nerves. Therefore, if any of these nerves are impinged up near the spinal column, patients can feel pain where the sciatic nerve is in the leg (a condition known as sciatica).

Illustration of a herniated disc causing sciatica.

What is the treatment for lumbar disc herniation?

There are a lot of options for treatment of a herniated disc in the lower back before considering surgery, including weight loss, a physical therapy program that may include recommendations for activity modification, pain medications, and/or epidural steroid injections.

Weight loss can help alleviate added pressure on the lower back and decrease the overall inflammation in a patient’s body, while a well-directed physical therapy program will allow for the disc to heal and provide improvements in biomechanics and strength. Pain medications can often be helpful. For instance, anti-inflammatory medications can be helpful to decrease the inflammation and muscle relaxers can be helpful to decrease the muscle spasms that occur as a result of a disc herniation. Often, physical therapy, with or without the benefit of pain medications, can allow a patient to feel better, improving a patient’s pain and functionality.

However, when the pain becomes too severe, specifically nerve pain felt in the leg from the disc herniation, and does not respond to physical therapy and medications, epidural steroid injections can be very helpful. Studies have shown excellent pain reduction and improvement in function with the use of epidural injections. Although epidural injections are safer than more invasive surgical procedures, there can be complications. These include new pain, worsening pain, bleeding, headaches, adverse reaction to the medication injected or, even more rarely, infections, or injury to a nerve.

For many patients, a combination of treatment options including medications, physical therapy, and epidural injections results in the best outcomes. (Find a doctor who treats herniated discs.)

What should I do if a herniated disc still hurts after a year?

Most herniated discs will resolve on their own, or their associated symptoms will be alleviated with conservative treatments. If the patient’s functionality is greatly impacted and they have not responded to activity modification and other conservative measures, it is reasonable to consult with a surgeon about spine surgery options.

Many times, symptoms from a disc herniation will be very short-lived and quickly resolve. However, symptoms from herniated discs can linger because we use our spine to differing extents with differing loads on the spine with everything we do throughout our day.

An analogy to consider is a scratch on the arm. With a scratch on the arm, a patient often bandages it and leaves it alone and, because of this, after a few days the scratch heals and sometimes scars. When a disc tears and herniates, the body tries to heal the disc, but we have to use our spine with everything we do throughout our day. Therefore, the healing process can become prolonged as the scab may at times be ripped open, and new tears can occur. Therefore, learning how to bend, lift and twist in the most optimal way for our spine is of utmost importance to help prevent reinjury.

Whether the disc is symptomatic for one day or one year, the conservative approach is the same as long as there is not progressive neurologic change. Activity modification is required so the disc is not reinjured and therapeutic exercise in the form of physical therapy is beneficial to work on strengthening around the spine and stability. Medications can be considered along with epidural injections if there is nerve pain secondary to the disc herniation.

Can a herniated disc heal after two years?

A herniated disc can at times “resorb” – where the body’s own cells come in and get rid of the damaged disc material. Regardless of whether  the disc material that has herniated becomes resorbed, the tear in the outer portion of the disc can scar over and the herniated material can be contained in such a way that, over time, it ceases to cause pain, weakness, numbness or tingling. This healing process is facilitated by modifying movement and activity to use optimal mechanics for the spine – which is hopefully a part of any physical therapy program. Using the “scratch on the arm” analogy previously mentioned, if the scratch and scar are not repeatedly injured and irritated, then the disc can heal appropriately.

When is surgery needed for lumbar disc herniation?

There are some situations where surgery is probably the best solution. These include if you have cauda equina syndrome, progressive strength loss, intractable pain, or other continued symptoms despite trying nonsurgical treatments.

Cauda equina syndrome

Cauda equina syndrome is an extremely rare but serious disorder affecting a bundle of spinal nerve roots, and it requires urgent surgery. This syndrome involves back and leg pain, weakness and numbness, and may be associated with problems with bladder and bowel function. This condition usually arises only in the case of a severe lumbar disc herniation that severely decreases the space where the spinal nerves come down in the central canal.

Progressive strength loss

There are times when strength loss is noticed. However, if the patient has new or progressive weakness, this would be an indication for surgery.

Intractable pain and failure of conservative care

If pain cannot be controlled with medicines, injections, or physical therapy, or if a comprehensive program including all of these options has failed, you may be a candidate for surgery.

What is the surgery for a lumbar herniated disc?

Whether there is one or multiple herniated discs, various types of spinal decompression and spinal fusion surgeries are available to treat lumbar disc herniations. These include microdiscectomy, lumbar laminectomy or a lumbar interbody fusion. The choice of which procedure is appropriate depends on the condition and other factors in each individual patient. In some people who have an isolated disc herniation, a disc replacement surgery may be a viable alternative to fusion. Where possible, a minimally invasive approach is often preferred. Ultimately, the surgeon indicates and decides on the best surgical option with the patient’s safety and goals as the utmost priority in the decision-making process.

What happens to my herniated disc if I don’t have surgery?

A study of patients with different sized herniations showed that by six months to one year, herniated disc material had resorbed in many of the cases. The larger the herniation (extrusions), the faster the material was resorbed. Long-term studies have shown that, although surgical intervention may generate a faster initial recovery time, conservative (nonsurgical) outcomes are equally effective in patients after five and 10 years.

However, if progressive neurologic changes are occurring, it is advised to consult with both a non-operative spine specialist and with a surgeon, who may best determine together the best path forward. For instance, weakness can improve on its own, however, the longer you wait to intervene from a surgical standpoint, the less likely it is that neurologic recovery will be seen. Furthermore, cauda equina syndrome is a surgical emergency to prevent loss of bladder and bowel function along with worsening weakness, numbness and tingling.

References

Updated: 3/17/2023

Authors

Andrew Paul Creighton, DO

Assistant Attending Physiatrist, Hospital for Special Surgery
Assistant Professor, Clinical Rehabilitation Medicine, Weill Cornell Medical College

Related articles

References

• Birkmeyer NJ, Weinstein JN: Medical versus surgical treatment for low back pain: evidence and clinical practice. Eff Clin Pract. 1999 Sep-Oct;25:218-27.
• Boden SD, Davis DO, Dina TS, Patronas NJ, Wiesel SW: Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. A prospective investigation. J Bone Joint Surg Am. 1990 Mar;723:403-8.
• Brant-Zawadzki MN, Jensen MC, Obuchowski N, Ross JS, Modic MT: Interobserver and intraobserver variability in interpretation of lumbar disc abnormalities. A comparison of two nomenclatures. Spine. 1995 Jun 1;2011:1257-63; discussion 1264.
• Fritz, Julie M. PhD, PT, ATC *; Delitto, Anthony PhD, PT, FAPTA *+; Erhard, Richard E. DC, PT: Comparison of Classification-Based Physical Therapy With Therapy Based on Clinical Practice Guidelines for Patients with Acute Low Back Pain: A Randomized Clinical Trial. Spine. 2813:1363-1371, July 1, 2003.
• Huston CW, Slipman CW, Garvin C: Complications and side effects of cervical and lumbosacral selective nerve root injections. Arch Phys Med Rehabil. 2005 Feb;862:277-83.
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• Spencer DL: The anatomical basis of sciatica secondary to herniated lumbar disc: a review. Neurol Res. 1999;21 Suppl 1:S33-6. Review.
• Vad, Vijay B. MD; Bhat, Atul L. MD ,[S]; Lutz, Gregory E. MD; Cammisa, Frank MD:Transforaminal Epidural Steroid Injections in Lumbosacral Radiculopathy: A Prospective Randomized Study. Spine. 271:11-15, January 1, 2002.
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Disc Disorder Success Stories

Epidural injections for the treatment of symptomatic lumbar herniated discs

Clinical Trial

. 2002 Aug;15(4):269-72.

doi: 10.1097/00024720-200208000-00001.

Jeffrey C Wang 
¹
, Eric Lin, Darrel S Brodke, Jim A Youssef

Affiliations

Affiliation

• ¹ UCLA Department of Orthopaedic Surgery, UCLA School of Medicine, Los Angeles, California 90095-6902, USA.

• PMID:

  12177540

• DOI:

  10.1097/00024720-200208000-00001

Clinical Trial

Jeffrey C Wang et al.

J Spinal Disord Tech.

2002 Aug.

. 2002 Aug;15(4):269-72.

doi: 10.1097/00024720-200208000-00001.

Authors

Jeffrey C Wang 
¹
, Eric Lin, Darrel S Brodke, Jim A Youssef

Affiliation

• ¹ UCLA Department of Orthopaedic Surgery, UCLA School of Medicine, Los Angeles, California 90095-6902, USA.

• PMID:

  12177540

• DOI:

  10.1097/00024720-200208000-00001

Abstract

Epidural steroid injections are widely used as part of the conservative care for symptomatic herniated lumbar discs. There are studies showing their effectiveness, and some studies demonstrating no clinical benefits. The purpose of this study was to evaluate the effectiveness of epidural steroid injections for patients with symptomatic lumbar disc herniations who were surgical candidates. Sixty-nine patients were diagnosed with a herniated disc in the lumbar spine and remained symptomatic despite conservative care, and were treated with an epidural injection in an attempt to avoid surgical discectomy. Of the total group of 69 patients (average age = 44.8 years, range 19-77 years, average follow-up = 1.5 years), 53 (77%) had successful resolution or significant decrease of their symptoms and were able to avoid surgery. Only 16 (23%) patients failed to have significant relief of their symptoms and required surgical treatment of their herniated disc. Epidural steroid injections have a reasonable success rate for the alleviation of radicular symptoms from lumbar herniated discs for up to twelve to twenty-seven months. Patients treated with injections may be able to avoid surgical treatment up to this period and perhaps even longer.

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Sequestered disc herniation – treatment, symptoms, causes, diagnosis

Video

Title

• Symptoms
• Diagnostics
• Methods of treatment

Sequestered disc herniation (herniated disc with sequestration) is the most severe degree of disc disruption in which the substance of the disc nucleus falls out and completely separates from the disc. A herniated intervertebral disc, which performs a shock-absorbing function, is a rupture of the fibrous ring of the disc and a bulging of the nucleus pulposus. The symptoms of a ruptured disc can vary depending on the severity of the rupture and the location of the ruptured disc.

Disc herniations are classified based on the degree of tear and location in relation to the posterior longitudinal ligament. The posterior longitudinal ligament runs vertically along the spine and runs near each disc along the back. The posterior longitudinal ligament separates the posterior part of the disc from the epidural space that surrounds some of the spinal nerve roots. Violation of the integrity of the fibrous ring is divided into protrusion, extrusion and sequestration.

Protrusion protrusion of the annulus fibrosus occurs, but without damage and impact on the longitudinal ligament and preservation of the nucleus pulposus within the annulus fibrosus. Protrusion may be painless or accompanied by pain, depending on the effect on the nerves. Disk extrusion (disc herniation) is a complete rupture of the anulus fibrosus, which allows the substance of the nucleus pulposus to seep into the epidural space. Symptoms of disc extrusion also depend on the effect on the nerve structures.

Disc sequestration means that the nucleus pulposus has fallen out of the disc in its entirety and separated from the disc due to contact with the longitudinal ligament. Material from the nucleus pulposus may enter the epidural space and is considered a loose fragment. Disc sequestration is often accompanied by severe pain in the back and legs. In severe cases, the patient may develop cauda equina syndrome, which is manifested by a violation of the activity of the bladder and intestines and a violation of sensitivity in the lower extremities. Cauda equina syndrome is an indication for emergency surgical treatment, since without surgery there may be irreversible damage to the nerve structures. In most cases, sequestration of disc herniation occurs against the background of pronounced degenerative changes in the intervertebral discs. But sequestration of disc herniation can occur both from systematic intensive loads, and from excessive one-time loads. Although most patients with a herniated disc do not need surgery, sequestered disc herniation greatly increases the likelihood of surgery, especially in cases where there are severe neurological symptoms.

Symptoms

A herniated disc does not always cause pain or neurological symptoms and is often asymptomatic. Therefore, in itself, the detection of a herniated disc, for example, during an MRI examination, is not proof of the existing symptoms. Symptoms associated with a herniated disc (including sequestered ) will depend on the age of the patient, the location of the herniated disc, and the location of the sequester . As a rule, with sequestration of a herniated disc in the lumbar spine, pain will be in the lower back radiating to the legs, numbness, tingling and / or weakness in the lower extremities is also possible. At first, only the presence of local pain in the lower back is possible. Later, the pain begins to radiate to the buttock, thigh, and foot. Leg pain can be sharp, stabbing, and start suddenly. In patients with a disc herniation in the lumbar region, the pain syndrome may increase when sitting, there is pain when bending over, antalgic scoliosis is possible due to muscle spasm on one side. The most frequent complaints of patients with sequestered disc herniation is the inability to drive a car for a long time or the inability to put on socks in the morning. Serious symptoms that require emergency surgery are the symptoms of cauda equina syndrome.

Diagnosis

Physician based on medical history, patient complaints, and neurological examination (deep tendon reflexes, muscle testing, sensitivity testing ) can make a preliminary diagnosis. Neurological examination reveals sensory disturbances, decreased muscle strength, decreased or absent deep tendon reflexes. If the necessary data are available, the doctor may prescribe instrumental research methods.

Radiography allows to detect structural changes in the bone tissue structures of the spine, but this research method is not very informative in diagnosing herniated discs.

The most informative in terms of diagnosing herniated discs (including those with sequestration) is an MRI study, which allows not only visualizing a herniated disc, but also detecting the presence of compression of nerve structures.

ENMG allows you to determine the degree of damage to the nerve fiber and, to a certain extent, predict the effectiveness of treatment.

In some cases, CT or scintigraphy may be necessary for differential diagnosis.

Treatment

Treatment of sequestered disc herniation depends on MRI findings and symptoms. Sequestered hernias mainly occur in the lumbar and cervical spine. Conservative treatment for sequestered disc herniations is possible (physiotherapy, drug treatment, acupuncture), but it must be borne in mind that conservative treatment is not always effective.

Drug treatment includes the use of NSAIDs, muscle relaxants. It is also possible to inject corticosteroids in combination with anesthetics into the damaged area. Anesthetics immediately relieve pain, and steroids reduce inflammation associated with the irritating effect of substances in the nucleus pulposus on surrounding tissues. Physiotherapy is also widely used in the treatment of herniated discs with sequestration, allowing to reduce swelling, inflammation and thus reduce pain.

Acupuncture helps to improve the conduction of impulses along nerve fibers, relieve pain.

But often the methods of conservative treatment for sequestered disc herniation are not effective, and surgical treatment is required.

Modern technologies using endoscopic techniques allow operative decompression to be performed minimally invasively and with little risk of postoperative complications. The most common surgical procedures are discectomy and microdiscectomy. In the presence of instability of the motor segments, spinal fusion (fixation of the vertebrae with each other) can also be performed.

Surgical treatment in 90% of cases can significantly reduce neurological symptoms and restore function. But in some cases, neurological symptoms may persist for a long time after surgery. As a rule, this is possible if the period of compression in the preoperative period was long and led to irreversible changes in the structure of nerve fibers. Therefore, surgical treatment for sequestered hernias should be carried out on time, especially in the presence of persistent severe neurological symptoms. If there are signs of cauda equina, surgery should be performed within 24 hours of the onset of symptoms of cauda equina

Herniated discs

Spinal cord – lumbar disc herniation and other causes of spinal nerve compression. This article presents a systematic approach to patients with spinal nerve root compression in the lumbar region. We will discuss herniated discs, arthrosis of the intervertebral (facet, facet) joints, synovial cysts, spondylolisthesis, and epidural lipomatosis. Images can be enlarged by clicking on them.

The publication is a translation of an article by Robin Smithuis on Radiology Assistant Radiology department of the Rijnland hospital in Leiderdorp, the Netherlands

Systematic approach

Four levels of spinal nerve compression

In patients with symptoms of nerve root compression, the following four levels should be investigated:

1. Disc level
   This is the most common area of ​​nerve compression, mainly due to herniated intervertebral discs, less often due to spinal canal stenosis.
2. Side pocket level.
   This area is below the intervertebral disc where the nerve runs laterally towards the intervertebral foramen. The narrowing of the lateral pocket is caused by arthrosis of the intervertebral joints, usually in combination with hypertrophy of the yellow ligaments and bulging of the intervertebral disc.
3. Foraminal zone.
   This is the area between the pedicles above and below the underlying vertebrae where the nerve leaves the spinal canal. Narrowing of the intervertebral foramen is caused by arthrosis of the intervertebral joints, spondylolisthesis and foraminal disc herniation – usually with disc migration from a lower level.
4. Extraforaminal area.
   The area outside the intervertebral foramen. Compression of the spinal nerve in this area is rare, but can sometimes be caused by lateral hernias.

Various pathological processes can be combined at these four levels, for example, a herniated disc can lead to nerve compression not only at the level of the disc, but also at the level of the intervertebral foramen or in the extraforaminal zone, when the disc herniation migrates.

When looking for spinal nerve compression, you should look at all of these levels.

Scroll through the images to follow the nerve path at the level of the disc, lateral pockets, intervertebral foramina and extraforaminal zones.

At each level, there can be both local changes and a combination of pathological processes.
For example, a herniated disc can cause compression of the spinal nerve at the level of the disc, as well as migrate below and compress the nerve in the lateral pocket, or move upward and cause compression in the foraminal or extraforaminal zones.
In patients with arthrosis of the intervertebral joints, bone growths can spread medially and narrow the lateral pocket, and if spreading upwards, narrow the intervertebral foramen.
With severe arthrosis, stenosis of the spinal canal can develop on both sides with compression of all roots at this level.

Anatomy

The image shows the structures surrounding the spinal nerves in the spinal canal.

Yellow bundles
Yellow ligaments – short strong ligaments connecting located on the back surface of the spinal canal and connecting the articular processes of the vertebrae. As a result of arthrosis of the intervertebral joints during aging and instability of the spinal column, the yellow ligaments experience an increased load, which leads to their hypertrophy and fibrosis. The combination of hypertrophy of the yellow ligaments with facet arthrosis leads to narrowing of the lateral pocket, and in the case of a bilateral process, to stenosis of the spinal canal.

Epidural adipose tissue
Adipose tissue surrounds the dural sac containing the spinal nerves. An increase in the amount of epidural fiber can be observed with steroids, excessive obesity, and occasionally idiopathically. An increase in its volume can contribute to the development of spinal stenosis.

MRI protocol

The MRI protocol for suspected spinal nerve compression is quite simple.

We mainly rely on sagittal T1 and T2 images and correlate the found changes with T2 images in the axial plane at levels with signs of pathology.

To image paravertebral soft tissue, do not use saturation bar and rectangular field of view.

Watch for an abdominal aortic aneurysm as it can cause back pain.

It is sometimes difficult to clinically differentiate between neurogenic claudication and vascular claudication due to arterial stenosis.

Partial coding must be done in the anterior-posterior (AP) direction and phase coding from feet to head (feet-head).

This has a number of advantages:

• The spatial resolution is higher in the frequency coding direction. We want to get more resolution in the anterior-posterior direction to look for small hernias and see the roots of the spinal nerves.
• Set frequency encoding direction in AP. If you set the phase encoding direction to AP direction, you will get respiratory artifacts. This is why a saturation band or a rectangular field of view is sometimes used. By using front-to-back for frequency encoding, you avoid these problems without using a saturation band.
• Frequency coding in the head-to-foot direction may result in reduced visualization of the endplate margins of the vertebral bodies due to a chemical shift artifact at the interface between the yellow bone marrow and intervertebral disc water. This is another reason to use leg-to-head phase encoding and front-to-back frequency encoding.

It is useful to position the slices wide at an angle parallel to the level at which compression is suspected. The advantage of this approach is that it is possible to trace the course of the nerve at all four levels of possible compression.

When positioned in several levels at different angles, as in the image on the right, you may not always follow the entire course of the nerve and may not see the full picture.

Interpretation

Sagittal T1 images carry a significant part of the information.
Before looking for a hernia, first take a close look at the prevertebral soft tissue and bone marrow.

After you find any abnormalities, compare them with the changes on the T2 images (see illustration).

Use 3d markers
When you see changes you can help yourself by using 3d markers to match them with changes in other series of images.
If you zoom in, you will see a small yellow cross that points to the point you are looking for on different series – a synovial cyst formed as a result of arthrosis with effusion in the intervertebral joint, which compresses the L5 nerve.

Paravertebral Soft Tissues

The illustration shows images of a 25-year-old patient with low back pain.
Note the multiple small masses in the abdomen surrounding the mesenteric vessels and having a low MR signal intensity corresponding to the intensity of the signal from the bone marrow.
The intensity of the MR signal from the intervertebral disc is slightly higher than the signal from the bone marrow (bright discus sign, a sign of a light disc).

In this example, this is a newly diagnosed colon cancer with bone and lymph node metastases.

This image shows the following patient with massive lymphaadnopathy of the mesenteric retroperitoneal lymph nodes.

Images of a patient with severe lower back pain.
Note the dissection of the aorta.

Sometimes pathological changes in the aorta are incidental findings.

Disc herniation

Disc herniation – disc displacement beyond the boundaries of the intervertebral space.

Hernias are focal (<90º), basal (90º-180º) and protrusion (>180º)

Protrusion : width between the edges of the disc herniation, less than the width at the base of the herniation (read more about the nomenclature in the article Disc protrusion ).

Extrusion : width between the edges of the herniated disc, greater than the width at the base of the herniation (read more about the nomenclature in the article Disc extrusion).

Read Spine – Disc Nomenclature for more information about disc herniation nomenclature.

Focal protrusion at the level of L5/S1 with compression of the S1 spinal nerve (arrow) is shown.

Scroll through and describe the images, then continue reading.

Changes at various levels 1-4:

1. At the level of the intervertebral disc, the minimum narrowing of the spinal canal is determined due to the bulging of the disc and arthrosis of the intervertebral joints.
2. At this level, a significant stenosis is determined due to the bulging of the disc and arthrosis of the intervertebral joints. The rupture of the fibrous ring is also determined (increased signal), the formation of a disc herniation (yellow arrow).
3. A focal herniated disc with compression of the L5 nerve is visible at the level of the lateral pocket (yellow arrow). Since the distance between the edges of the hernia is greater than the width at the base, this is an extrusion.
4. L5 nerve compression (blue arrow) in side pocket.

The disc herniation has migrated caudally and is seen as a rounded structure anterior to the nerve. The hernia is not limited by anything, that is, it is not covered by the fibers of the annulus fibrosus.

Examine the pictures first.

Image can be enlarged.

Then continue reading.

Findings:

• disc herniation L4/L5
• cranial migration
• compression of the L3 nerve in the intervertebral foramen

Hernias usually have an intermediate T1 MR signal. A high T2 signal indicates a fresh hernia due to a signal from the nucleus pulposus. Low T2 signal intensity indicates an old hernia.

Image shows a disc herniation with increased MR signal (yellow arrow on axial images) propagating through a torn annulus fibers and causing compression of the left L5 nerve (blue arrow).

T1 sagittal images show an area of ​​sharply hypointense MR signal at L4/L5 (arrow) and L5/S1 levels.

Continued below.

T2 images also show a zone of low MR signal intensity.

A CT scan was performed to look for intervertebral disc calcification or other changes.

Continued below.

The low intensity of the MR signal was due to a vacuum phenomenon due to nitrogen-dominated gas in the hernia both at the L4/L5 level (red arrow) and at the L5/S1 level (blue arrow).

Scroll through the presented sagittal T1 images first.

Note changes. Then continue reading.

The most striking change is the zone with an intermediate MR signal corresponding to the signal from the intervertebral disc at this level, posterior to the L3 vertebra (blue arrow).

This is a herniated disc with cranial migration and compression of the L3 nerve on the right.

The image shows the following disk migration example.

Note how the L3/L4 disc herniation migrates caudally along the posterior surface of the L4 vertebral body.

Also note that at the L4-L5 level, the disc component simulates a nerve root (green arrow), while the nerve is compressed and pushed posteriorly and is seen laterally in the intervertebral foramen (yellow arrow).

Lateral pocket stenosis

Lateral pocket stenosis is a common pathology, especially in elderly patients.

As static decreases, instability develops.
This leads to hypertrophy of the intervertebral joints and arthrosis, bulging of the disc and an increase in the load on the yellow ligaments lead to their hypertrophy.
All of these mechanisms lead to stenosis of the lateral pockets (schematic representation).
With advanced arthrosis, synovial cysts can form, leading to an even greater narrowing of the side pockets.

The image shows a patient with bilateral arthrosis of the intervertebral joints leading to narrowing of the lateral pockets with compression of the spinal nerves on both sides.

Synovial cysts

Synovial cysts are often visualized in association with arthrosis of the intervertebral joints. They mainly cause stenosis in the intervertebral joint. With large sizes, they can spread into the intervertebral foramen, causing its stenosis.

The image shows a patient with severe arthrosis of the intervertebral joints.

Note the multiple synovial cysts associated with arthrosis.

At the L5/S1 level, a large cyst compresses the S1 nerve (yellow arrow).

Sagittal T2 images show a patient with a synovial cyst completely filling the intervertebral foramen (arrow).

Note that at first glance the opening appears unchanged, except that the spinal nerve is not visible.
It’s crushed by a cyst.

Axial images of the same patient

Note the dumbbell shape of the synovial cyst at the level of the intervertebral foramen (yellow arrow).

A synovial cyst can be easily missed.

On the presented T2 images, the intervertebral foramen appears unchanged.
Note the absence of the spinal nerve.

In fact, the intervertebral foramen is completely filled with a synovial cyst that compresses and pushes back the spinal nerve root (arrows).

The nerve itself is difficult to distinguish.

Spinal stenosis

Causes of spinal stenosis:

common:

• bilateral arthrosis of the intervertebral joints with protrusion of the intervertebral discs and hypertrophy of the yellow ligaments

less common:

• primary (anatomical, congenital) narrow spinal canal
• spinal injury with epidural hematoma
• tumor or metastatic lesion
• spondylodiscitis with epidural abscess
• spondylolisthesis

Note the narrowing of the spinal canal at several levels, which is better visualized on MR images, but can already be suspected on radiographs, since the pedicles of the vertebrae are very short.

You can zoom in to see this.

On axial T2 images, you can see that there is no cerebrospinal fluid around the spinal nerve roots, which corresponds to severe spinal stenosis, and epidural fat compresses the nerves from behind.

The images show the following example of spinal stenosis.

Once again, radiographs suggest a congenital narrow spinal canal.
Even small disc herniations or bulges in these patients are enough to cause nerve compression.

Axial T2 images show severe spinal stenosis.
Note the short pedicles of the vertebral bodies, combined with arthrosis of the intervertebral joints and hypertrophy of the yellow ligaments.

The images show a patient with multiple vertebral metastases.

At the L1/L2 level, this results in a stenosis with nerve compression (red arrow).

Compression of the spinal nerves at the level of the lumbar spine is not typical of a metastatic lesion.
Much more often, metastases cause compression at the cervical and thoracic levels of the spine, since at these levels the spinal canal has a smaller volume, as well as a smaller amount of cerebrospinal fluid surrounds the spinal cord.

Fractures can cause spinal stenosis, especially when bone fragments are displaced in burst fractures, as well as in fractures with rotation or displacement.

The images show a patient with an old burst fracture.
The bone fragment is displaced posteriorly with the formation of an Urban wedge (red arrow) that compresses the cauda equina.

Epidural lipomatosis

Epidural lipomatosis significant increase in the amount of epidural fatty tissue with compression of the dural sac. The images show a patient with symptoms of spinal stenosis.

The patient is seen to be obese as a result of steroid therapy.

Continued.

Scroll through the images.

Note how the spinal canal is narrowed by epidural tissue. Do not confuse the high intensity of the MR signal from fat with the signal from cerebrospinal fluid.

Stenosis of the intervertebral foramen

Stenosis of the intervertebral foramen is caused by:

• arthrosis of the intervertebral joints
• herniated discs with cranial migration
• spondylolisthesis

Typically, stenosis of the intervertebral foramen is caused by a combination of cranial migration of a herniated disc with arthrosis of the intervertebral joints.
In addition, stenosis is often determined in patients with spondylolisthesis.
Spondylolisthesis is a displacement of the above lying vertebra (usually anteriorly) relative to the lower lying vertebra, more often L4 relative to L5.
Displacement can develop as a result of spondylolysis (stress fracture of the articular process or due to non-fusion of two ossification nuclei) or as a result of arthrosis of the intervertebral joints with displacement of the articular processes.

The images show a patient with severe arthrosis of the L4-L5 intervertebral joint on the right.

Scroll through images of a patient with spondylolisthesis.

Image shows a herniated disc with cranial migration.

Using the cursor allows you to compare changes in T1 and T2 images.

The fact that this is a hernia is better seen on T2 images.
Bottom images with cursor.
You can zoom in to see it.

This foraminal disc herniation is easy to miss.

Notice how slight the changes are on the T2 images.
A herniated disc may be mistaken for a spinal nerve root.

Sagittal T1 images show that this is a herniated disc with cranial migration.

Images show a patient with a combination of spondylolysis (arrow), minimal listhesis, and disc herniation causing compression of the L3 nerve at the foramen magnum.

The images show a patient with severe antelisthesis and bilateral spondylolysis.

Anthelisthesis combined with cranial disc migration causes pronounced narrowing of the intervertebral foramen and compression of the spinal nerves (yellow arrow).

Note the calcification of the upper part of the disc (blue arrow).

Extraforaminal compression

Extraforaminal compression is determined in 5% of cases.
Almost always, lateral disc herniations at the lower levels are the cause of extraforaminal compression.

Images show a patient with a lateral disc herniation causing compression of the overlying nerve and spinal ganglion.