How to Read the MRI for a Herniated Disc and 5 Treatment Options

Magnetic Resonance Imaging (otherwise known as MRI) is one of the most important inventions in modern medicine. With the aid of the MRI, surgeons can accurately evaluate and diagnose conditions that could otherwise be life-altering. MRIs are useful in many aspects of medicine, and especially so in investigating conditions of the spine. 

MRI scans of herniated discs are a helpful test used to determine the exact location and condition of the problem. Patients who complain of experiencing symptoms related to herniated discs are often advised to get an MRI scan done first.

MRI scan is the best non-invasive test available to find herniated and bulging discs and annular tears. Because the spatial resolution of spinal anatomy can be defined to 0.5mm with an MRI scan, doctors can identify with over 95% accuracy the herniated discs in the spine. CT scans use harmful x-rays and have far less accuracy because of factors that reduce visibility of the soft tissue structural changes seen with a herniated disc. CT scans are best for looking at spinal alignment and bony issues as seen with spine fractures. MRI scans provide highly accurate representations of spinal discs and problems going on in and around the discs such as inflammation and degeneration. MRI is considered the gold standard in medicine for evaluating disc injuries.

MRI scans are often used to diagnose and monitor herniated discs. One of the most common ways they are used is to identify the location of the herniated disc(s) in the spine and the degree of nerve compression. If the MRI results indicate a herniated disc, your doctor may recommend additional tests to evaluate the condition better. MRIs are useful for diagnosing herniated discs and bulging discs in the neck and back. 

After your doctor orders your MRI, the technician conducting your MRI will place you in a tube-like device. The device then rotates a magnet around a patient’s body, changing the level of excitation of hydrogen atoms within tissues in the patient’s body. Once the magnetic field is removed, the hydrogen atoms return to their usual resonance state and they release a small quantity of energy which the scanner may detect to produce the image known as the MRI scan. 

The generated MRI scan image depicts anatomy by distinguishing between tissues with a lot of water (such as cerebrospinal fluid or discs) and tissues with little water (such as skin, bone, cartilage, and nerve roots). Once this image is produced, your doctor will examine it for any anomalies to diagnose your condition. MRI scans are particularly sensitive for detecting disc injuries such as a lumbar disc herniation, bulging disc, annular tear which causes back discomfort or even a pinched nerve.

The interpretation of an MRI scan depends on several factors. The challenge with MRI scan results, similar to several other diagnostic tests, is that the "disorder" that appears on the MRI scan is not always the origin of backaches.

To accurately read a lumbar MRI scan for a herniated disc, patients must possess a basic understanding of the anatomical structure of the lumbar spine.There are 5 vertebrae components in the lower back and they are separated by two types of joints including facet and discs. In most cases, these discs are subjected to constant motion causing wear and tear. When the outer layer of the disc is ruptured, called an annular tear, its inner nucleus jelly squeezes out into the spinal canal and forms a hernia. This hernia will often show up as a contrasting spot in an MRI scan.

Fig. 1 MRI for herniated disc with or without contrast

As a general rule of thumb, MRI scan results are interpreted by the physiological symptoms exhibited and experienced by the patient. On its own, an herniated disc might not produce any symptoms in the patient, therefore there are many individuals who live with undiagnosed back conditions. However, when the herniated disc becomes bulged or protruded, it can begin to cause severe pains. An excellent video explaining how spinal disc herniations cause back pain can be found here. 

Back pain usually occurs when the herniated disc becomes inflamed along the posterior annular tear causing pain signals to travel via the sinu-vertebral nerve located along the margin of the annulus fibrosus. Because the nerve fibers along the annulus fibrosus posterior wall are somatic afferent (SA) pain fibers, they will project their pain signals to a region of the brain where highly localized pain is represented called the primary somatosensory cortex. 

Fig. 2 MRI of a herniated disc in the lower back

In the spine, there are a total of 23 intervertebral discs. These discs are tissue joints that protect the spinal vertebral members from unexpected impact by having a soft gel-like interior and a firm outer wall (annulus fibrosus). The outer wall of the disc can sometimes develop a breach called an annular tear, allowing the jelly-like nucleus to squeeze through the annular tear. This is referred to as a herniated disc or bulging disc if the amount of nucleus extruded out of the annular tear is small.

A herniated disc can occur for a variety of causes. Trauma from injury or wear and tear are the most common. The cartilage that joins the discs in the spine to the corresponding vertebral member can become loose and lose elasticity as people get older. Sudden impact and trauma, such as accidents or falls, can also cause herniated discs.

The most common way herniated discs cause symptoms is by irritation of nearby nerves. The interaction between the nucleus pulposus and the small blood vessels within the outer ½ of the annulus fibrosus cause a severe inflammatory response within the annular tear. When the inflammation occurs in the back of the disc where a certain type of pain nerve fiber is present, pain signals travel via somatic afferent (SA) sensory nerves to parts of the brain responsible for localizing the pain. The somatic afferent (SA) fibers end up synapsing on neurons within the post-central gyrus, an area of the brain known as the primary somatosensory cortex. This area of the brain gives pain signals from all over the body their location tag and associated qualities like “sharpness” and “stabbing”. It is only because the posterior annulus is innervated by SA pain fibers that we can easily identify disc pain location and quality from a herniated disc. Add link to animation

The most common symptom of a herniated disc is sharp pain localized directly over the painful inflamed disc(s). The inflammation from the disc herniation can spread to the dural covering around nerves and spinal cord causing irritation of nerves and even headaches. Headaches originating in the neck and moving upwards to the back of the skull are called “cervicogenic” headaches. When the disc is repaired properly with the Deuk Laser Disc Repair technique, the headaches go away permanently.

When inflammation from the herniated disc spreads to the nearby covering around nerve roots, painful sensations can travel down arms (cervical herniations) or legs (lumbar herniation or even around the ribs (thoracic herniations). One of the most prevalent areas to see signs and symptoms of a herniated disc is the nerve root dermatome. A loss of normal sensation in the arms, elbows, and shoulder is one example. Cervical radiculopathy is the medical word for this condition, which is characterized by radicular discomfort in this location and the appearance of a hot sensation radiating outwards from the source of pain. 

The nerve root myotome, which is the muscles in the arm or leg regulated by the nerve root, is likely to be affected by disc herniation. This frequently causes weakness in the muscles in this area, particularly the triceps, shoulders, legs, and upper arm in general. These anatomical parts may also be difficult to move for the patient. 

Below we have highlighted seven of the best surgical treatments available for herniated discs;

In many cases, herniated discs can heal naturally. These cases heal within days or at most 4 weeks. Approximately 90% of herniated disc cases are mild and don’t require surgery.  In such cases, modest treatments such as proper rest for a few days and temporary lifestyle changes for a few weeks only will be enough to alleviate herniated disc symptoms. Patients will often see symptoms disappearing entirely within weeks or even days.If pain or symptoms from a herniated or bulging disc last longer than 4 weeks the patient should have the Deuk Laser Disc Repair performed. Waiting longer will cause other muscles and joints in the body to deteriorate and begin to cause additional pain and dysfunction. Waiting on surgery beyond 1-2 months from symptom onset is ill-advised as it causes more damage to the patient and further robs people of the quality of their life.

A herniated disc squeezing a nerve root may occasionally be alleviated with a variety of physical exercises. These exercises range in difficulty and can be done by anyone, regardless of previous fitness experience or history. Low-impact workouts are especially recommended because they provide the least amount of pain and discomfort while working on specific muscle groups.

The Deuk Spine Institute is a premier concierge spine surgery clinic and outpatient surgical center specializing in minimally invasive surgical procedures and complete spine treatments for back and neck pain relief.

Click here for more information about Deuk Spine Institute and get started on your journey to a pain-free life.