Disc injuries are often the result of car accidents and other traumatic events. Injuries to spinal discs can cause pain and limit a person’s abilities to work and perform their activities of daily living. While the nature and severity of disc injuries can vary, it’s important to understand the differences between disc bulges, herniations, protrusions, and extrusions. These medical terms describe different levels of damage to spinal discs and must often be diagnosed with advanced diagnostic imaging like an MRI.
What is a “Disc” in the Spine?
Your spine is composed of vertebrae (bones) and intervertebral discs. These discs act like little cushions between each of the vertebrae. Spinal discs allow the spine to flex and act as shock absorbers to protect your spine when it moves.
Every spinal disc consists of two main parts:
- Nucleus Pulposus: A soft, gel-like center that provides flexibility and absorbs impact.
- Annulus Fibrosus: A tough, outer layer made up of fibrous tissue that surrounds the nucleus and holds it in place.
A disc in the spine that is healthy allows for smooth, pain-free movement and cushions your spine. When a disc is damaged, like when a disc herniation or bulge results from a rear-end car crash, it can lead to painful limitations, nerve compression, and other symptoms.
What is a Disc Herniation?
A disc herniation results when the inner gel-like material of the disc, i.e., the nucleus pulposus, pushes through a tear or weakness in the outer layer of the annulus fibrosus. This pushing of the disc material outwards causes the disc to “bulge” and, in some cases, to press on nearby spinal nerves or even the spinal cord.
Disc herniations are most common in the lumbar spine but can also occur in the cervical or thoracic spine. The damage caused by a herniated disc is that the displaced nucleus material can impinge on surrounding nerves, leading to pain, numbness, or weakness.
Disc Bulge vs. Disc Herniation vs. Disc Protrusion
There are several different ways to describe the damage caused to the discs in your spine after trauma, such as a car accident or slip and fall. Each term for a disc injury has a very specific meaning and defines the nature and extent of the damage caused to the disc.
Disc Bulge
A disc bulge is a condition where the disc extends beyond its normal boundary but the outer layer of the annulus fibrosus remains intact. With a disc bulge, the nucleus does not break through the annulus, but the overall shape of the disc is distorted and misshapen. Disc bulges are typically considered less severe than disc herniation, but they can still cause intense pain if they’re compressing nearby nerves. The key point to remember with a disc bulge is that it pushes the disc outward but does not rupture the annulus.
Disc Herniation
A disc herniation happens when the nucleus pulposus of the disc pushes through the annulus fibrosus in some way. Disc herniations are more severe than disc bulges because the inner disc material moves beyond the disc’s normal boundary and affects nearby nerves. With disc herniation, the nucleus pulposus breaks through the annulus, potentially compressing spinal nerves. Disc herniations are very common in rear-end car accidents when the car accident victim is at a complete stop.
Disc Protrusion
A disc protrusion is a specific type of disc herniation where the displaced nucleus causes the disc to bulge out unevenly but still remains contained by the outer layer of the disc. In the case of a disc protrusion, the herniation is still limited in scope and the nucleus has not fully escaped from the disc. Disc protrusions can cause localized nerve compression, leading to pain and limitations.
Disc Extrusion
A disc extrusion is a more serious form of disc herniation in which the nucleus pulposus has fully broken through the annulus fibrosus and extends into the spinal canal. A disc extrusion is more likely to cause nerve compression, significant pain, or neurological symptoms. It’s not uncommon for victims of speeding car accidents, with their high-impact forces, to complain of symptoms indicative of a disc extrusion.
With a disc extrusion, the disc material can press on spinal nerves, leading to issues like sciatica or arm pain. The key difference to remember with a disc extrusion is that the nucleus escapes through the annulus pulposus and potentially presses on nearby nerves.
How Does Disc Bulge or Disc Herniation Cause Pain?
The pain caused by spinal disc injuries after a car accident is primarily caused by nerve compression or inflammation of the surrounding spinal tissues. When a spinal disc bulges, herniates, or extrudes, it can press on nearby nerves that exit the spinal column. Those nerves control movement and sensation in various parts of the body, like your arms and legs. When those nerves get compressed, you can experience pain or neurological symptoms.
Nerve Compression
One of the main causes of spine pain caused by a disc injury is nerve root compression. Your spine is surrounded by a network of nerves that control different parts of your body, including the arms, legs, and trunk. Each spinal nerve exits the spinal column through small openings between the vertebrae called “foramina.” When a spinal disc bulges or herniates, it can narrow these openings, putting pressure on the nerves.
Herniated discs in the lumbar spine can compress the sciatic nerve, leading to pain that radiates down the leg, i.e., sciatica. A frequent complaint from victims of head-on car crashes is the feeling of radiating pain into their legs, often caused by nerve compression from a disc injury.
Inflammation
In addition to nerve compression, disc injuries in the spine can cause inflammation in the surrounding tissues. The nucleus pulposus has chemicals and substances within it that can irritate nearby nerves or soft tissues when they leak through a tear in the annulus fibrosus. The inflammation caused by the interaction with the nucleus pulposus materials can cause localized pain in the spine.
What are the Symptoms of a Spinal Disc Injury?
Before your disc injury is diagnosed on an MRI, you can experience a range of symptoms that indicate you have a serious problem with your spinal discs. Your symptoms can vary depending on the location of the disc injury and the degree of nerve compression or inflammation. Some of the most commonly reported symptoms of a disc injury include:
Localized Back or Neck Pain
One of the earliest signs of a disc injury is localized, i.e., direct, pain in the area of the spine where the injury is. This spine pain can be constant or worsen with movement, such as bending, lifting, or twisting. A herniated disc in the lumbar spine (lower back) often causes pain in the lower back, and a herniation in the cervical spine (neck) can result in neck pain.
Radiating Pain / Radiculopathy
When a disc injury compresses a spinal nerve, it can cause radiating pain in the area of the body served by that nerve. This type of pain is often described as sharp, shooting, or burning and can extend from the spine into the arms, legs, or buttocks. Radiating pain from a disc injury is known as “radiculopathy.” A herniated disc in the lower back can lead to sciatica, causing pain that travels from the lower back down the leg.
Numbness or Tingling
Numbness or tingling sensations, in medical terminology, paresthesias, are common symptoms of disc injuries that compress spinal nerves. Car accident victims who have whiplash injuries often complain of numbness and tingling in their arms and legs in the days and months after a crash. Sensations of numbness are typically felt in the same area as the radiating pain and often occur because the compressed nerve is not functioning properly.
Muscle Weakness
In more severe cases of a disc injury, a car accident victim can experience muscle weakness in the affected area. Nerve compression can interfere with the signals that control your muscle movement, resulting in weakness in the arms, hands, legs, or feet. This weakness may cause difficulty with activities such as walking, lifting objects, or gripping. A herniated disc in your cervical spine may cause weakness in the arms, making it difficult to lift objects or perform fine motor tasks.
How is a Spinal Disc Injury Diagnosed with an MRI?
If a patient presents with the symptoms of a disc injury, such as after a car accident, a doctor will often order an MRI to confirm the diagnosis. An MRI gives detailed images of the soft tissues in the spine, including your spinal discs, the nerves, and the spinal cord.
MRI is the most reliable tool for diagnosing disc injuries, as it can detect even small changes in the structure of the discs and soft tissues if there is a disc herniation or disc extrusion. In some cases, additional tests like CT scans or X-rays can be used to rule out other causes of pain, such as fractures or bone spurs.
Disc bulges, herniations, protrusions, and extrusions are common after car accidents and other traumatic events. These types of spine injuries occur when the structure of the spinal discs is compromised, and they lead to pain, nerve compression, and other symptoms. While insurance companies sometimes argue these injuries are due to pre-existing conditions, the reality is that many disc injuries become symptomatic only after a trauma.
If you’ve been involved in a car accident or slip and fall, it’s best to get medical treatment right away. Speaking with a seasoned personal injury lawyer at Horn Wright, LLP, is the next best step to take after that, to make sure your rights are protected in the event your injuries are permanent or you continue to incur medical expenses and lost wages. Call Horn Wright LLP, today.