How Degenerative Disc Disease Create Reoccurring Back Pain

When patients hear the words “degenerative disc disease,” they often imagine that their spine is crumbling, wearing out, or permanently damaged. Fortunately, the reality is usually less frightening.

Degenerative disc disease is not a disease in the same sense as an infection or cancer. It is a descriptive term for age-related and stress-related changes within the intervertebral discs. These changes are extremely common, and many people with disc degeneration on an X-ray or MRI have little or no pain.

For other patients, however, changes within a disc can become painful. The pain may arise from altered mechanics, irritation of the outer disc fibers, inflammation within and around the disc, or irritation of a nearby spinal nerve. In some cases, the inflammatory chemistry surrounding an injured disc may be just as important as the size of a disc bulge.

This is sometimes described as chemically mediated discogenic pain or chemical radiculitis.

Discogenic pain is complex and does not have a single universally accepted diagnostic test. Degeneration, mechanical disruption, inflammation, nerve sensitization, and changes within the nervous system may all contribute to a patient’s symptoms.

What Is an Intervertebral Disc?

Intervertebral discs are flexible structures located between the vertebrae. They help distribute physical loads, absorb shock, and allow controlled movement of the spine.

Each disc has three major components:

• Nucleus pulposus: the softer, gel-like center of the disc
• Annulus fibrosus: the strong outer layers surrounding the nucleus
• Cartilaginous endplates: the interfaces connecting the disc to the vertebral bodies above and below

A healthy disc contains water-binding molecules called proteoglycans. These molecules help the disc attract and retain fluid, allowing it to resist compression. As a disc degenerates, it may gradually lose hydration, elasticity, and height. Small fissures may also develop within the annulus fibrosus.

These changes can alter how forces are transferred through the spine and may increase stress on the disc, facet joints, muscles, ligaments, and surrounding tissues.

Disc Degeneration Does Not Automatically Mean Pain

One of the most important principles in spinal care is that an imaging finding is not automatically a diagnosis.

Disc narrowing, dehydration, osteophytes, annular fissures, and disc bulges become increasingly common as people get older. Many of these findings are present in people who feel completely normal.

An X-ray or MRI must therefore be interpreted alongside the patient’s history, physical examination, neurological findings, movement patterns, and symptom behavior. A severely degenerated disc may be relatively quiet, while a less dramatic-looking disc injury may be highly inflammatory and painful.

Imaging can reveal structural changes, but it cannot always determine which structure is producing pain. Current imaging findings are often nonspecific when considered separately from the clinical examination.

Can a Degenerated Disc Become Painful?

A degenerating disc may produce symptoms through several overlapping mechanisms.

1. Mechanical Disc Pain

Loss of hydration and changes in disc structure can alter normal spinal mechanics. Certain positions, movements, or loads may place stress on damaged portions of the annulus.

Mechanical disc pain may be aggravated by prolonged sitting, bending, lifting, vibration, coughing, or repeated flexion. Some patients experience central lower-back pain, while others feel referred discomfort in the buttock, hip, or thigh.

2. Pain From the Outer Annulus

The deeper portion of a healthy disc has very limited nerve supply. The outer annulus, however, contains nerve endings capable of transmitting pain.

When fissures extend toward the outer annulus, inflammatory chemicals and mechanical stress may stimulate these sensitive nerve endings. Degenerative discs may also develop abnormal nerve ingrowth into areas that normally have little innervation, potentially making the disc more sensitive.

Discogenic pain may therefore involve both structural disruption and sensitization of nerve fibers within and around the annulus.

3. Mechanical Nerve-Root Compression

A protruding or herniated disc can physically narrow the space surrounding a spinal nerve root. This may cause radiating pain, numbness, tingling, or weakness in an arm or leg.

The location, size, and direction of the disc herniation matter, but the amount of visible compression does not always perfectly predict symptom intensity.

4. Chemical Irritation and Inflammation

Disc material does not have to severely crush a nerve to irritate it.

When the nucleus pulposus or inflamed disc tissue is exposed to the outer annulus, epidural space, nerve root, or dorsal root ganglion, it can initiate an inflammatory response. Cytokines, enzymes, prostaglandins, nitric oxide, and other inflammatory substances may increase the sensitivity of nearby nerves.

This helps explain why a relatively small disc protrusion can occasionally produce intense radiating pain, while a larger protrusion may cause fewer symptoms in another patient. Mechanical compression and chemical inflammation commonly coexist and can amplify one another.

What is Phospholipase A2?

Phospholipase A2, commonly abbreviated PLA2, refers to a family of enzymes involved in lipid metabolism and inflammatory signaling.

Cell membranes contain molecules called phospholipids. PLA2 acts on these phospholipids and can release arachidonic acid. Arachidonic acid can then enter biochemical pathways that produce inflammatory signaling molecules, including prostaglandins and leukotrienes.

PLA2 activity can also produce lysophospholipids, which may affect cell membranes and participate in inflammatory reactions.

PLA2 is a normal part of human biology. The problem is not simply that the enzyme exists. The concern is that increased or poorly regulated PLA2 activity near an injured disc or nerve may contribute to inflammation, membrane irritation, and heightened nerve sensitivity.

Can PLA2 Irritate a Spinal Nerve?

When disc tissue is injured or displaced, inflammatory mediators associated with the nucleus pulposus may come into contact with tissues that normally remain separated from it.

PLA2 may contribute to nerve irritation through several related pathways:

• Promoting the release of arachidonic acid from cell-membrane phospholipids
• Supporting the production of inflammatory prostaglandins and leukotrienes
• Increasing inflammatory activity around the nerve root
• Contributing to irritation of nerve-cell membranes
• Lowering the threshold at which a nerve begins transmitting pain
• Participating in interactions with cytokines, nitric oxide, and other inflammatory mediators

A sensitized nerve can react strongly to pressure or movement that would not ordinarily be painful. This is one reason inflammation may magnify the effects of relatively modest mechanical compression.

Experimental studies have shown that applying nucleus pulposus material near nerve tissue can produce pain-related behavior and inflammatory changes even without substantial mechanical compression. PLA2 and nitric oxide have been identified as possible contributors to this response. These findings support the biological plausibility of chemically mediated nerve irritation, although animal studies do not reproduce every aspect of a human disc disorder.

Discogenic Pain, Referred Pain, and Radicular Pain

These terms are often used interchangeably, but they describe different clinical experiences.

Discogenic Axial Pain

This is pain believed to originate primarily from the disc itself. It is often felt in the neck or lower back and may refer into the shoulder blade, buttock, hip, groin, or upper thigh.

Referred Pain

Referred pain is perceived away from its source but does not necessarily follow the distribution of a single spinal nerve. Disc, facet-joint, and sacroiliac-joint pain can produce overlapping referral patterns.

Radicular Pain

Radicular pain occurs when a spinal nerve root or its dorsal root ganglion becomes irritated. The pain may travel into an arm or leg and is often described as sharp, burning, electric, or shooting.

Radiculopathy

Radiculopathy means that nerve-root dysfunction has produced an objective neurological deficit, such as measurable weakness, altered reflexes, or sensory loss. A patient can experience intense radicular pain without necessarily having a true radiculopathy.

Making these distinctions helps guide examination, imaging decisions, treatment, and referral.

Symptoms of a Painful Disc Disorder

Symptoms vary depending on the spinal level, tissues involved, and whether a nerve root is irritated. Patients may experience:

• Central neck or lower-back pain
• Pain aggravated by sitting, bending, lifting, or twisting
• Morning stiffness or stiffness after prolonged inactivity
• Pain referred into the buttock, hip, thigh, shoulder, or shoulder blade
• Burning, tingling, or electric pain traveling into an arm or leg
• Numbness or altered skin sensation
• Muscle weakness
• Pain aggravated by coughing, sneezing, or straining
• Difficulty finding a comfortable sitting or sleeping position

These symptoms are not unique to the disc. Similar complaints can arise from facet joints, sacroiliac joints, muscles, peripheral nerves, spinal stenosis, hip disorders, and non-musculoskeletal conditions. A careful examination is necessary before attributing pain to degenerative disc disease.

How Is Discogenic or Chemically Mediated Pain Evaluated?

The evaluation begins with the clinical history. Important details include how the pain started, which positions aggravate it, where it travels, and whether numbness, weakness, or changes in reflexes are present.

A physical examination may include:

• Spinal range-of-motion testing
• Postural and biomechanical evaluation
• Orthopedic stress tests
• Neurological testing
• Muscle-strength and reflex testing
• Sensory examination
• Nerve-tension testing
• Assessment of the hips, pelvis, and surrounding joints

X-rays are useful for evaluating disc-space narrowing, alignment, osteophytes, arthritis, instability, and other osseous changes. MRI provides greater detail regarding the discs, nerve roots, spinal canal, and other soft tissues.

Imaging may be appropriate when symptoms are severe, persistent, progressive, associated with neurological loss, or suggest a condition requiring a different form of treatment. Imaging should support the clinical evaluation rather than replace it.

Conservative Management

Many patients with disc-related pain improve without surgery. Conservative management is individualized according to the patient’s examination findings, neurological status, tolerance, and stage of recovery.

Management may include:

• Temporary modification of aggravating activities
• Carefully selected spinal manipulation or mobilization
• Flexion-distraction or other low-force techniques when appropriate
• Therapeutic exercise
• Core and hip strengthening
• Mobility exercises
• Ergonomic and lifting instruction
• Walking and gradual return to activity
• Supportive physiotherapy modalities
• Coordination with medical providers when medication, injections, or surgical consultation may be appropriate

Chiropractic treatment does not replace a degenerated disc, reverse every structural change, or directly “flush out” PLA2. The purpose of conservative care is to improve movement, reduce mechanical aggravation, support normal activity, decrease disability, and create an environment in which irritated tissues can settle.

Treatment should be modified or discontinued if it aggravates neurological symptoms or fails to produce meaningful improvement.

When Is Prompt Medical Evaluation Necessary?

Seek prompt medical attention when back or neck pain is accompanied by:

• Progressive muscle weakness
• Loss of bowel or bladder control
• Numbness in the saddle or groin region
• Severe difficulty walking
• Symptoms affecting both legs
• Fever or unexplained illness
• Unexplained weight loss
• A history of cancer
• Major trauma
• Severe, unrelenting night pain

These findings do not always indicate a medical emergency, but they require appropriate investigation.

The Disc Is More Than a Mechanical Cushion

Disc pain is not simply a matter of one bone “pinching” a nerve. The intervertebral disc is a living biological structure capable of degeneration, repair, inflammation, and interaction with the nervous and immune systems.

In some patients, mechanical compression is the dominant problem. In others, inflammation and nerve sensitization may play a substantial role. Frequently, both processes are present at the same time.

Understanding this relationship helps explain why MRI findings and symptom intensity do not always match—and why treatment must be based on the complete patient rather than a single image.

Schedule an Evaluation at Innova Pain Clinic

If you are experiencing recurring lower-back pain, neck pain, sciatica, radiating arm pain, numbness, or difficulty remaining active, a thorough examination can help identify the likely source of your symptoms and determine the most appropriate next step.

At Innova Pain Clinic, we provide individualized chiropractic care for patients in St. George and the surrounding Southern Utah community. When additional imaging or medical evaluation is needed, we will explain our findings and help coordinate the appropriate referral.

Schedule an Appointment

Live. Play. Recover.

This article is intended for general educational purposes. It does not provide an individual diagnosis and is not a substitute for an examination by a qualified healthcare professional.