Spondylodiscitis – Inflammation of the Spine, Bacterial Infection, Diagnosis, and Treatment

The human spine consists of approximately 33 vertebrae, which are connected to one another by intervertebral discs. Since the coccygeal vertebrae fuse together to varying degrees in each person, the total number of vertebrae varies from person to person.

The intervertebral discs act as cushions between the individual, rigid vertebrae. They ensure that the spine remains flexible and that impacts are absorbed while walking.

Many people are familiar with spinal conditions such as a herniated disc or lumbago. Spondylodiscitis is less well known. The term comes from Latin and is composed of the syllables

• "spondyl" (vertebra),
• “disc/dis” (intervertebral disc), and
• “itis,” the suffix indicating an inflammatory condition.

Spondylodiscitis is therefore an inflammation of the vertebrae and intervertebral discs, meaning that both the vertebrae and the discs are affected. If only the vertebrae are inflamed, the condition is called spondylitis. If only the intervertebral discs are inflamed, it is called discitis.

In spondylodiscitis, the vertebral bodies and intervertebral discs are inflamed © bilderzwerg | AdobeStock

Spondylodiscitis manifests as severe back pain. The condition is accompanied by pain on exertion that worsens with movement. In the affected area of the back, the pain feels like a throbbing or pressing sensation.

Often, the cause of the pain is not identified until after the patient has endured a long period of suffering.

In addition to back pain, some patients exhibit general signs of inflammation. They experience fever and night sweats and feel unwell. This is usually accompanied by physical wasting, which in turn

• weakness,
• loss of appetite, and
• weight loss

. 

In advanced stages, neurological deficits such as numbness or paralysis may also occur.

Spondylodiscitis is usually caused by a bacterial infection. In most cases, the bacterium Staphylococcus aureus is the causative agent. However, fungi and viruses can also cause spondylodiscitis.

A basic distinction is made between specific spondylodiscitis and nonspecific spondylodiscitis.

Specific spondylodiscitis (also known as skeletal tuberculosis) is caused by tuberculosis bacteria. It presents less acutely than nonspecific spondylodiscitis and tends to have a more insidious course. The infection spreads through the bloodstream. However, this disease has since become rare in our region.

In addition to the aforementioned bacterium, all other pathogens that cause suppuration can also trigger nonspecific spondylodiscitis. The disease is accompanied by acute pain. Open fractures can be a cause of the inflammation. Bacteria can enter the body—and thus the bone—through the wound.

However, the pathogens can also reach the spine via the bloodstream from sites of inflammation anywhere in the body.

Risk factors for developing spondylodiscitis include:

• diabetes,
• excessive alcohol consumption,
• regular use of corticosteroids, and
• many other medical conditions.

An early diagnosis can significantly improve the course of spondylodiscitis and shorten the duration of the illness. If the disease remains untreated, it can lead to severe symptoms and even a life-threatening course.

However, treatment with antibiotics is often sufficient. The body can then bring the inflammation under control. Nevertheless, long-term damage often remains: In many people, the intervertebral discs remain damaged and the vertebrae stiffen over time.

Treatment for spondylodiscitis initially focuses on pain management.

Before the actual treatment begins, the pathogen or spectrum of pathogens must be identified. This requires a biopsy (tissue sample) or surgery. The biopsy is performed under CT guidance, even if surgery is not performed. Whether surgery is necessary to treat spondylodiscitis depends

• the extent of the damage,
• the pain, and
• neurological deficits

.

If surgery is performed, the surgeon debrides the inflamed area and stabilizes it. This allows for rapid mobilization and pain relief for the patient.

Without surgery, the patient is initially advised to rest in bed until the pain is under control. Antibiotic therapy is usually administered for 6 to a maximum of 12 weeks. This eliminates the source of inflammation and prevents it from spreading to other parts of the body.

If the inflammation is not bacterial but is caused by fungi or other pathogens, antifungal or antiparasitic therapy must be administered.

In addition to medication, the affected vertebral region is immobilized. Bed rest and a plaster cast have proven effective for this purpose.

After about 10 weeks, exercise therapy is cautiously initiated to stabilize the spine.

What is spondylodiscitis?

Spondylodiscitis is an inflammation of the spine that affects both the intervertebral disc and the adjacent vertebral bodies. It is usually caused by a bacterial infection; less commonly, it is a specific form of spondylodiscitis, such as that associated with tuberculosis.

What are the symptoms of spondylodiscitis?

Typical symptoms include persistent back pain, often in the lumbar spine, as well as general signs of illness. In severe cases, neurological deficits may occur due to pressure on the spinal cord.

How is spondylodiscitis diagnosed?

Diagnosis involves a detailed medical history, physical examination, and imaging studies. MRI is the most important method, supplemented by CT, blood cultures, and pathogen detection via puncture.

How is spondylodiscitis treated?

Treatment for spondylodiscitis is usually conservative, involving targeted antibiotic therapy and immobilization. Surgical treatment is necessary in cases of abscess, spinal instability, or neurological deficits.

What complications can occur?

If left untreated, the infection may spread, leading to sepsis or spinal instability. Abscesses, neurological damage, and limited spinal mobility are also possible complications.