Lumbar intervertebral infection?

Lumbar intervertebral infection is a relatively common disease at present. There are many causes of lumbar intervertebral infection. Most people tend to think that this disease is not a serious disease and will not pay attention to it when they suffer from it. In fact, lumbar intervertebral infection does not seem to be a serious disease, but it is very harmful to the human body and seriously affects people's daily life and work. We must pay attention to it.

Pathogenesis of intervertebral disc infection

There are two ways that bacteria enter the intervertebral space:

1. Contaminated surgical instruments are directly introduced into the intervertebral space. In the past, the most common infection was post-disc surgery infection, with an incidence rate of between 0.1% and 0.5%. In recent years, percutaneous disc aspiration and endoscopic discectomy have become popular. If the instruments are not strictly sterilized, intervertebral disc infection may occur. Therefore, the overall number of cases has increased.

2. Spread through the blood It is generally believed that the intervertebral discs of adults have no blood supply, but some people believe that there is sufficient blood supply under the age of 30, and even that there is still blood supply in old age. As people age, the blood supply from adjacent vertebrae penetrating the vertebral bone lamina into the nucleus pulposus gradually decreases, but sufficient collateral circulation can still be obtained from the surrounding blood vessels. Therefore, it can be assumed that the source of disc infection is similar to that of vertebral body infection. The primary lesions mostly originate from the skin, mucous membranes or urinary tract, and may be caused by reflux through the Batson spinal venous plexus. There are reports of the disease occurring after catheterization with positive blood cultures. Infection from the urinary tract is the most common.

Symptoms of intervertebral disc infection

The onset of intervertebral disc infection caused by surgical contamination may be sudden or slow. Infections caused by hemolytic Staphylococcus aureus often have an acute onset, with chills and high fever, aggravated low back pain, and obvious symptoms of nerve root irritation. Patients dare not turn over due to severe pain, and even slight vibrations can trigger convulsion-like pain and cause screaming. Physical signs include lumbar muscle spasm and tenderness, movement disorders, and aggravation of existing nerve root irritation signs. During the straight leg raising test, it is even difficult for the heels to leave the bed. Patients often refuse to undergo any examination due to severe pain. Infections caused by less toxic bacteria, such as Staphylococcus aureus, have a slow onset, milder systemic symptoms and signs, and tend to be chronic in course.

Hematogenous intervertebral disc infection is generally seen in young adults and is relatively rare in children, with a higher incidence in the lumbar spine. The onset is generally slow, with symptoms such as fever and loss of appetite. People with lumbar spine disease suffer from back pain and sciatica. Physical signs include tenderness, lumbar muscle spasm and movement disorders. Symptoms can be relieved after treatment with plaster and antibiotics, but they will worsen if there is excessive activity or treatment is stopped. The course of the disease tends to be chronic. During the febrile period, the white blood cell count increases, but the erythrocyte sedimentation rate continues to increase, indicating that the disease is still active.

The most serious complication is paraplegia. Kemp reported a group of cases in which the incidence of paraplegia was as high as 40%, and half of the cases had concurrent diabetes.

The X-ray manifestations of intervertebral infection do not appear until about one month after onset and can be divided into four stages:

1. The first stage is the narrowing of the intervertebral disc, which occurs within the first 3 months of onset.

2. The second stage begins 3 months after the onset of the disease, characterized by progressive sclerosis of the subchondral bone and increased density of adjacent vertebrae, which is particularly obvious on lateral views. This is due to the formation of new bone under the periosteum.

3. In the third stage, the bone plates adjacent to the vertebrae become progressively irregular and reactive sclerosis occurs at the vertebral margins, indicating the progression of inflammation.

4. In the fourth stage, the intervertebral space presents balloon-like changes, accompanied by vertebral erosion, and changes in vertebral density can still be seen.

The diagnosis of intervertebral disc infection is relatively late, especially hematogenous disc infection, which takes at least 3 months and at most 18 months after onset, which is almost 3 times later than that of suppurative vertebral osteomyelitis. MRI examination can detect lesions at an early stage. On the MRI film, symmetrical abnormal inflammatory shadows can be seen on the two corresponding vertebrae in the diseased intervertebral space.