Inflammatory and Infectious Disorders

Ankylosing Spondylitis
Arachnoiditis
Discitis
Osteoporosis
Sacroiliitis

Infections of the spinal column are not common, but they are important because they are difficult to diagnose and there are serious consequences in the delay of an accurate diagnosis. In spite of extensive studies, confusion still surrounds the classification of spinal infections, their diagnosis and treatment. Because a microbiologic diagnosis is not sought in every case, diagnosis is often presumptive. Spinal infections are widely divided into two categories, vertebral osteomyelitis and disc space infections. Disc space infections are particularly controversial because it can be argued that except in children, discs don't have their own blood supply, and therefore, most infections involving disc space are secondary to a primary vertebral body infection. Following are some common infections and inflammatory disorders of the spine.

Ankylosing Spondylitis
Ankylosing Spondylitis (AS) is classified as a rheumatologic disorder of the lumbar spine. It is considered one of the so-called sero-negative arthropathies. It's a type of arthritis that causes the joints in the lower back - the sacroiliac joints and the joints of the lumbar spine - to become inflamed. It will also frequently affect the hips and other peripheral joints. Ankylosing spondylitis comes from Latin words meaning, "bent spine." The disease has been present since antiquity and has been found in the skeletal remains of Egyptian mummies. AS usually strikes a person between the teen years and the age of 30. "The classic picture of AS is a man between the ages of 15 and 40 with intermittent, dull low back pain and stiffness slowly progressing over a period of months." Although AS was once considered to predominantly affect men, it is now known to affect women as well. Although women seem to have less progressive spinal disease, their peripheral joints tend to be more severely involved. *

Symptoms
The pathogenesis of AS is not known, but a genetic predisposition to the disorder does exist. Patients with AS often have stiffness in the morning that lasts a few minutes to several hours, sometimes coupled with fatigue. Prolonged inactivity can cause more pain and stiffness in the back, unlike other lower back disorders, which will often improve with rest. With AS, there may be pain and stiffness in the shoulders, hips or other joints as well. After a few years with the disorder, there may be pain in the middle or upper part of the back and gradual stiffening of the spine and eventually the neck. The classic deformity associated with AS is a rigid kyphosis, which causes a stiff, hunched forward posture.

Diagnosis
Ankylosing spondylitis is often diagnosed after your doctor takes a thorough history, performs a physical examination, and orders appropriate x-rays and laboratory studies. There is a significant association of AS with a commonly performed blood test that detects the presence or absence of a particular marker in the blood called the human leukocyte antigen B27 (HLA-B27). A positive test, along with other clinical correlations, will help to establish the diagnosis of AS.

Return to top

Arachnoiditis
Arachnoiditis is inflammation of the delicate, web-like membranes that cover the spinal cord. It may result from infection, such as meningitis, or from trauma such as a fall, surgery, lumbar puncture, or myelography (a test to diagnose disorders of the spinal canal and cord). If the inflammation becomes chronic, it means that the nerve roots (peripheral nerves exiting the spinal cord) are damaged.

As a result, people will experience chronic debilitating pain in the low back and legs. Symptoms include weakness, numbness, tingling, stinging, and burning in the legs. Non-surgical treatment focused on pain management is generally recommended. Surgery to remove adhesions is generally not recommended because scar tissue may continue to develop, and the spinal canal may be exposed to additional trauma. Neurostimulation or intrathecal drug delivery may be considered in instances where conservative pain management treatments, such as exercise or other manual techniques, have failed.

Return to top

Discitis
Discitis is a low-grade infection that affects the disc space between two vertebrae. Although discitis is uncommon, children under ten are usually the ones affected by this condition which is the result of an inflammation caused by staphylococcus, viruses or other inflammatory processes.

Discitis is characterized by the slow onset of severe back pain and may or may not be associated with fever, chills, sweats, feeling tired, loss of appetite or other symptoms. The diagnosis is usually made by seeing narrowing of the disc space between two vertebrae and a bone scan that shows that the disc and adjacent vertebrae are "hot" on the scan. This condition can be very painful and is often aggravated by any movement of the spine. The pain often travels to other parts of the body including the abdomen, hip, leg, or groin. It usually occurs in the lower (lumbar) back and upper (thoracic) back.

It is a non-tubercular infection of the spine. The adjacent vertebral margins of the infected disc become eroded, with the degree of erosion depending on the amount of destruction resulting from the infection. The areas of erosion become recalcified as the healing process occurs and eventually an interbody fusion is evidence of a successful resolution of the disease.

Young children with this condition are usually irritable and uncomfortable and refuse to sit up, stand or walk. The treatment of discitis generally involves antibiotics, rest, and a brace. Surgery is rarely needed.

Return to top

Osteoporosis
More than 1.3 million osteoporosis-related fractures are reported in the United States each year.

Osteoporosis is a condition in which the skeleton contains a smaller total quantity of bone tissue than normal for the age, sex and culture of the patient. Skeletal growth usually peaks at about age 20 and by age 65, most people have lost 30 percent of the bony tissue they had at their peak of skeletal maturity. Because of this, osteoporosis is described medically as a phenomenon rather than a disease or pathologic condition.

A person with osteoporosis has a less than normal amount of bone tissue for their age, sex and culture in addition to a clinical disability, often in the form of consequent vertebral compression fractures, which occur spontaneously or as a result minor incidents that would not harm the average person.

Therefore, if a person has an osteoporotic skeleton without having the associated clinical disabilities, the patient may have some other medical problem. "The significance is that the medical disease, not the skeleton, needs treatment."

Diagnosis
Ordinary X-ray views of the spine can reveal the osteoporosis. In addition, a patient may reveal a history of fractures following minor trauma and may complain of disability because of skeletal pain.

Return to top

Sacroiliitis
Sacroiliitis is an inflammation of the sacroiliac joint. A patient with this disorder can present in a variety of different ways. Often a patient with sacroiliitis will come to their physician with a sudden onset of fever, pain and decreased range of motion. Non-acute patients may or may not present with a fever. Patients are often ill, limping, in pain and showing a decreased range of motion, but the symptoms are still generally vague. All patients with sacroiliitis will have sacroiliac joint pain, but this symptom can be overlooked because of the patient's refusal to move due to their pain.

The sacroiliac joint is encompassed in a large amount of ligamentous and fibrous tissue for added stability. Conditions that can predispose patients to sacroiliitis include trauma, pregnancy, infections of the skin, osteomyelitis, urinary tract infection, endocarditis and drug addition. This type of infection is seen with some frequency in intravenous drug users.

In the physical examination, sometimes the sacroiliac joint pain can be mistakenly attributed to another source, such as septic hip, psoas abscess, malignancy, sciatica, herniated disc, pyelonephritis, ankylosing spondylitis or appendicitis. Subacute sacroiliitis is hard to diagnose and the delay in proper diagnosis and treatment can lead to increased joint destruction, potential rupture, abscess formation and morbidity.

A clinical, physical and laboratory evaluation is critical for an accurate and early diagnosis of sacroiliitis. In the physical examination it is important for the physician to localize the pain and decreased motion. In most cases a blood culture can make the diagnosis. The exception to that rule is intravenous drug users who have self medicated themselves with an antibiotic, masking an accurate blood culture. An open biopsy and culture may be required to establish an accurate diagnosis and to identify the correct infectious agent.

Return to top