Osteomyelitis is a serious bacterial infection that occurs in the bones. When this type of infection occurs in the spine, it can lead to debilitating back pain. Thankfully, this condition is rare and only occurs in two of every 10,000 people. Here are the causes, risk factors, symptoms/diagnosis, and treatments for osteomyelitis.
Causes of osteomyelitis
Most osteomyelitis is caused by Staphylococcus aureus, a type of staph infection, but other germs and bacteria can also cause this bone infection. This infection can start underneath a sore on the skin and spread to the bone through the blood. Osteomyelitis can also occur after any surgery that involves the bone, including surgery after an injury or in back surgery that includes placing rods or pins in the spine.
For children, osteomyelitis most commonly occurs in the long arm and leg bones, but in adults the spine and pelvis is most commonly affected.
A weakened immune system is one of the main risk factors for osteomyelitis, but other risk factors include:
- Diabetes: The majority of osteomyelitis cases occur in conjunction with diabetes
- Sickle cell disease: This disease affects African Americans disproportionately, making this group more susceptible to bone infection
- HIV or AIDS: These are diseases that result in poor immune function and decrease a person’s ability to fight infection
- Recent surgery or injury: Hip and knee replacements increase the chances of developing bone infection, and injuries such as broken legs can also increase the risk
- Alcoholism: Excessive, chronic alcohol consumption taxes all of the body’s systems, including the ability of the body to clear out toxins and resist infection
Other risk factors include rheumatoid arthritis, long-term steroid use, intravenous drug use, and poor blood supply. People without a spleen are at higher risk of osteomyelitis, as the spleen filters blood as part of the immune system, fighting bacteria that causes other diseases such as meningitis.
Symptoms can range from mild to severe, increasing as the infection progresses. Symptoms include:
- Back pain: Whether located in the spine or pelvis, osteomyelitis can cause severe back pain, especially at night
- Fatigue: Back pain at night leads to exhaustion during the day, which can increase back pain during the day also
- Bone pain: This is extreme tenderness or aching felt in the bones
- Swelling, redness, or warmth: Similar to signs of an infected wound, osteomyelitis presents with swelling, warmth, and redness in the area of the bone infection
- Fever and chills
- Malaise: This is defined as a general, ill-defined feeling of discomfort or sense of uneasiness
Osteomyelitis’s signature symptom is definitely pain that is felt in the bones. The other symptoms of infection are fairly common to all types of infection, but the feeling of back pain that is not muscular or superficial in nature can be disconcerting, especially when accompanied by the feeling that something just isn’t right.
In addition to a physical examination of the site, there are a number of tests and scans that can be run to confirm an osteomyelitis diagnosis. Doctors may take blood cultures, looking for an increase in white blood cells that indicate an infection somewhere in the body. Bone scans, biopsies, and X-rays can also be helpful diagnostic tools that pick up inflammation or other abnormalities in the bone. Other blood work such as a complete blood count (CBC) may be run, and doctors may order a magnetic resonance imaging (MRI) scan of the bone. MRIs are usually reserved for diagnosis of soft-tissue injuries, but they can also pick up swelling and inflammation in the marrow of the bones without using radiation.
Children who develop osteomyelitis usually have an acute type. Acute osteomyelitis is easier to treat and is generally resolved quickly. Adult osteomyelitis is usually chronic and comes with other health conditions and complications, making treatment more difficult. In general, the following steps are taken to eliminate the infection and prevent future infections from occurring in the same area.
- For all cases, strong antibiotics are administered immediately, usually intravenously, even at home. The course of antibiotics generally lasts four to six weeks and will be repeated as needed to eliminate the infection.
- If the infection has killed parts of the bone, surgery to remove the bone is recommended for both children and adults, especially if the infection is resistant.
- For osteomyelitis that occurs as a result of an infected joint replacement, doctors will generally want to replace the affected joint as soon as the infection is cleared.
- If there are metal plates or other surgical pins inserted, they may need to be replaced.
- For patients with diabetes, doctors will re-visit the treatment plan for that condition to make sure it is under control.
As stated above, acute osteomyelitis is usually successfully treated, but chronic osteomyelitis that occurs most often in adults is harder to treat and more likely to re-occur. The success of treatment depends on the patient’s health, where the infection is located, the cause of the infection, and how well the patient adheres to the treatment plan. If a replacement joint is the case of infection and can be safely removed and replaced with an uninfected joint, the prognosis is more positive.
Patients with poor blood supply, diabetes, or another immune condition can struggle with osteomyelitis in the same area for years. There is a special risk of amputation due to infection for those patients with diabetes. The body is not able to help clear out the infection, even with treatment, especially if the diabetes is poorly controlled or treatment protocols are not strictly followed.
Chronic osteomyelitis can lead to chronic back and joint pain that is hard to control with medications. If you have any of the above risk factors, practice good hygiene to help prevent osteomyelitis. For more on prevention, visit NHS Choices website.
Image by Ed Uthman via Flickr