What Is Osteomyelitis?

Overview

Osteomyelitis is a painful infection of the bone caused by bacteria or fungi. It causes pain in the legs or other bones, such as in the back or arms. The infection usually reaches the bone by travelling through the bloodstream, spreading from a tissue nearby or as a result of an injury which can expose the bone to infection.¹

Types of osteomyelitis

There are three types of osteomyelitis: acute osteomyelitis, chronic osteomyelitis and vertebral osteomyelitis.¹

• Acute osteomyelitis – This type of infection comes on suddenly and rapidly develops over a period of 7 to 10 days. Symptoms may begin with a fever followed by pain in the affected area a few days later. This is most common in children and is easier to treat
• Chronic osteomyelitis – This type of infectious disease does not go away with treatment. It causes bone pain and recurring build-up of pus. In rare cases, it does not have any symptoms and may even go undetected for months or years. People with certain medical conditions such as diabetes, HIV and peripheral arterial disease have a higher risk of developing chronic osteomyelitis
• Vertebral osteomyelitis – This type of osteomyelitis affects the spine and causes chronic back pain, which makes movement difficult. It does not respond to regular treatment methods like painkillers, heat packs etc

Causes of osteomyelitis

Osteomyelitis is an infectious disease and is most commonly caused by staphylococcus bacteria which is usually found in the skin or the nose. Bacteria can enter the bone in many different ways, including:^2,3

• The blood – Bacteria in other parts of your body can circulate in your blood and settle in a weakened spot in the bone
• Injuries – A severe puncture wound or bone fracture can provide a pathway for bacteria to enter your bone or nearby tissue
• Surgery – Osteomyelitis can occur as a result of direct contamination during surgeries e.g. joint replacement surgery or repair fractures

Signs and symptoms of osteomyelitis

Symptoms of osteomyelitis include:^1,4

• Bone pain
• Fever
• Limited and painful movement
• Redness and swelling of the infected area
• Nausea and vomiting
• Loss of appetite

Management and treatment for osteomyelitis

Osteomyelitis is either treated with medication or surgery.^5,6 A bone infection may take a long time to heal so it is best if you start treatment within the first few days of noticing symptoms. If left untreated, a bone infection can cause permanent damage.

Medications

• Antibiotics

Osteomyelitis is often treated with oral antibiotics, usually taken for 4 to 6 weeks, or up to 12 weeks if the infection is severe. You may even need to stay in the hospital and be given intravenous antibiotics.

• Antifungals

If you have osteomyelitis, which is caused by a fungal infection, your GP may prescribe you oral antifungal medication to take for several months.

• Painkillers

You may be prescribed painkillers to ease the pain

Surgery

A common treatment of osteomyelitis is surgery which involves removing parts of the bone that are infected or dead.

An operation may include:

• Draining the infected area – A surgeon will drain the build-up of pus or fluid in the bone
• Removing the infected bone or tissue
• Restoring blood flow to the bone – After removing the infected bone/tissue, a surgeon will fill the empty space with a piece of bone or muscle and skin from another part of the body or use temporary fillers
• Amputating the affected limb – This is used as a last resort to stop the infection from spreading

Diagnosis of osteomyelitis

Your GP will examine the area around the affected bone for any swelling or tenderness. They may then order some tests to find out if you have a bone infection.^1,5

• Blood tests

A blood test can reveal if there are elevated levels of white blood cells, which may be a sign of infection or inflammation. Additionally, a blood culture identifies bacteria in your bloodstream.

• Imaging tests

Imaging tests such as X-rays, MRIs, CT scans and ultrasounds can reveal detailed images of the damaged bone and even the soft tissue that surrounds them.

• Bone biopsy

A bone biopsy is when a small sample of fluid is taken from the affected bone and then examined. This can reveal what type of bacteria has infected your bone, thus allowing your doctor to choose an antibiotic that works well for that type of infection.

Risks factors

Anyone can get osteomyelitis, but you are more likely to get infected if:⁷

• You have recently fractured or broken a bone
• You have a weakened immune system
• You have recently had surgery  involving a bone
• You have had osteomyelitis in the past (chronic osteomyelitis)
• You have had a recent injury or have a wound
• You have poor blood circulation ( e.g. poorly controlled diabetes, sickle cell anaemia, peripheral artery disease 

Complications

Complications of osteomyelitis may include:^1,5

• Bone death – An infection in the blood can cut off blood flow to the bone which can lead to bone death (osteonecrosis). These parts of the bone will need to be surgically removed and may even warrant an amputation
• Abscesses – An infection in the bone can spread to muscles and soft tissue causing a build-up of pus which can seep through your skin. This is more common in people who suffer from chronic osteomyelitis
• Stunted growth – Osteomyelitis in a growing child may affect the normal growth in their bones or joints. This occurs if the infection is in the softer areas, known as the growth plates, which are found at either end of the long bones of the arms and legs
• Skin cancer – An open sore that is draining pus can lead to skin cancer
• Septic arthritis– A bone infection may spread into a nearby joint and cause arthritis

FAQs

How can I prevent osteomyelitis?

If you have an increased risk of developing osteomyelitis, you should talk to your GP and find ways to reduce your risk of infection. In general, you should:

• Clean and treat wounds to prevent infections
• Be aware of any first signs of infection if you have recently had bone surgery or have an artificial joint
• Avoid minor injuries that can lead to infections e.g. cuts, scraps, bites and animal scratches

How common is osteomyelitis?

Osteomyelitis affects about 10 to 100 out of every 100,000 people.

When should I see a doctor?

You should see a GP if:

• You have signs of infection e.g. fever, bone pain, swelling or redness of the affected area
• You are experiencing pain that makes movement difficult
• You have back pain that is not improving with rest or painkillers
• You have an existing medical condition or have had a recent surgery or injury that makes you prone to infection

Summary

In summary, osteomyelitis is an infectious disease of the bone that causes pain, swelling and damage to the bone that can lead to bone destruction. The three types of osteomyelitis are acute osteomyelitis, chronic osteomyelitis and vertebral osteomyelitis. Osteomyelitis symptoms include fever, tenderness and swelling around the affected area, limited movement and nausea. If you suspect you have osteomyelitis, your GP will examine the affected area and order tests, including blood tests, imaging tests or a bone biopsy. Treatment includes antibiotics or surgery to remove damaged portions of the bone. If left untreated, osteomyelitis can lead to serious complications such as bone death, abscesses, stunted growth and even skin cancer.