According to the American Academy of Orthopaedic Surgeons, joint, bone and muscle infections in children are often caused by a bacteria called Staphylococcus aureus; these infections are more commonly known as Staph infections. Methicillin-resistant Staphylococcus aureus (MRSA) is another bacterium that causes Staph infection in children.

Bacteria can enter the body in a variety of ways. When it does, bacteria circulate through the bloodstream until reaching a joint, bone or muscle and then multiply in the tissue. Also called deep infections, the types of bacteria-caused infections in children are:

• Osteomyelitis: Bone infection
• Septic arthritis: Joint infection
• Pyomyositis: Muscle infection
• Abscess: An isolated pocket of infection with pus, typically in soft tissues

What are the symptoms of joint, bone or muscle infections in a child?

Deep infections in children are often accompanied by the following symptoms:

• Fever
• Limited movement of a particular area (the area where the infection is)
• Pain
• Redness or warmth of skin in the affected area

Babies with a joint, bone or muscle infection may also:

• Be irritable and unusually tired
• Refuse to eat
• Vomit

In many cases, the deep infection occurs after a recent injury, so symptoms of the infection may be attributed to the injury instead of the infection. Be aware of the symptoms of infection and bring your child to their pediatrician/primary care provider (PCP) immediately, especially if symptoms are not improving or are worsening.

How are deep infections in children diagnosed?

Your child’s PCP will ask you about your child’s medical history and symptoms and will examine the area where your child is experiencing pain. In addition, your child’s PCP may order tests, such as:

• Imaging: X-rays, magnetic resonance imaging (MRI) or an ultrasound to get pictures of the joints, bones, muscles and soft tissue that is infected
• Blood tests and tissue cultures: Help identify the bacteria causing the infection
• Aspiration: Drawing fluid out of the joint or pocket of the infection

What is the treatment for a deep infection in a child?

Early diagnosis and treatment with antibiotics are critical to decreasing the impact of the joint, bone or muscle infection on your child. In mild infections, antibiotics used over a three to six week period may resolve the infection. The types of antibiotics used include:

• Intravenous (IV): At first, your child will need to stay in the hospital to receive IV antibiotics to treat their deep infection; the hospital stay is generally about one week, depending on the how severe the infection is.
• Oral: Once your child is home, a prescription oral antibiotic will be used to continue to fight the infection. The specific antibiotic will be determined by what type of bacteria caused the infection. For example, MRSA is more resistant to common antibiotics, but several antibiotics work well fighting these bacteria.
• PICC line: If oral antibiotics are not able to control the infection at home, IV antibiotics are needed. A PICC line is a special IV line developed for use at home instead of having to bring your child back to the hospital.

More serious infections may require irrigation and debridement, a surgical procedure to remove infected material (pus). In most cases, one such procedure is needed; however, in more severe cases, irrigation and debridement may need to be performed twice. If this surgery is needed, an orthopedic surgeon will perform the procedure.

What are the long term health effects of joint, bone and muscle infections in a child?

Most children will recover completely from a deep infection and will not be likely to develop the same infection again. The earlier the diagnosis and treatment, the greater the chance for a full recovery and return to normal activities.

If a child has a serious or prolonged infection, the following can occur:

• Blood clots: Generally rare in children, have been seen in children with MRSA infections
• Growth arrest: Causes bone to grow abnormally; deformity can occur if the growth plate is injured
• Fractures: May occur in bone weakened from the infection
• Avascular necrosis: Also called bone death, rare but may occur