What is Septic Arthritis?

Septic arthritis is a bacterial infection in a joint. In children, common joints include the hip, knee, ankle and shoulder.  It can be caused by bacteria entering the blood stream and traveling to the affected joint.  This can occur quite commonly in healthy children. Many times we cannot determine the source of the bacteria.  Infection that occurs in the bone (osteomyelitis) near a joint can sometimes spread to the joint.  When an infection occurs within the joint, an accumulation of pus occurs.  This can occur in neonates, young children, adolescents and adults.

What are signs of Septic Arthritis?  

These signs may include some of the following: rapid onset of painful joint motion, inability to bear weight on the affected joint, fever greater than 38 degrees, generalized unwellness, and a hot, swollen joint.  Physicians use history, clinical exam, blood tests, and sometimes the help of various imaging modalities to make the diagnosis.  There are other diagnoses (like transient synovitis and inflammatory arthritis) that can sometimes mimick septic arthritis and it is important to differentiate these other conditions. 

What is the treatment of Septic Arthritis?

Treatment includes drainage of pus from the affected joint under anesthetic, antibiotic therapy, splinting, and careful orthopedic follow-up.  In complex cases, particularly those associated with a severe and persistent infection in the bone, growth disturbances and other complications can occur.  

American Academy of Orthopedic Surgeons - Bone and Joint Infections in Children